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Peer reviewe

Insights into the Electronic Structure of a U(IV) Amido and U(V) Imido Complex

Reaction of the N-heterocylic carbene ligand $^{i}$PrIm (L$^{1}$) and lithium bis(trimethylsilyl)amide (TMSA) as a base with UCl$_{4}$ resulted in U(IV) and U(V) complexes. Uranium\u27s +V oxidation state in (HL$^{1}$)$_{2}$[U(V)(TMSI)Cl$_{5}$] (TMSI=trimethylsilylimido) (2) was confirmed by HERFD-XANES measurements. Solid state characterization by SC-XRD and geometry optimisation of [U(IV)(L$^{1}$)$_{2}$(TMSA)Cl$_{3}$] (1) indicated a silylamido ligand mediated inverse trans influence (ITI). The ITI was examined regarding different metal oxidation states and was compared to transition metal analogues by theoretical calculations

<i>In vivo</i> X-ray elemental imaging of single cell model organisms manipulated by laser-based optical tweezers

We report on a radically new elemental imaging approach for the analysis of biological model organisms and single cells in their natural, in vivo state. The methodology combines optical tweezers (OT) technology for non-contact, laser-based sample manipulation with synchrotron radiation confocal X-ray fluorescence (XRF) microimaging for the first time. The main objective of this work is to establish a new method for in vivo elemental imaging in a two-dimensional (2D) projection mode in free-standing biological microorganisms or single cells, present in their aqueous environment. Using the model organism Scrippsiella trochoidea, a first proof of principle experiment at beamline ID13 of the European Synchrotron Radiation Facility (ESRF) demonstrates the feasibility of the OT XRF methodology, which is applied to study mixture toxicity of Cu-Ni and Cu-Zn as a result of elevated exposure. We expect that the new OT XRF methodology will significantly contribute to the new trend of investigating microorganisms at the cellular level with added in vivo capability

An innovative tailored instructional design for computer programming courses in engineering

Industry 4.0 and 5.0 topics are emerging fields and have seen rising demand recently. There is a critical need, on the other hand, for improved methods of instructing programming languages since a growing lack of student motivation during the pandemic has had a deleterious influence on the education of programmers. In this context, online/hybrid computer programming courses must be addressed with innovative solutions to support the field with well-educated professionals. In this paper, we present a case study to propose an innovative tailored instructional design for the online/hybrid learning environments for programming courses in engineering faculties. To develop the instructional design, the Kemp Instructional Design Model was followed. The instructional design is a result of the main outputs of the RECOM “Redesigning Introductory Computer Programming Using Innovative Online Modules” project, which aims to bridge the gap between the existing course design in programming courses and the needs of "Covid” and “post-Covid” generation students

The Globodera pallida SPRYSEC effector GpSPRY-414-2 that suppresses plant defenses targets a regulatory component of the dynamic microtubule network

The James Hutton Institute receives funding from the Scottish Government Rural and Environment Science and Analytical Services division. YM was funded through a BOF Ph.D. scholarship (Bijzonder Onderzoeksfonds, Ghent University). This collaboration was supported by an International Exchanges Award (IE110776) from the Royal Society and benefited from interactions funded by COST Action FA1208.The white potato cyst nematode, Globodera pallida, is an obligate biotrophic pathogen of a limited number of Solanaceous plants. Like other plant pathogens, G. pallida deploys effectors into its host that manipulate the plant to the benefit of the nematode. Genome analysis has led to the identification of large numbers of candidate effectors from this nematode, including the cyst nematode-specific SPRYSEC proteins. These are a secreted subset of a hugely expanded gene family encoding SPRY domain-containing proteins, many of which remain to be characterized. We investigated the function of one of these SPRYSEC effector candidates, GpSPRY-414-2. Expression of the gene encoding GpSPRY-414-2 is restricted to the dorsal pharyngeal gland cell and reducing its expression in G. pallida infective second stage juveniles using RNA interference causes a reduction in parasitic success on potato. Transient expression assays in Nicotiana benthamiana indicated that GpSPRY-414-2 disrupts plant defenses. It specifically suppresses effector-triggered immunity (ETI) induced by co-expression of the Gpa2 resistance gene and its cognate avirulence factor RBP-1. It also causes a reduction in the production of reactive oxygen species triggered by exposure of plants to the bacterial flagellin epitope flg22. Yeast two-hybrid screening identified a potato cytoplasmic linker protein (CLIP)-associated protein (StCLASP) as a host target of GpSPRY-414-2. The two proteins co-localize in planta at the microtubules. CLASPs are members of a conserved class of microtubule-associated proteins that contribute to microtubule stability and growth. However, disruption of the microtubule network does not prevent suppression of ETI by GpSPRY-414-2 nor the interaction of the effector with its host target. Besides, GpSPRY-414-2 stabilizes its target while effector dimerization and the formation of high molecular weight protein complexes including GpSPRY-414-2 are prompted in the presence of the StCLASP. These data indicate that the nematode effector GpSPRY-414-2 targets the microtubules to facilitate infection.Publisher PDFPeer reviewe

TRY plant trait database - enhanced coverage and open access

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives

High Speed and High Efficiency Travelling Wave Single-Photon Detectors Embedded in Nanophotonic Circuits

Ultrafast, high quantum efficiency single photon detectors are among the most sought-after elements in modern quantum optics and quantum communication. High photon detection efficiency is essential for scalable measurement-based quantum computation, quantum key distribution, and loophole-free Bell experiments. However, imperfect modal matching and finite photon absorption rates have usually limited the maximum attainable detection efficiency of single photon detectors. Here we demonstrate a superconducting nanowire detector atop nanophotonic waveguides which allows us to drastically increase the absorption length for incoming photons. When operating the detectors close to the critical current we achieve high on-chip single photon detection efficiency up to 91% at telecom wavelengths, with uncertainty dictated by the variation of the waveguide photon flux. We also observe remarkably low dark count rates without significant compromise of detection efficiency. Furthermore, our detectors are fully embedded in a scalable silicon photonic circuit and provide ultrashort timing jitter of 18ps. Exploiting this high temporal resolution we demonstrate ballistic photon transport in silicon ring resonators. The direct implementation of such a detector with high quantum efficiency, high detection speed and low jitter time on chip overcomes a major barrier in integrated quantum photonics

Low N2_{2}O and variable CH4_{4} fluxes from tropical forest soils of the Congo Basin

Globally, tropical forests are assumed to be an important source of atmospheric nitrous oxide (N$_{2}$O) and sink for methane (CH$_{4}$). Yet, although the Congo Basin comprises the second largest tropical forest and is considered the most pristine large basin left on Earth, in situ N$_{2}$O and CH$_{4}$ flux measurements are scarce. Here, we provide multi-year data derived from on-ground soil flux (n = 1558) and riverine dissolved gas concentration (n = 332) measurements spanning montane, swamp, and lowland forests. Each forest type core monitoring site was sampled at least for one hydrological year between 2016 - 2020 at a frequency of 7-14 days. We estimate a terrestrial CH$_{4}$ uptake (in kg CH$_{4}$-C ha$^{-1}$ yr$^{-1}$) for montane (−4.28) and lowland forests (−3.52) and a massive CH$_{4}$ release from swamp forests (non-inundated 2.68; inundated 341). All investigated forest types were a N$_{2}$O source (except for inundated swamp forest) with 0.93, 1.56, 3.5, and −0.19 kg N$_{2}$O-N ha$^{-1}$ yr$^{-1}$ for montane, lowland, non-inundated swamp, and inundated swamp forests, respectively