Leibniz Universität Hannover

Food Traceability 4.0 refers to the application of fourth industrial revolution (or Industry 4.0) technologies to ensure food authenticity, safety, and high food quality. Growing interest in food traceability has led to the development of a wide range of chemical, biomolecular, isotopic, chromatographic, and spectroscopic methods with varied performance and success rates. This review will give an update on the application of Traceability 4.0 in the fruits and vegetables sector, focusing on relevant Industry 4.0 enablers, especially artificial intelligence, the Internet of Things, blockchain, and big data. The results show that the Traceability 4.0 has significant potential to improve quality and safety of many fruits and vegetables, enhance transparency, reduce the costs of food recalls, and decrease waste and loss. However, due to their high implementation costs and lack of adaptability to industrial environments, most of these advanced technologies have not yet gone beyond the laboratory scale. Therefore, further future research is anticipated to overcome current limitations for large-scale applications.

The generation of two-frequency compound states is very challenging because it requires the access to two incommensurable frequencies that can be group-velocity matched within the considered system. We present here the theoretical investigation of a fiber-based self-generation scheme with a single-color pump as initial condition enabled by soliton fission and the spectral tunneling process. The Raman effect is found to enhance the efficiency of the creation process and the impact of the input pulse parameters on the scheme is investigated.

Models of parallel processing systems typically assume that one has $l$ workers and jobs are split into an equal number of $k=l$ tasks. Splitting jobs into $k \gt l$ smaller tasks, i.e. using “tiny tasks”, can yield performance and stability improvements because it reduces the variance in the amount of work assigned to each worker, but as $k$ increases, the overhead involved in scheduling and managing the tasks begins to overtake the performance benefit. We perform extensive experiments on the effects of task granularity on an Apache Spark cluster, and based on these, develop a four-parameter model for task and job overhead that, in simulation, produces sojourn time distributions that match those of the real system. We also present analytical results which illustrate how using tiny tasks improves the stability region of split-merge systems, and analytical bounds on the sojourn and waiting time distributions of both split-merge and single-queue fork-join systems with tiny tasks. Finally we combine the overhead model with the analytical models to produce an analytical approximation to the sojourn and waiting time distributions of systems with tiny tasks which include overhead. We also perform analogous tiny-tasks experiments on a hybrid multi-processor shared memory system based on MPI and OpenMP which has no load-balancing between nodes. Though no longer strict analytical bounds, our analytical approximations with overhead match both the Spark and MPI/OpenMP experimental results very well.

The virtual element method has been developed over the last decade and applied to problems in solid mechanics. Different formulations have been used regarding the order of ansatz, stabilization of the method and applied to a wide range of problems including elastic and inelastic materials and fracturing processes. This paper is concerned with formulations of virtual elements for higher gradient elastic theories of solids using the possibility, inherent in virtual element methods, of formulating C1-continuous ansatz functions in a simple and efficient way.

Beet necrotic yellow vein virus (BNYVV) causes rhizomania disease in sugar beet (Beta vulgaris), which is controlled since more than two decades by cultivars harboring the Rz1 resistance gene. The development of resistance-breaking strains has been favored by a high selection pressure on the soil-borne virus population. Resistance-breaking is associated with mutations at amino acid positions 67-70 (tetrad) in the RNA3 encoded pathogenicity factor P25 and the presence of an additional RNA component (RNA5). However, natural BNYVV populations are highly diverse making investigations on the resistance-breaking mechanism rather difficult. Therefore, we applied a reverse genetic system for BNYVV (A type) to study Rz1 resistance-breaking by direct agroinoculation of sugar beet seedlings. The bioassay allowed a clear discrimination between susceptible and Rz1 resistant plants already four weeks after infection, and resistance-breaking was independent of the sugar beet Rz1 genotype. A comprehensive screen of natural tetrads for resistance-breaking revealed several new mutations allowing BNYVV to overcome Rz1. The supplementation of an additional RNA5 encoding the pathogenicity factor P26 allowed virus accumulation in the Rz1 genotype independent of the P25 tetrad. This suggests the presence of two distinct resistance-breaking mechanisms allowing BNYVV to overcome Rz1. Finally, we showed that the resistance-breaking effect of the tetrad and the RNA5 is specific to Rz1 and has no effect on the stability of the second resistance gene Rz2. Consequently, double resistant cultivars (Rz1+Rz2) should provide effective control of Rz1 resistance-breaking strains. Our study highlights the flexibility of the viral genome allowing BNYVV to overcome host resistance, which underlines the need for a continuous search for alternative resistance genes.

