The rise of electronic waste (e-waste) generation around the globe has become a major concern in recent times and its recycling is mostly focused on the recovery of valuable metals, such as gold, ...silver, and copper, etc. However, e-waste consists of a significant weight fraction of plastics (25–30%) which are either discarded or incinerated. There is a growing need for recycling of these e-waste plastics. The majority of them are made from high-quality polymers (composites), such as acrylonitrile butadiene styrene (ABS), high impact polystyrene (HIPS), polycarbonate (PC), polyamide (PA), polypropylene (PP) and epoxies. These plastics are often contaminated with hazardous materials, such as brominated flame retardants (BFRs) and heavy metals (such as Pb and Hg). Under any thermal stress (thermal degradation), the Br present in the e-waste plastics produces environmentally hazardous pollutants, such as hydrogen bromide or polybrominated diphenyl ethers/furans (PBDE/Fs). The discarded plastics can lead to the leaching of toxins into the environment. It is important to remove the toxins from the e-waste plastics before recycling. This review article gives a detailed account of e-waste plastics recycling and recovery using thermochemical processes, such as extraction (at elevated temperature), incineration (combustion), hydrolysis, and pyrolysis (catalytic/non catalytic). A basic framework of the existing processes has been established by reviewing the most interesting findings in recent times and the prospects that they open in the field recycling of e-waste plastics.
Display omitted
•Recycling of e-waste plastic is essential for economical disposal of e-waste.•Non-bonded brominated flame retardants can be extracted by organic solvents.•Metal oxide catalysts are suitable for fixation of Br in the pyrolysis.•Hydrothermal treatment can remove both Br and Sb from the e-waste plastics.
We demonstrate a new micro/nanofluidic system for continuous and automatic monitoring of protein product size and quantity directly from the culture supernatant during a high-cell-concentration CHO ...cell perfusion culture. A microfluidic device enables clog-free cell retention for a bench-scale (350 mL) perfusion bioreactor that continuously produces the culture supernatant containing monoclonal antibodies (IgG1). A nanofluidic device directly monitors the protein size and quantity in the culture supernatant. The continuous-flow and fully automated operation of this nanofluidic protein analytics reduces design complexity and offers more detailed information on protein products than offline and batch-mode conventional analytics. Moreover, chemical and mechanical robustness of the nanofluidic device enables continuous monitoring for several days to a week. This continuous and online protein quality monitoring could be deployed at different steps and scales of biomanufacturing to improve product quality and manufacturing efficiency.
Matching with myopic and farsighted players Herings, P. Jean-Jacques; Mauleon, Ana; Vannetelbosch, Vincent
Journal of economic theory,
November 2020, 2020-11-00, Letnik:
190
Journal Article
Recenzirano
Odprti dostop
We introduce the new notion of the pairwise myopic-farsighted stable set to study stable matchings under the assumption that players can be both myopic and farsighted. For the special case where all ...players are myopic, our concept predicts the set of matchings in the core. When all players are farsighted, we provide the characterization of pairwise myopic-farsighted stable sets: a set of matchings is a pairwise myopic-farsighted stable set if and only if it is a singleton consisting of a core element. This result confirms the result obtained by Mauleon et al. (2011) with a completely different effectivity function and provides a new special case where the farsighted stable set is absolutely maximal (Ray and Vohra, 2019) and coincides with the Strong Rational Expectations Farsighted Stable Set (Dutta and Vohra, 2017). When myopic and farsighted players interact, matchings outside the core can be stable and the most farsighted side can achieve its optimal stable matching.
Food webs (i.e., networks of species and their feeding interactions) share multiple structural features across ecosystems. The factors explaining such similarities are still debated, and the role ...played by most organismal traits and their intraspecific variation is unknown. Here, we assess how variation in traits controlling predator–prey interactions (e.g., body size) affects food web structure. We show that larger phenotypic variation increases connectivity among predators and their prey as well as total food intake rate. For predators able to eat only a few species (i.e., specialists), low phenotypic variation maximizes intake rates, while the opposite is true for consumers with broader diets (i.e., generalists). We also show that variation sets predator trophic level by determining interaction strengths with prey at different trophic levels. Merging these results, we make two general predictions about the structure of food webs: (i) trophic level should increase with predator connectivity, and (ii) interaction strengths should decrease with prey trophic level. We confirm these predictions empirically using a global dataset of well-resolved food webs. Our results provide understanding of the processes structuring food webs that include functional traits and their naturally occurring variation.
