A study on shape-dependent settling of single particles with equal volume using surface resolved simulations

A detailed knowledge of the influence of a particle’s shape on its settling behavior is useful for the prediction and design of separation processes. Models in the available literature usually fit a given function to experimental data. In this work, a constructive and data-driven approach is presented to obtain new drag correlations. To date, the only considered shape parameters are derivatives of the axis lengths and the sphericity. This does not cover all relevant effects, since the process of settling for arbitrarily shaped particles is highly complex. This work extends the list of considered parameters by, e.g., convexity and roundness and evaluates the relevance of each. The aim is to find models describing the drag coefficient and settling velocity, based on this extended set of shape parameters. The data for the investigations are obtained by surface resolved simulations of superellipsoids, applying the homogenized lattice Boltzmann method. To closely study the influence of shape, the particles considered are equal in volume, and therefore cover a range of Reynolds numbers, limited to [9.64, 22.86]. Logistic and polynomial regressions are performed and the quality of the models is investigated with further statistical methods. In addition to the usually studied relation between drag coefficient and Reynolds number, the dependency of the terminal settling velocity on the shape parameters is also investigated. The found models are, with an adjusted coefficient of determination of 0.96 and 0.86, in good agreement with the data, yielding a mean deviation below 5.5% on the training and test dataset

Ryania Speciosa: an insecticide for organic orchards?

Ryania speciosa is a grove belonging to the family Flacourtiacea, located in tropical climates in Central- and South- America. The Indigenous population used the plant, which contains toxic alkaloids, against cockroaches. In the forties the ground wood was used as insecticide against different pests. In the first version of annex 2b from the EC regulation 2092/91, Ryania was still listed, but it was subsequently cancelled due to its lack of registration as a pesticide in any European country. In organic farming, only a few insecticides are allowed, but in orchards there is a permanent need to control larvae such as coddling moth, etc. The Italian Ministry of Agriculture initiated a survey to investigate the possibility of developing an 'organic' pesticide based on Ryania. Basic research was done, working on extraction methods, synergists, spectrum of action, degradation, and efficacy in comparison with other modern pesticides including ecotoxicological investigations. Organic fruit growers hope that a company takes on Ryania to pass it through the registration procedure and puts some formulations on the market

Aquatic pollution from anthropogenic discharges modulates gene expression in liver of rainbow trout (Oncorhynchus mykiss)

With the aim to characterise the biological impact of anthropogenic discharge in a river, gene expression in fish was evaluated as a biomarker for mixture effects of potential toxic compounds in the aquatic environment. Adult male rainbow trout (Oncorhynchus mykiss) were used as monitoring organisms. Within the German experimental set up, trout were exposed actively for 28 days in biologically purified sewage as well as in river water up- and downstream of the sewage treatment plant (STP) effluent. In a different approach, wild trout were captured in southern Chile near anthropogenic discharges. Fish were taken from river Maullin receiving sewage from a settlement and from river Pescado influenced by effluents from a fish farm. In vivo effects were assessed by RT-qPCR analyses of biomarker gene expression, vitellogenin (vg), metallothionein (mt) and cytochrome 1A (cyp1A) in liver samples with primers amplifying specific sequences previously confirmed by cloning and sequencing. The modulation of expression of marker genes involved in metal stress, reproduction and detoxifying systems in the liver of male rainbow trout revealed organismal response to anthropogenic contamination in two different study areas, such as Chile and Germany, thereby indicating a potential risk on the aquatic ecosystems

Feather Corticosterone Measurements and Behavioral Observations in the Great White Pelican (Pelecanus onocrotalus) Living under Different Flight Restraint Conditions in German Zoos

