Latent recycling potential of multilayer films in Austrian waste management

This work presents a hand sorting trial of Austrian plastic packaging, which showed that according to an extrapolation of the 170,000 t separately collected waste collected in Austria, 30 wt% are flexible 2D plastic packaging. Further, the applications for these materials have been catalogued. The composition of these films was evaluated via Fourier-Transformed Infrared Spectroscopy, which showed that 31% of all films were made of polyethene, 39% of polypropylene, 11% of polyethene–polyethene terephthalate composite, and 8% of a polyethene–polypropylene composite, further resulting in the calculation that of all flexible packaging, 20 wt% are multilayer films. These findings were used to calculate the latent potential for raising the current recycling quota of 25.7% to the mandated rate of 55% in 2030. To this end, scenarios depicting different approaches to sorting and recycling small films were evaluated. It was calculated that through improving the sorting of films the recycling rate could be increased to 35.5%. This approach allows for the recycling of monolayer films by avoiding contamination with foreign materials introduced by multilayer films that impede the recyclates’ mechanical properties. The evaluation showed that sorting multilayer films of this fraction could raise the recycling quota further to 38.9%

Temporal contrast sensitivity: A potential parameter for glaucoma progression, especially in advanced stages

INTRODUCTION. Previously it could be shown that temporal contrast sensitivity is affected by glaucoma and maximally influenced after 25-Hz adaptation in normals. This study investigated different kinds of 25-Hz temporal contrast adaptation on TCS in patients with ocular hypertension, preperimetric primary open-angle glaucoma, and perimetric open-angle glaucoma. Additionally, correlations of measured data with parameters of glaucoma diagnostic were done and assessed for the potential use of TCS as a parameter for glaucoma progression. MATERIALS AND METHODS. One hundred and four subjects were included: 44 normals, 14 ocular hypertensions, 11 preperimetric primary open-angle glaucomas, and 35 perimetric open-angle glaucomas. Using the Erlangen Flicker Test, temporal contrast sensitivity was measured without adaptation, after pre-adaptation and after pre- and re-adaptations at 25 Hz. Reliability analyses were done. RESULTS. All test strategies showed high reliability (a-Cronbach’s > 0.86). In normals, age-dependency of temporal contrast sensitivity without adaptation (p = 0.052) and after pre- and re-adaptation (p = 0.008) was observed. Temporal contrast sensitivity is significantly reduced after pre-adaptation for all subjects (p < 0.001). Reduction of temporal contrast sensitivity after pre- and re-adaptations was significant in all groups (p < 0.001), but it was smaller than after single pre-adaptation (p < 0.001). Temporal contrast sensitivity without adaptation was significantly reduced in patients with perimetric glaucoma (p = 0.040) but not in patients with ocular hypertension and preperimetric glaucoma. Correlation analyses yielded a significant correlation between temporal contrast sensitivity without adaptation and mean defect (p = 0.003, r = –0.329), loss variance (p = 0.027, r = –0.256), and retinal nerve fibre layer thickness (p < 0.001, r = 0.413) for all subjects and between temporal contrast sensitivity after pre-adaptation and mean defect (p = 0.045, r = –0.239). CONCLUSIONS. Temporal contrast sensitivity seems to be affected in perimetric glaucoma with an overall reduction after adaptation. Significant correlations of temporal contrast sensitivity with perimetric and morphologic parameters offer new aspects of its potential use as a glaucoma progressions marker, especially in advanced stages when perimetric diagnosis is limited

