How Much Sorting Is Enough

One strategy for mitigating the effects of rapidly growing global materials consumption is intensified recycling. A key barrier to recycling is the ability to segment or sort constituents within end‐of‐life products. Various sorting technologies hold promise, but each must demonstrate added value to achieve wide‐scale deployment. Potential factors affecting such value include the mix of scrap supply, the nature and mix of finished goods demand, sorting technology performance, and costs. This article examines the use of optimization models to identify economically efficient sorting strategies and their impact on scrap usage. Using this method, this article attempts to identify the conditions that amplify and mute the value of sorting to facilitate recycling. When this method is applied to a case representative of European aluminum secondary production, it is clear that sorting methods can add value in a broad range of conditions. Although better sorting performance (in the form of segmentation efficiency, referred to as recovery rate) correlates positively with cost savings and scrap utilization, it does not always vary monotonically with optimal sorter utilization (i.e., the fraction of scrap sorted rather than unsorted). Furthermore, the case analysis indicates that the value of sorting is more strongly dependent on recovery rate for the more heterogeneous fraction, which, in the case of aluminum, is the cast‐like fraction. Ultimately, sorting increases production flexibility, making a recycler more economically resilient in the face of changing supply and production conditions.     

Removal of ammonia as struvite from anaerobic digester effluents and recycling of magnesium and phosphate

A second order kinetic model was developed to predict the rate and extent of NH(4)(+) removal as struvite from anaerobic digester effluents. Alternative to this, NH(4)(+) can be recovered from struvite and the remaining Mg(2+) and PO(4)(3-) can be recycled back to the wastewater to fix more NH(4)(+). The NH(4)(+) solution was retained and the remaining Mg(2+) and PO(4)(3-) were returned back to be mixed with wastewater. In a five-step process, NH(4)(+) recovery was initially 92% and progressively decreased to 77% in the fifth stage, due to loss of Mg(2+) and PO(4)(3-) at each step in the supernatant. Finally, economic analysis of recycling nutrients was performed and compared to the one step process. The cost of NH(4)(+) recovery was calculated as $0.36/kgNH(4)-N which is lower than $7.7/kgNH(4)-N the cost of one step process without considering the market value of struvite obtained in one step process.     

A small marine biosphere in the Proterozoic

The riverine supply of the globally limiting nutrient, phosphorus, to the ocean accounts for only a few percent of nutrient supply to photosynthetic organisms in surface waters. Recycling of marine organic matter by heterotrophic organisms provides almost all of the phosphorus that drives net primary production in the modern ocean. In the low‐oxygen environments of the Proterozoic, the lack of free oxygen would have limited rates of oxic respiration, slowing the recycling of nutrients and thus limiting global rates of photosynthesis. A series of steady‐state mass balance calculations suggest that the rate of net primary production in the ocean was no more than 10% of its modern value during the Proterozoic eon, and possibly less than 1%. The supply of nutrients in such a world would be dominated by river input, rather than recycling within the water column, leading to a small marine biosphere found primarily within estuarine environments.     

Potentials and limits of mechanical plastic recycling

Plastics consumption continues to steeply increase worldwide, while resultant waste is currently mostly landfilled, discarded to the environment, or incinerated. This significantly contributes to global warming and causes negative health and ecosystem effects. Increasing the circularity of plastics can reduce these impacts. This study investigated to which extent plastics' circularity can be increased by mechanical recycling. For this purpose, future scenarios involving increased waste collection, improved product design, and improved waste sorting were assessed. The system studied consists of 11 plastic types in 69 product groups consumed and arising as waste in Switzerland. By means of a material flow analysis, the amounts of consumption, waste, and secondary material utilizable in product manufacturing were quantified for the year 2040. For the waste not mechanically recycled, treatment situations mainly involving energy recovery in waste-to-energy plants and cement kilns were modeled. A life cycle assessment of the complete plastic material flow system was conducted. We found that the mechanical recycling rate calculated based on the utilizable secondary material can be increased to up to 31%. This can lower the plastic carbon footprint by one quarter (1.3% of today's total Swiss carbon footprint) compared to no recycling. Important barriers to a further increase of the recycling rate were inaccessibility, the large diversity of plastic grades, and contamination. The remaining impact at maximum recycling is mainly caused by polyurethanes, polypropylene, and polystyrene production. In conclusion, the potential of mechanical plastic recycling is limited, but it can, as one of several measures, contribute to combating climate change.     