The contact between bodies is a complex phenomenon that involves mechanical interaction, frictional sliding and heat transfer, among others. A common (and convenient) approach for the mechanical interaction in a finite element framework is to directly use the geometry of the elements to formulate the contact. The main drawback lies in the sharp corners that occur when straight finite elements are connected leading eventually to contact singularities. To circumvent this issue, particularly in the context of beam-to-beam contact, the present work proposes a pointwise contact formulation based on smooth C¹ continuous spline contact elements. The proposed spline-based formulation, which can be directly attached to any quadratic beam finite element formulation, guarantees a smooth description for the whole set of elements, where contact takes place. A specific nonlinear normal contact interaction law and a rheological model for friction, both with elastic and viscous damping contributions, are developed increasing robustness in practical applications. To demonstrate this robustness, specific examples are considered including comparisons with a similar surface-to-surface formulation and an alternative smooth contact scheme, smooth contact with finite elements having sharp corners, modeling of a knot tightening with self-contact, and a simulation involving multiple pointwise contacts.

Antarctic King George Island is the fastest-warming area in the Southern Hemisphere. Organic matter inputs are scarce in this area, as they are derived from lichens, mosses, avian faeces, and minor inputs from two vascular plant species, Deschampsia antarctica É. Desv. and Colobanthus quitensis (Kunth) Bartl. Here, we examined the effects of freezing and thawing (FT) cycles on the priming effect (PE). We hypothesised that soil microorganisms preferentially use freeze-preserved soil organic carbon (SOC) exposed after thawing as an important energy source, resulting in intense PE. Two soils with contrasting clay contents were characterised by attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy and incubated with and without ¹³C-glucose for 21 d. CO2 and ¹³CO2 were recorded from soil (i) without FT, (ii) one FT, and (iii) three FT cycles (− 18/12 °C). SOC exhibited low aromaticity stretching at 920 cm⁻¹ and 1650 cm⁻¹. Glucose-derived CO2 was maximal (26 ± 2.2 mg g⁻¹ C) in the control soil without FT and decreased to 8.6 ± 0.1 mg g⁻¹ C after three cycles. Glucose induced an intensely positive PE, 41–64% of basal respiration for a single FT cycle and 72–76% for no cycles. However, after three FT cycles, there was null or negative PE (− 9.5–0.4%). On average, the SOC content after net C balance increased with freezing frequency from 103 ± 14 to 212 ± 7. mg C kg⁻¹ in low clay forming soil and from 129 ± 14 to 156 ± 2 mg C kg⁻¹ in high clay forming soil and declined with increasing PE in both soils (R² = 0.87, p < 0.01). Diminution in freezing frequency because of global warming will increase the positive PE, affecting the C sequestration of incipient SOC formation in maritime Antarctic soils. Graphic abstract Summary of the results demonstrating the impact of freezing frequency (hypotheses of this study) on the priming effect and the distribution of labeled ¹³C glucose-derived for HCF soil as example. All pools are expressed in mg C kg⁻¹ dry soil