The welfare of zoo birds kept under flight restraint is a frequently discussed topic. Therefore, this study was conducted with one of the most regularly kept types of deflighted birds in German zoos, the great white pelican, to find scientific data regarding welfare assessments of deflighted birds. The detection of corticosterone in feathers (CORTf) as a stress indicator for birds is an almost completely noninvasive form of measurement meant to evaluate the effects of deflighting birds in zoos. Three groups of animals were compared: irreversibly deflighted pelicans that were pinioned or extirpated, reversibly deflighted individuals that were feather-clipped, and airworthy pelicans that were able to fly. Combining two independent research methods, behavioral observation and the measurement of CORTf levels of great white pelicans, we aimed to obtain an objective overview of whether deflighted birds showed differences in CORTf or behavior compared to airworthy birds. As a result of the analysis, we found no significant differences in CORTf between flight-restricted and airworthy birds. However, reversibly deflighted pelicans had higher CORTf values than irreversibly deflighted and airworthy pelicans. In addition, pelicans living in groups consisting of more than 10 individuals showed lower CORTf values than pelicans in groups of less than 10 individuals. "Fluttering" behavior was significantly associated with higher CORTf values. In conclusion, the flight restriction of great white pelicans does not seem to impact the welfare indicators assessed in this study, adrenal activity, or behavior. The data show that the living conditions of pelicans (such as group size) may influence the welfare of these birds. To confirm this, further studies on other ground- and water-based birds are needed to provide more scientific data on animal welfare and living conditions in zoos. The pinioning of birds was previously one of the most-accepted forms of mutilation in zoos. Despite a lack of knowledge on the effects of deflighting procedures with regard to the well-being of deflighted birds, pelicans are often reversibly deflighted by feather-clipping to keep them in open enclosures, including those with ponds without netting. In the present study, we focused on the welfare implications of flight restraint on one of the most commonly kept types of birds in German zoos, the great white pelican. A combination of behavioral observations and feather corticosterone concentrations (CORTf) of pelicans with different deflighting statuses (i.e., irreversibly deflighted, reversibly deflighted, and airworthy) was used to evaluate the effects of deflighting status on pelican welfare. We observed 215 individuals in 21 different German zoos. The pelicans lived in differently designed exhibits. An ethogram for these species was developed and their behavior was evaluated by scan sampling. Feather samples from 182 individuals were collected to determine if different deflighting conditions influenced the CORTf and therefore stress levels. The hypothesis was that the CORTf values of airworthy pelicans differ from those of deflighted pelicans. Tendencies with regard to the flight status groups were found. Conversely, reversibly deflighted pelicans had higher CORTf levels than irreversible deflighted and airworthy pelicans. Tendencies with regard to CORTf values and the group size of the kept pelicans were observed. The CORTf values were lower in groups consisting of more than 10 animals. In addition, the frequency of fluttering behavior was positively associated with CORTf values. Pelicans that frequently showed fluttering had higher CORTf values. Therefore, fluttering behavior might be considered a sign of stress levels in pelicans. This study is one of the first important steps in assessing the impact of deflighting procedures on the welfare of great white pelicans kept in zoos

Feather corticosterone measurements of greater flamingos living under different forms of flight restraint

This research was supported by the German Association of Zoological Gardens (Verband der Zoologischen Gärten e.V, VdZ) with 20,000 €.Deflighting zoo birds is a practice that receives increasing criticism due to its presumed incompatibility with animal welfare. To our knowledge, this is the first approach to address this problem in a scientific way. To do this, we compared feather corticosterone (CORTf) from Greater Flamingos (Phoenicopterus roseus, n = 151) of different flight status (i.e., pinioned, feather clipped, airworthy) from twelve different zoological institutions. To complement the hormone measurements, behavioral observations (scan samplings) were conducted prior to feather sampling within the presumed time frame of feather growth. We hypothesized that CORTf of the deflighted flamingos would differ from CORTf of their airworthy conspecifics. No significant difference in CORTf was found between the three groups, and our hypothesis was rejected. However, the impact of the institution itself (i.e., the housing conditions) proved to be the most dominant variable (variance between the institutions = 53.82%). Due to high variability, the behavioral observations were evaluated descriptively but did not give rise to doubt the findings in CORTf. Therefore, we assume that the method of flight restraint of Greater Flamingos does not have a measurable effect on CORTf. We consider this model for evaluating animal welfare of zoo birds a useful tool and provide ideas for further adjustments for consecutive studies