Adaptive hybrid storage systems leveraging SSDs and HDDs in HPC cloud environments

Cloud computing should inherently support various types of data-intensive workloads with different storage access patterns. This makes a high-performance storage system in the Cloud an important component. Emerging flash device technologies such as solid state drives (SSDs) are a viable choice for building high performance computing (HPC) cloud storage systems to address more fine-grained data access patterns. However, the bit-per-dollar SSD price is still higher than the prices of HDDs. This study proposes an optimized progressive file layout (PFL) method to leverage the advantages of SSDs in a parallel file system such as Lustre so that small file I/O performance can be significantly improved. A PFL can dynamically adjust chunk sizes and stripe patterns according to various I/O traffics. Extensive experimental results show that this approach (i.e. building a hybrid storage system based on a combination of SSDs and HDDs) can actually achieve balanced throughput over mixed I/O workloads consisting of large and small file access patterns.     

On mitigating emissions leakage under biofuel policies

A reason for much pessimism about the environmental benefits of today's biofuels, essentially corn and sugarcane ethanol, is the so‐called indirect land‐use change (ILUC) emissions associated with expanding biofuel production. While there exist several simulation‐based estimates of indirect emissions, the empirical basis underlying key input parameters to such simulations is not beyond doubt, while empirical verification of indirect emissions is hard. Regardless, regulators have adopted global warming intensity ratings for biofuels based on those simulations and in some case are holding regulated firms accountable for (some forms of) leakage. Suffice to say that both the estimates of and the approach to regulating leakage are controversial. The objective of this study is therefore to review a wider economic in order to identify a broader set of policy options for mitigating emissions leakage. We find that controlling leakage by affixing responsibility to regulated firms lacks support in the broader literature, which emphasizes alternative approaches.     

基于生命周期方法的生活垃圾资源化利用系统生态效率分析

我国生活垃圾产量大但处理能力不足,产生多种环境危害,对其资源化利用能够缓解环境压力并回收资源。为探讨生活垃圾资源化利用策略,综合生命周期评价与生命周期成本分析方法,建立生态效率模型。以天津市为例,分析和比较焚烧发电、卫生填埋-填埋气发电、与堆肥+卫生填埋3种典型生活垃圾资源化利用情景的生态效率。结果表明,堆肥+卫生填埋情景具有潜在最优生态效率;全球变暖对总环境影响贡献最大,而投资成本对经济影响贡献最大。考虑天津市生活垃圾管理现状,建议鼓励发展生活垃圾干湿组分分离及厨余垃圾堆肥的资源化利用策略。     

Quantifying Efficiency Loss of Perovskite Solar Cells by a Modified Detailed Balance Model

A modified detailed balance model is built to understand and quantify efficiency loss of perovskite solar cells. The modified model captures the light‐absorption‐dependent short‐circuit current, contact and transport‐layer‐modified carrier transport, as well as recombination and photon‐recycling‐influenced open‐circuit voltage. The theoretical and experimental results show that for experimentally optimized perovskite solar cells with the power conversion efficiency of 19%, optical loss of 25%, nonradiative recombination loss of 35%, and ohmic loss of 35% are the three dominant loss factors for approaching the 31% efficiency limit of perovskite solar cells. It is also found that the optical loss climbs up to 40% for a thin‐active‐layer design. Moreover, a misconfigured transport layer introduces above 15% of energy loss. Finally, the perovskite‐interface‐induced surface recombination, ohmic loss, and current leakage should be further reduced to upgrade device efficiency and eliminate hysteresis effect. This work contributes to fundamental understanding of device physics of perovskite solar cells. The developed model offers a systematic design and analysis tool to photovoltaic science and technology.     