25 Hz adaptation: Influence on recovery time in glaucoma

INTRODUCTION. Normal temporal contrast sensitivity is maximally influenced by pre-adaptation with 25-Hz temporal contrast flicker. The aim of this study was to investigate the effects of 25-Hz contrast adaptation on recovery of contrast sensitivity in normals, patients with ocular hypertension, preperimetric, perimetric and advanced perimetric open-angle glaucoma. MATERIALS AND METHODS. Temporal contrast sensitivity was examined after pre-adaptation with 25 Hz in the following: 43 normals, 14 ocular hypertension, 10 preperimetric primary open-angle glaucoma, and 33 perimetric open-an­gle glaucoma patients. After pre-adaptation (the time after which a test stimulus could be detected again), recovery time (RT) was measured at 3% and 5% test contrast. Additionally, 25 patients with advanced perimetric open-angle glaucoma were measured at 12%, 25%, and 35% contrast and compared to a normal group consisting of 15 subjects. RESULTS. 1. Measurements of RT are reliable (Cronbach’s a > 0.8). 2. RT was age-dependent requiring an age-correction in further analyses. 3. RT3% and RT5% were significantly prolonged in perimetric primary open-angle glau­coma compared to normals (3% test contrast: p = 0.007; 5% test contrast: p = 0.035). 4. Within each group, RT3% and RT5% were significantly different at both test contrasts (normals, perimetric open-angle glaucoma: p < 0.001; ocular hypertension: p = 0.007; preperimetric open-angle glaucoma: p = 0.035). 5. RT3% and RT5% were significantly correlated with mean defect (p < 0.001) and retinal nerve fibre layer thickness (p = 0.018). RT5% was correlated with loss variance (p = 0.048). 6. RT12%, RT25% and RT35% were significantly prolonged in advanced perimetric glaucoma (p < 0.001), and correlated with mean defect (p < 0.001, p = 0.002, p = 0.013) and retinal nerve fibre layer thickness (p < 0.001, p = 0.003, p = 0.013). RT12% was also correlated with loss variance (p = 0.016). CONCLUSIONS. Measurements of RT after 25-Hz pre-adaptation can be used in glaucoma diagnosis and follow-up examination, especially in monitoring glaucoma progress in advanced perimetric primary open-angle glaucoma

Molecular and phylogenetic characterization of honey bee viruses, Nosema microsporidia, protozoan parasites, and parasitic mites in China

China has the largest number of managed honey bee colonies, which produce the highest quantity of honey and royal jelly in the world; however, the presence of honey bee pathogens and parasites has never been rigorously identified in Chinese apiaries. We thus conducted a molecular survey of honey bee RNA viruses, Nosema microsporidia, protozoan parasites, and tracheal mites associated with nonnative Apis mellifera ligustica and native Apis cerana cerana colonies in China. We found the presence of black queen cell virus (BQCV), chronic bee paralysis virus (CBPV), deformed wing virus (DWV), Israeli acute paralysis virus (IAPV), and sacbrood virus (SBV), but not that of acute bee paralysis virus (ABPV) or Kashmir bee virus (KBV). DWV was the most prevalent in the tested samples. Phylogenies of Chinese viral isolates demonstrated that genetically heterogeneous populations of BQCV, CBPV, DWV, and A. cerana-infecting SBV, and relatively homogenous populations of IAPV and A. meliifera-infecting new strain of SBV with single origins, are spread in Chinese apiaries. Similar to previous observations in many countries, Nosema ceranae, but not Nosema apis, was prevalent in the tested samples. Crithidia mellificae, but not Apicystis bombi was found in five samples, including one A. c. cerana colony, demonstrating that C. mellificae is capable of infecting multiple honey bee species. Based on kinetoplast-encoded cytochrome b sequences, the C. mellificae isolate from A. c. cerana represents a novel haplotype with 19 nucleotide differences from the Chinese and Japanese isolates from A. m. ligustica. This suggests that A. c. cerana is the native host for this specific haplotype. The tracheal mite, Acarapis woodi, was detected in one A. m. ligustica colony. Our results demonstrate that honey bee RNA viruses, N. ceranae, C. mellificae, and tracheal mites are present in Chinese apiaries, and some might be originated from native Asian honey bees

A new threat to bees? Entomopathogenic nematodes used in biological pest control cause rapid mortality in Bombus terrestris

There is currently a great deal of concern about population declines in pollinating insects. Many potential threats have been identified which may adversely affect the behaviour and health of both honey bees and bumble bees: these include pesticide exposure, and parasites and pathogens. Whether biological pest control agents adversely affect bees has been much less well studied: it is generally assumed that biological agents are safer for wildlife than chemical pesticides. The aim of this study was to test whether entomopathogenic nematodes sold as biological pest control products could potentially have adverse effects on the bumble bee Bombus terrestris. One product was a broad spectrum pest control agent containing both Heterorhabditis sp. and Steinernema sp., the other product was specifically for weevil control and contained only Steinernema kraussei. Both nematode products caused ≥80% mortality within the 96 h test period when bees were exposed to soil containing entomopathogenic nematodes at the recommended field concentration of 50 nematodes per cm soil. Of particular concern is the fact that nematodes fromthe broad spectrum product could proliferate in the carcasses of dead bees, and therefore potentially infect a whole bee colony or spread to the wider environment