We introduce the concept of a horizon-K farsighted set to study the influence of the degree of farsightedness on network stability. The concept generalizes existing concepts where all players are ...either fully myopic or fully farsighted. A set of networks Gk is a horizon-K farsighted set if three conditions are satisfied. First, external deviations should be horizon-K deterred. Second, from any network outside of Gk there is a sequence of farsighted improving paths of length smaller than or equal to K leading to some network in GK. Third, there is no proper subset of Gk satisfying the first two conditions. We show that a horizon-K farsighted set always exists and that the horizon-1 farsighted set G₁ is always unique. For generic allocation rules, the set G₁ always contains a horizon-K farsighted set for any K. We provide easy to verify conditions for a set of networks to be a horizon-K farsighted set, and we consider the efficiency of networks in horizon-K farsighted sets. We discuss the effects of players with different horizons in an example of criminal networks.
Summary
Kombucha is a multispecies microbial ecosystem mainly composed of acetic acid bacteria and osmophilic acid‐tolerant yeasts, which is used to produce a probiotic drink. Furthermore, Kombucha ...Mutualistic Community (KMC) has been recently proposed to be used during long space missions as both a living functional fermented product to improve astronauts' health and an efficient source of bacterial nanocellulose. In this study, we compared KMC structure and functions before and after samples were exposed to the space/Mars‐like environment outside the International Space Station in order to investigate the changes related to their re‐adaptation to Earth‐like conditions by shotgun metagenomics, using both diversity and functional analyses of Community Ecology and Complex Networks approach. Our study revealed that the long‐term exposure to space/Mars‐like conditions on low Earth orbit may disorganize the KMC to such extent that it will not restore the initial community structure; however, KMC core microorganisms of the community were maintained. Nonetheless, there were no significant differences in the community functions, meaning that the KMC communities are ecologically resilient. Therefore, despite the extremely harsh conditions, key KMC species revived and provided the community with the genetic background needed to survive long periods of time under extraterrestrial conditions.
We introduce the notion of expectational equilibrium in a general specification of the many-to-one matching with contracts model. The endogenous variables in an expectational equilibrium are ...expectations about tradable contracts. Expectational equilibrium outcomes are equivalent to stable outcomes. Expectational equilibrium unifies all the other approaches used in the literature so far, in particular Walrasian equilibrium, Drèze equilibrium, and market clearing cutoffs. It also applies to cases where contracts do not involve money as well as cases where there is a smallest monetary unit of account.
High-dose chemotherapy plus autologous stem-cell transplantation has been the standard treatment for newly diagnosed multiple myeloma in adults up to 65 years of age. However, promising data on the ...use of combination therapy with lenalidomide, bortezomib, and dexamethasone (RVD) in this population have raised questions about the role and timing of transplantation.
We randomly assigned 700 patients with multiple myeloma to receive induction therapy with three cycles of RVD and then consolidation therapy with either five additional cycles of RVD (350 patients) or high-dose melphalan plus stem-cell transplantation followed by two additional cycles of RVD (350 patients). Patients in both groups received maintenance therapy with lenalidomide for 1 year. The primary end point was progression-free survival.
Median progression-free survival was significantly longer in the group that underwent transplantation than in the group that received RVD alone (50 months vs. 36 months; adjusted hazard ratio for disease progression or death, 0.65; P<0.001). This benefit was observed across all patient subgroups, including those stratified according to International Staging System stage and cytogenetic risk. The percentage of patients with a complete response was higher in the transplantation group than in the RVD-alone group (59% vs. 48%, P=0.03), as was the percentage of patients in whom minimal residual disease was not detected (79% vs. 65%, P<0.001). Overall survival at 4 years did not differ significantly between the transplantation group and the RVD-alone group (81% and 82%, respectively). The rate of grade 3 or 4 neutropenia was significantly higher in the transplantation group than in the RVD-alone group (92% vs. 47%), as were the rates of grade 3 or 4 gastrointestinal disorders (28% vs. 7%) and infections (20% vs. 9%). No significant between-group differences were observed in the rates of treatment-related deaths, second primary cancers, thromboembolic events, and peripheral neuropathy.
Among adults with multiple myeloma, RVD therapy plus transplantation was associated with significantly longer progression-free survival than RVD therapy alone, but overall survival did not differ significantly between the two approaches. (Supported by Celgene and others; IFM 2009 Study ClinicalTrials.gov number, NCT01191060 .).
PDF