Background In recent years, advances in high-throughput sequencing technologies have enabled the use of genomic information in many fields, such as precision medicine, oncology, and food quality control. The amount of genomic data being generated is growing rapidly and is expected to soon surpass the amount of video data. The majority of sequencing experiments, such as genome-wide association studies, have the goal of identifying variations in the gene sequence to better understand phenotypic variations. We present a novel approach for compressing gene sequence variations with random access capability: the Genomic Variant Codec (GVC). We use techniques such as binarization, joint row- and column-wise sorting of blocks of variations, as well as the image compression standard JBIG for efficient entropy coding. Results Our results show that GVC provides the best trade-off between compression and random access compared to the state of the art: it reduces the genotype information size from 758 GiB down to 890 MiB on the publicly available 1000 Genomes Project (phase 3) data, which is 21% less than the state of the art in random-access capable methods. Conclusions By providing the best results in terms of combined random access and compression, GVC facilitates the efficient storage of large collections of gene sequence variations. In particular, the random access capability of GVC enables seamless remote data access and application integration. The software is open source and available at https://github.com/sXperfect/gvc/.

Ori-kirigami structures offer a good avenue for designing mechanical metamaterials due to their unique advantage of being independent of material properties and scale limitations. Recently, the scientific community has been greatly interested in exploiting the complex energy landscape of ori-kirigami structures to construct multistable systems and play their valuable role in different applications. Here, we present three-dimensional ori-kirigami structures based on generalized waterbomb units, a cylindrical ori-kirigami structure based on waterbomb units, and a conical ori-kirigami structure based on trapezoidal waterbomb units. We investigate the inherent relationships between the unique kinematics and mechanical properties of these three-dimensional ori-kirigami structures and explore their potential usage as mechanical metamaterials that exhibit negative stiffness, snap-through, hysteresis effects, and multistability. What makes the structures even more attractive is their massive folding stroke, where the conical ori-kirigami structure can obtain a huge folding stroke of more than twice its initial height through penetration of its upper and lower boundaries. This study forms the foundation for designing and constructing three-dimensional ori-kirigami metamaterials based on generalized waterbomb units for various engineering applications.

In the age of big data availability, data-driven techniques have been proposed recently to compute the time evolution of spatiotemporal dynamics. Depending on the required a priori knowledge about the underlying processes, a spectrum of black-box end-to-end learning approaches, physics-informed neural networks, and data-informed discrepancy modeling approaches can be identified. In this work, we propose a purely data-driven approach that uses fully convolutional neural networks to learn spatio-temporal dynamics directly from parameterized datasets of linear spatio-temporal processes. The parameterization allows for data fusion of field quantities, domain shapes, and boundary conditions in the proposed Up-Net architecture. Multi-domain Up-Net models, therefore, can generalize to different scenes, initial conditions, domain shapes, and domain sizes without requiring re-training or physical priors. Numerical experiments conducted on a universal and two-dimensional wave equation and the transient heat equation for validation purposes show that the proposed Up-Net outperforms classical U-Net and conventional encoder–decoder architectures of the same complexity. Owing to the scene parameterization, the Up- Net models learn to predict refraction and reflections arising from domain inhomogeneities and boundaries. Generalization properties of the model outside the physical training parameter distributions and for unseen domain shapes are analyzed. The deep learning flow map models are employed for long-term predictions in a recursive time-stepping scheme, indicating the potential for data-driven forecasting tasks. This work is accompanied by an open-sourced code.

The use of the internet is growing rapidly and has become an engine for economic development. However, few studies have examined the impact of internet use on agricultural production, and the results are not yet conclusive. Employing a dataset of more than 2000 observations in rural Vietnam, our study analyses the impact of internet use on agricultural productivity using the heteroscedasticity-based instrument approach suggested by Lewbel, Journal of Business and Economic Statistics, 2012, 30, 67-80 and examines the heterogeneity and distribution of the impact using quantile regressions. Our results show that internet use has significant and positive effects on agricultural productivity. However, these effects are heterogeneous across population groups. The positive effects of internet use are stronger for households with a lower level of education, with a young and female head, and from ethnic minorities. The benefits are also found to be skewed towards the group of farmers at the bottom of the productivity distribution. Therefore, we propose facilitating the diffusion of the internet, since it not only boosts agricultural productivity, but also reduces productivity inequality. In addition, we recommend promoting rural education, supporting local markets, investing more in irrigation systems, and facilitating farm mechanisation as these factors are found to contribute to increasing agricultural productivity.