Use of Next Generation Sequencing to study two cowpox virus outbreaks

Background Between 2008 and 2011 about 40 cases of human cowpox were reported from Germany and France. Infections had been acquired via close contact to infected, young pet rats. An identical and unique sequence of the hemagglutinin gene was found in various cowpox virus (CPXV) isolates pointing to a common source of infection. In a second CPXV outbreak in cats in a small animal clinic in Germany in 2015, four out of five hospitalized cats showed identical hemagglutinin sequences and thus, a hospital-acquired transmission had been assumed. Next-Generation Sequencing was performed in order to re-investigate the outbreaks, as epidemiological data could not confirm all cases. Methods Homogenates of lesion material from rats, cats and humans were cultivated in cell culture. The genomes of four virus isolates, nine CPXVs from our strain collections and from DNA of three paraffin-embedded lesion materials were determined by Next Generation Sequencing (NGS). For phylogenetic analyses a MAFFT-alignment was generated. A distance matrix based on concatenated SNPs was calculated and plotted as dendrogram using Unweighted Pair Group Method with Arithmetic mean (UPGMA) for visualization. Results Aligning of about 200.000 nucleotides of 8 virus isolates associated with the pet rat outbreak revealed complete identity of six genomes, the remainder two genomes differed in as little as 3 SNPs. When comparing this dataset with four already published CPXV genomes also associated with the pet rat outbreak, again a maximum difference of 3 SNPs was found. The outbreak which lasted from 2008 till 2011 was indeed caused by a single strain which has maintained an extremely high level of clonality over 4 years. Aligning genomic sequences from four cases of feline cowpox revealed 3 identical sequences and one sequence which differed in 65 nucleotides. Although identical hemagglutinin sequences had been obtained from four hospitalized cats, genomic sequencing proved that a hospital-acquired transmission had occurred in only three cats. Conclusion Analyzing the rather short sequence of the hemagglutinin gene is not sufficient to conduct molecular trace back analyses. Instead, whole genome sequencing is the method of choice which can even be applied to paraffin-embedded specimens

Visual assessment of the impact of agricultural management practices on soil quality

The intensification of agricultural practices to increase food and feed outputs is apressing challenge causing deterioration of soil quality and soil functions. Such achallenge demands provision of empirical evidence to provide context-sensitive guid-ance on agricultural management practices (AMPs) that may enhance soil quality.The objectives of this study are to identify the most promising AMPs (and their com-binations) applied by farmers with the most positive effects on soil quality and toevaluate the sensitivity of the soil quality indicators to the applied AMPs. The effectof selected AMPs on soil quality was assessed using a visual soil assessment tool ina total of 138 pairs of plots spread across 14 study site areas in Europe and Chinacovering representative pedo-climatic zones. The inventory and scoring of soil qual-ity were conducted together with landowners. Results show that 104 pairs show apositive effect of AMPs on soil quality. Higher effects of the AMPs were observedin lower fertile soils (i.e., Podzols and Calcisols) as opposed to higher fertile soils(i.e., Luvisols and Fluvisols). For the single use applications, the AMPs with positiveeffects were crop rotation; manuring, composting, and no-tillage; followed by organicagriculture and residue maintenance. Cluster analysis showed that the most promis-ing combinations of AMPs with the most positive effects on soil quality are composedof crop rotation, mulching, and min-till. The agreement between scientific skills andempirical knowledge in the field identified by the farmers confirm our findings andensures their applicability

El benestar de les aus amb vol restringit

El benestar de les aus de zoològic amb el vol restringit ha estat objecte d'un estudi realitzat per investigadors de la UAB i de la Universitat de Freie en pelicans de diversos recintes d'Alemanya. Els científics han avaluat el benestar d'aquestes aus a través de l'estudi del seu comportament i dels nivells de l'hormona de l'estrès corticosterona. Els resultats mostren que la restricció de vol no influeix en els criteris de benestar avaluats, tot i que sí que ho fan les condicions de l'entorn. Per confirmar-los, però, calen més dades científiques sobre l'impacte en el benestar d'altres espècies d'aus.El bienestar de las aves de zoológico con el vuelo restringido ha sido objeto de un estudio realizado por investigadores de la UAB y la Universidad de Freie en pelícanos de diversos recintos de Alemania. Los científicos han evaluado el bienestar de estas aves a través del estudio de su comportamiento y de los niveles de la hormona del estrés corticosterona. Los resultados muestran que la restricción de vuelo no influye en los criterios de bienestar avaluados, aunque sí que lo hacen las condiciones del entorno. Para confirmarlos, no obstante, son necesarios más datos científicos sobre otras especies de aves.The welfare of zoo birds kept under flight restraint has been studied by researchers of the UAB and the University of Freie with great white pelicans from German zoos. The scientists have evaluated the well-being of the animals through the ethological study and the levels of stress hormone corticosterone. The results show that the flight restriction does not influence the assessed welfare criteria, although the environmental conditions do. To confirm this, further studies are needed to provide more scientific data on other bird animals in captivity