Showing papers by "University of Hohenheim published in 2022"

Reduced tillage in organic farming affects soil organic carbon stocks in temperate Europe

Abstract: For decades, conservation tillage has been promoted as a measure to increase carbon stocks in arable soils. Since organic farming improves soil quality and soil carbon storage, reduced tillage under organic farming conditions may further enhance this potential. Therefore, we assessed soil organic carbon (SOC) stocks of reduced tillage compared with mouldboard ploughing in nine organic farming field trials in France, Germany, the Netherlands, and Switzerland with the same sampling and analytical protocol. We sampled soil cores until a depth of 100 cm to determine soil carbon stocks that are relevant for climate change mitigation but are often overlooked in tillage studies with shallow sampling depths. The studied field experiments were between 8 and 21 years old and comprised different soil types with clay contents ranging from 10% to 50%. SOC stocks increased with increasing clay-to-silt ratio, precipitation and organic fertiliser input. Across sites, reduced tillage in comparison with ploughing increased SOC stocks in the surface layer (0–10/15 cm) by 20.8% or 3.8 Mg ha−1, depleted SOC stocks in the intermediate soil layers to 50 cm soil depth with a maximum depletion of 6.6% or 1.6 Mg ha−1 in 15/20–30 cm and increased SOC stocks in the deepest (70–100 cm) soil layer by 14.4% or 2.5 Mg ha−1. The subsoil SOC stock increase may be linked to the inherent soil heterogeneity. Cumulative SOC stocks increased by 1.7% or 1.5 Mg ha−1 (0–50 cm, n = 9) and 3.6% or 4.0 Mg ha−1 (0–100 cm, n = 7) by reduced tillage compared with ploughing with estimated mean C sequestration rates of 0.09 and 0.27 Mg ha−1 yr−1, respectively. There was no effect of field trial duration on tillage induced cumulative SOC stocks differences. Under reduced tillage, biomass production was 8% lower resulting in a decrease of crop C input by 6%. However, this reduction may have been outbalanced by increased C inputs from weed biomass resulting from a higher weed incidence in reduced tillage, which warrants further research. Thus, reduced tillage in organic farming has the potential to increase total SOC stocks, while crop management has to be improved to increase productivity.

COV-ADSX: An Automated Detection System using X-ray Images, Deep Learning, and XGBoost for COVID-19

Abstract: Following the COVID-19 pandemic, scientists have been looking for different ways to diagnose COVID-19, and these efforts have led to a variety of solutions. One of the common methods of detecting infected people is chest radiography. In this paper, an Automated Detection System using X-ray images (COV-ADSX) is proposed, which employs a deep neural network and XGBoost to detect COVID-19. COV-ADSX was implemented using the Django web framework, which allows the user to upload an X-ray image and view the results of the COVID-19 detection and image's heatmap, which helps the expert to evaluate the chest area more accurately.

Dry fractionation of lentils by air classification - Composition, interfacial properties and behavior in concentrated O/W emulsions

Abstract: Dry fractionation has shown to be a promising method to obtain less refined protein ingredients from legumes with novel technofunctionalities compared to solvent extracted protein isolates. However, the relationship between composition and functionality of such fractions especially for use as emulsifiers in concentrated emulsions is still unclear. In this study, investigations were carried out with a variety of lentil fractions having different protein contents, on their ability to emulsify and stabilize concentrated oil-in-water emulsions. Fractions produced by dry fractionation had protein, starch, and fiber contents of 11–54%, 0–58% and 19–32%, respectively, and median particle sizes of samples varied between 6 and 78 μm. Protein solubility and zeta potential varied little, and concentrated oil-in-water emulsions prepared with these different fractions at similar protein contents had similar oil droplet sizes. In contrast, the bulk rheology differed markedly with emulsions exhibiting a more solid like behavior when formed with less-refined fractions. Similarly, differences in the development of interfacial rheology were found. These effects were attributed to differences in the amount and size of non-protein particles, which are entrapped in the droplet network and interact with the interfacial layer, highlighting the importance of the presence of such compounds.

Dry fractionation of lentils by air classification - Composition, interfacial properties and behavior in concentrated O/W emulsions

Abstract: Dry fractionation has shown to be a promising method to obtain less refined protein ingredients from legumes with novel technofunctionalities compared to solvent extracted protein isolates. However, the relationship between composition and functionality of such fractions especially for use as emulsifiers in concentrated emulsions is still unclear. In this study, investigations were carried out with a variety of lentil fractions having different protein contents, on their ability to emulsify and stabilize concentrated oil-in-water emulsions. Fractions produced by dry fractionation had protein, starch, and fiber contents of 11–54%, 0–58% and 19–32%, respectively, and median particle sizes of samples varied between 6 and 78 μm. Protein solubility and zeta potential varied little, and concentrated oil-in-water emulsions prepared with these different fractions at similar protein contents had similar oil droplet sizes. In contrast, the bulk rheology differed markedly with emulsions exhibiting a more solid like behavior when formed with less-refined fractions. Similarly, differences in the development of interfacial rheology were found. These effects were attributed to differences in the amount and size of non-protein particles, which are entrapped in the droplet network and interact with the interfacial layer, highlighting the importance of the presence of such compounds.