Materials synthesis via liquid-like mineral precursors has been studied since their discovery almost 25 years ago, because their properties offer several advantages, e.g., the ability to infiltrate small pores, the production of non-equilibrium crystal morphologies or mimicking textures from biominerals, resulting in a vast range of possible applications. However, the potential of liquid-like precursors has never been fully tapped, and they received limited attention in the materials chemistry community, largely due to the lack of efficient and scalable synthesis protocols. Herein, w e present the "scalable controlled synthesis and utilization of liquid-like precursors for technological applications" (SCULPT) method, allowing isolation of the precursor phase on a gram scale, and w e demonstrate its advantage in the synthesis of crystalline calcium carbonate materials and respective applications. The effects of different organic and inorganic additives, such as magnesium ions and concrete superplasticizers, on the stability of the precursor are investigated and allow optimizing the process for specific demands. The presented method is easily scalable and therefore allows synthesizing and utilizing the precursor on large scales. Thus, it can be employed for mineral formation during restoration and conservation applications but can also open up pathways toward calcium carbonate-based, CO2 -neutral cements. This article is protected by copyright. All rights reserved.

Background Most plant-pathogenic Xanthomonas bacteria harbor transcription activator-like effector (TALE) genes, which function as transcriptional activators of host plant genes and support infection. The entire repertoire of up to 29 TALE genes of a Xanthomonas strain is also referred to as TALome. The DNA-binding domain of TALEs is comprised of highly conserved repeats and TALE genes often occur in gene clusters, which precludes the assembly of TALE-carrying Xanthomonas genomes based on standard sequencing approaches. Results Here, we report the successful assembly of the 5 Mbp genomes of five Xanthomonas strains from Oxford Nanopore Technologies (ONT) sequencing data. For one of these strains, Xanthomonas oryzae pv. oryzae (Xoo) PXO35, we illustrate why Illumina short reads and longer PacBio reads are insufficient to fully resolve the genome. While ONT reads are perfectly suited to yield highly contiguous genomes, they suffer from a specific error profile within homopolymers. To still yield complete and correct TALomes from ONT assemblies, we present a computational correction pipeline specifically tailored to TALE genes, which yields at least comparable accuracy as Illumina-based polishing. We further systematically assess the ONT-based pipeline for its multiplexing capacity and find that, combined with computational correction, the complete TALome of Xoo PXO35 could have been reconstructed from less than 20,000 ONT reads. Conclusions Our results indicate that multiplexed ONT sequencing combined with a computational correction of TALE genes constitutes a highly capable tool for characterizing the TALomes of huge collections of Xanthomonas strains in the future.

From the mid-1960s until the late 1980s, the well-known general philosophies of science of the time were applied to economics. The result was disappointing: none seemed to fit. This paper argues that this is due to a special feature of economics: it possesses ‘orientational paradigms’ in high number. Orientational paradigms are similar to Kuhn’s paradigms in that they are shared across scientific communities, but dissimilar to Kuhn’s paradigms in that they are not generally accepted as valid guidelines for further research. As will be shown by several examples, orientational paradigms provide economics with common points of reference that support its epistemic coherence and make scientific discourse more easily possible across school boundaries. With the help of systematicity theory, a newer general philosophy of science, one can further elucidate the role of orientational paradigms with regard to scientific progress.