Age-related pharmacodynamics in a bumblebee-microsporidian system mirror similar patterns in vertebrates

Immune systems provide a key defence against diseases. However, they are not a panacea and so both vertebrates and invertebrates co-opt naturally occurring bioactive compounds to treat themselves against parasites and pathogens. In vertebrates this co-option is complex, with pharmacodynamics leading to differential effects of treatment at different life stages, which may reflect age-linked differences in the immune system. However, our understanding of pharmacodynamics in invertebrates is almost non-existent. Critically, this knowledge may elucidate broad parallels across animals in regard to the requirement for the co-option of bioactive compounds to ameliorate disease. Here we use biochanin A, an isoflavone found in the pollen of red clover (Trifolium pratense), to therapeutically treat Nosema bombi (Microsporidia) infection in bumblebee (Bombus terrestris) larvae and adults, and thus examine age-linked pharmacodynamics in an invertebrate. Therapeutic treatment of larvae with biochanin A did not reduce the infection intensity of N. bombi in adults. In contrast, therapeutic treatment of adults did reduce the infection intensity of N. bombi. This transition in parasite resistance to bioactive compounds mirrors the age-linked pharmacodynamics of vertebrates. Understanding how different life-history stages respond to therapeutic compounds will provide novel insights into the evolution of foraging and self-medication behaviour in natural systems more broadly

Bringing Back a Healthy Buzz? Invertebrate Parasites and Reintroductions:A Case Study in Bumblebees

Reintroductions can play a key role in the conservation of endangered species. Parasites may impact reintroductions, both positively and negatively, but few case studies of how to manage parasites during reintroductions exist. Bumblebees are in decline at regional and global scales, and reintroductions can be used to re-establish extinct local populations. Here we report on how the risks associated with parasites are being managed in an ongoing reintroduction of the short-haired bumblebee, Bombus subterraneus, to the UK. Disease risk analysis was conducted and disease risk management plans constructed to design a capture-quarantine-release system that minimised the impacts on both the bumblebees and on their natural parasites. Given that bumblebee parasites are (i) generalists, (ii) geographically ubiquitous, and (iii) show evidence of local adaptation, the disease risk management plan was designed to limit the co-introduction of parasites from the source population in Sweden to the destination site in the UK. Results suggest that this process at best eliminated, or at least severely curtailed the co-introduction of parasites, and ongoing updates of the plan enabled minimization of impacts on natural host-parasite dynamics in the Swedish source population. This study suggests that methods designed for reintroductions of vertebrate species can be successfully applied to invertebrates. Future reintroductions of invertebrates where the parasite fauna is less well known should take advantage of next-generation barcoding and multiple survey years prior to the start of reintroductions, to develop comprehensive disease risk management plans

The impacts of predators and parasites on wild bumblebee colonies

1. The study of wild bumblebee nests has been hindered by the difficulty in locating and observing them. Here, 47 wild nests were located using a sniffer dog and volunteers. The entrances to 32 nests were filmed continuously to identify successful nests (those that produced gynes) and observe vertebrate species interactions.   2. Of the 47 nests, 71% and 21% produced gynes in 2010 and 2011, respectively.  3. A total of 39 vertebrate species were filmed at entrances but the majority did not interact with the nests. Great tits (Parus major) depredated or attempted to depredate bees on 32 occasions at the entrances to 10 nests, something that has not previously been described. Small mammals were very often recorded accessing entrances to bumblebee nests, but whether they depredated bees was not known, and frequently visited nests were no less likely to produce gynes. Eight nests were entered by adult wax moths,Aphomia sociella.  4. The faeces of 1179 workers from 29Bombus terrestrisnests were screened microscopically for parasites.Crithidia bombiinfections were apparent in 49% of worker bees, whileNosema bombiandApicystis bombiwere present in 5.5% and 0.68% of bees, respectively. Nests with a high prevalence ofC. bombiinfection were less likely to produce gynes, the first evidence of a direct impact of this common parasite on bumblebee colony reproduction in wild nests.  5. Overall, our data indicate that bumblebee nests are at the heart of a rich web of interactions between many different predator and parasite species