Bioavailability and Cardiometabolic Effects of Xanthohumol: Evidence from Animal and Human Studies

Abstract: Xanthohumol is the main prenylflavonoid in hops and has been associated with a wide range of health benefits, due to its anti-inflammatory, anti-oxidative, and cancer-preventive properties. Increasing evidence suggests that xanthohumol positively affects biomarkers associated with metabolic syndrome and cardiovascular diseases (CVDs). This review summarizes the effects of xanthohumol supplementation on body weight, lipid and glucose metabolism, systemic inflammation, and redox status. In addition, it provides insights into the pharmacokinetics of xanthohumol intake. Animal studies show that xanthohumol exerts beneficial effects on body weight, lipid profile, glucose metabolism, and other biochemical parameters associated with metabolic syndrome and CVDs. Although in vitro studies are increasingly elucidating the responsible mechanisms, the overall in vivo results are currently inconsistent and quantitatively insufficient. Pharmacokinetic and safety studies confirm that intake of xanthohumol is safe and well tolerated in both animals and humans. However, little is known about the metabolism of xanthohumol in the human body, and even less about its effects on body weight and CVD risk factors. There is an urgent need for studies investigating whether the effects of xanthohumol on body weight and cardiometabolic parameters observe in animal studies are reproducible in humans, and what dosage, formulation, and intervention period are required.

Almost Equal: Consumption under Fragmented Stigma

Abstract: Abstract How do historically stigmatized social groups consume strategically when they have achieved greater recognition, status, and respectability in society? Based on a seven-year interpretive social representations analysis of gay men in Germany, the authors first show that dominant, stigmatizing representations of such groups do not ameliorate uniformly and for all. Instead, they fragment into oppressive, enabling, and normalized societal representations that different consumers encounter to different degrees in their everyday lives. In the wake of these societal shifts, the stigmatized group itself disintegrates into five representational subgroups, referred to as underground, discrete, hybrid, assimilated, and post-stigma social groups. These subgroups use consumption for different and partly opposing strategic purposes, such as hiding and denial, collective resistance, and deconstruction of differences. The authors synthesize their findings into a conceptual model of consumption under fragmented stigma that extends prior research on consumption under dominant and total stigma configurations and suggests ways in which consumption can not only mitigate but also reinforce stigma. In doing so, they also shed light on the complex lived experiences of a vulnerable social group that has become almost equal.

A transdisciplinary review and framework of consumer interactions with embodied social robots: Design, delegate, and deploy

Abstract: Social robots are gradually entering the organizational frontline, and research is beginning to unveil the implications for consumer–firm interactions. While empirical studies on human–robot service interaction (HRSI) are scarce in business literature, other scientific fields have generated an abundance of empirical findings that can inform consumer research on successfully integrating embodied social robots in consumer-facing services. In this light, a systematic literature review was conducted across scientific fields, screening over 13,500 research articles. Through a thorough review process, 199 service-relevant empirical research articles were identified. Emanating from these data, an organizing meta-framework is advanced (D3: design, delegate, and deploy). Leveraging this D3 framework, a comprehensive overview of several dimensions of the literature is provided, and key insights for each framework dimension are presented. Based on this overview, implications for whether, how, and when to integrate social robots in practice and a comprehensive future research agenda are developed.

Precision Chemical Weed Management Strategies: A Review and a Design of a New CNN-Based Modular Spot Sprayer

Abstract: Site-specific weed control offers a great potential for herbicide savings in agricultural crops without causing yield losses and additional weed management costs in the following years. Therefore, precision weed management is an efficient tool to meet the EU targets for pesticide reduction. This review summarizes different commercial technologies and prototypes for precision patch spraying and spot spraying. All the presented technologies have in common that they consist of three essential parts. (1) Sensors and classifiers for weed/crop detection, (2) Decision algorithms to decide whether weed control is needed and to determine a suitable type and rate of herbicide. Usually, decision algorithms are installed on a controller and (3) a precise sprayer with boom section control or single nozzle control. One point that differs between some of the techniques is the way the decision algorithms classify. They are based on different approaches. Green vegetation can be differentiated from soil and crop residues based on spectral information in the visible and near-infrared wavebands (“Green on Brown”). Those sensors can be applied for real-time on/off control of single nozzles to control weeds before sowing after conservation tillage and in the inter-row area of crops. More sophisticated imaging algorithms are used to classify weeds in crops (“Green on Green”). This paper will focus on Convolutional Neural Networks (CNN) for plant species identification. Alternatively, the position of each crop can be recorded during sowing/planting and afterward herbicides can be targeted to single weeds or larger patches of weeds if the economic weed threshold is exceeded. With a standardized protocol of data communication between sensor, controller and sprayer, the user can combine different sensors with different sprayers. In this review, an ISOBUS communication protocol is presented for a spot sprayer. Precision chemical weed control can be realized with tractor-mounted sprayers and autonomous robots. Commercial systems for both classes will be introduced and their economic and environmental benefits and limitations will be highlighted. Farmers ask for robust systems with less need for maintenance and flexible application in different crops.