Multimedia tutorials are more and more considered for online professional training as a valuable complement to traditional in presence training. Indeed, video and pictures can offer rich detail, show relevant context, and provide concrete visualisations of key concepts. An important aspect of achieving effective learning is to create an engaging experience for the learner. This can be obtained by increasing the level of interactivity required to the students, keeping them active and interested. However, there are different categories of interactive video, and what type of interactivity works best for online training needs to be systematically investigated. Moreover, the effort in developing such multimedia tutorials by instructional designers should be sustainable to enable large scale adoption. This calls for the development of appropriate methods and tools to support authors and teachers from the conception of an exercise to its deployment and evolution. These challenges have been addressed in the context of an industrial innovation project called ELEVATE (E-LEarning with Virtual interAcTive Experience). In order to collect empirical evidence on what type of interactive multimedia exercise could be effective in training, we performed an experiment to compare online training exercises based on linear videos with ones based on interactive videos having a graph-structure. Meanwhile, prototypes of the ELEVATE tool suite were being developed and validated in an iterative approach, by adding advanced features, such as those enabling the production of customisable exercises. In this paper, we present the design of the experiment and an execution with sixteen subjects, which provided useful results. The ELEVATE tool suite and the companion methodology are also described, together with the mechanisms it provides to develop customisable multimedia exercises.

The bioavailability of long-chain omega-3 polyunsaturated fatty acids (n3 PUFA) can be affected by the form in which they are bound. An alternative source of n3 PUFA is Calanus finmarchicus oil (CO), which, unlike fish oil (FO) and krill oil (KO), contains fatty acids primarily bound as wax esters. Recent studies have shown that n3 PUFA from CO are bioavailable to humans, but CO has not been compared to other marine oils such as FO or KO. Therefore, the aim of this study was to investigate the influence of 12 weeks supplementation with CO, FO and KO on the long-term n3 PUFA status in healthy volunteers. The Omega-3 Index (O3I), defined as red blood cell EPA + DHA content as a percentage of total identified fatty acids, was used as a measure to assess n3 PUFA status. Sixty-two participants (mean ± standard deviation [SD] age: 29.7 ± 8.43 years) completed the randomized parallel group study (CO group: n = 21, 4 capsules/day, EPA + DHA dose: 242 mg/day; FO group: n = 22, 1 capsule/day, EPA + DHA dose: 248 mg/day; KO group: n = 19, 2 capsules/day, EPA + DHA dose: 286 mg/day). At baseline, the three groups showed comparable (mean ± SD) O3I values (CO: 5.13 ± 1.12%, FO: 4.90 ± 0.57%, KO: 4.87 ± 0.77%). The post-interventional (mean ± SD) O3I increase was comparable between the three groups (CO: 1.09 ± 0.55%; FO: 1.0 ± 0.53%; KO: 1.15 ± 0.65%, all p < 0.001). The study confirms that CO can increase the n3 PUFA status comparable to FO and KO and is therefore an alternative marine source of bioavailable n3 PUFA, especially with regard to sustainability.

Induced interactions and bound states of charge carriers immersed in a quantum medium are crucial for the investigation of quantum transport. Ultracold atom-ion systems can provide a convenient platform for studying this problem. Here, we investigate the static properties of one and two ionic impurities in a bosonic bath using quantum Monte Carlo methods. We identify three bipolaronic regimes depending on the strength of the atom-ion potential and the number of its two-body bound states: a perturbative regime resembling the situation of a pair of neutral impurities, a non-perturbative regime that loses the quasi-particle character of the former, and a many-body bound state regime that can arise only in the presence of a bound state in the two-body potential. We further reveal strong bath-induced interactions between the two ionic polarons. Our findings show that numerical simulations are indispensable for describing highly correlated impurity models.

Studying abroad acts as investment in human capital and ideally outweighs associated investment costs due to higher earnings or related non-monetary benefits. We estimate monetary returns to studying abroad for female graduates 1 and 5 years after graduation. The empirical estimates—based on panel data from four graduate cohorts in 1997, 2001, 2005, and 2009—confirm positive returns to studying abroad. Mobile females earn 3.2% higher wages compared to non-mobiles at labor market entry. These initial wage gains tend to improve further over time, resulting in about 4.0% higher earnings for mobile females 5 years after graduation. Detailed consideration of different socio-economic groups reveals that female graduates from non-academic backgrounds and females majoring in social sciences benefit most. Studying abroad, therefore, has positive effects on later income of female graduates.