Elaboration of an algae‐to‐energy system and recovery of water and nutrients from municipal sewage

Increasing pressure is being exerted on the peri‐urban space that has elevated the demand for electricity, affects the global water resource, and impacts the potential to produce food, fiber, and commodity products. Algae‐based technologies and in particular algae‐based sewage treatment provides an opportunity for recovery of water for recycle and re‐use, sequestration of greenhouse gases, and generation of biomass. Successful coupling of municipal sewage treatment to an algae‐to‐energy facility depends largely on location, solar irradiance, and temperature to achieve meaningful value recovery. In this paper, an algae‐to‐energy sewage treatment system for implementation in southern Africa is elaborated. Using results from the continued operation of an integrated algal pond system (IAPS), it is shown that this 500‐person equivalent system generates 75 kL per day water for recycle and re‐use and, ～9 kg per day biomass that can be converted to methane with a net energy yield of ～150 MJ per day, and ～0.5 kL per day of high nitrogen‐containing liquid effluent (>1 g/L) with potential for use as organic fertilizer. It is this opportunity that IAPS‐based algae‐to‐energy sewage treatment provides for meaningful energy and co‐product recovery within the peri‐urban space and, which can alleviate pressure on an already strained water–energy–food nexus.     

Global declines in human‐driven mangrove loss

Global mangrove loss has been attributed primarily to human activity. Anthropogenic loss hotspots across Southeast Asia and around the world have characterized the ecosystem as highly threatened, though natural processes such as erosion can also play a significant role in forest vulnerability. However, the extent of human and natural threats has not been fully quantified at the global scale. Here, using a Random Forest‐based analysis of over one million Landsat images, we present the first 30 m resolution global maps of the drivers of mangrove loss from 2000 to 2016, capturing both human‐driven and natural stressors. We estimate that 62% of global losses between 2000 and 2016 resulted from land‐use change, primarily through conversion to aquaculture and agriculture. Up to 80% of these human‐driven losses occurred within six Southeast Asian nations, reflecting the regional emphasis on enhancing aquaculture for export to support economic development. Both anthropogenic and natural losses declined between 2000 and 2016, though slower declines in natural loss caused an increase in their relative contribution to total global loss area. We attribute the decline in anthropogenic losses to the regionally dependent combination of increased emphasis on conservation efforts and a lack of remaining mangroves viable for conversion. While efforts to restore and protect mangroves appear to be effective over decadal timescales, the emergence of natural drivers of loss presents an immediate challenge for coastal adaptation. We anticipate that our results will inform decision‐making within conservation and restoration initiatives by providing a locally relevant understanding of the causes of mangrove loss.     

The number of missing teeth in people of the Edo period in Japan in the 17th to 19th centuries

doi: 10.1111/j.1741‐2358.2011.00511.x The number of missing teeth in people of the Edo period in Japan in the 17th to 19th centuries Objective: The aims of this study were to examine the number of missing teeth in the people of the Edo period (or number of remaining teeth) and to contribute to the 8020 movement proposed in Japan to help people retain 20 or more of their own teeth until the age of 80. Background: The study of dentition in ancient skeletal remains of our ancestors from multiple perspectives can yield information that can contribute to the study of physical anthropology and the leading edge of modern dental research. Materials and methods: The materials were 82 excavated individuals (52 males and 30 females) from 1603 to 1868 whose maxillas and mandibles were both examinable. The age and sex were estimated by anthropological methods, and the individuals were divided into five groups. The status of missing teeth was compared between groups, and a chi‐square test was used to test significant differences between groups. The rates of tooth loss were examined in the maxillas and mandibles. Results: In the people of the Edo period, many teeth remained in good condition until early to late middle age. There were more remaining teeth in these individuals than in modern‐day individuals. However, the Edo people clearly showed increased tooth loss with age. There were no differences in tooth loss by sex. The tooth type with a high rate of tooth loss was posterior teeth, but incisor loss also occurred with ageing. Mandibular canines were most likely to be remaining. Conclusion: The Edo people had more remaining teeth than modern‐day society. This finding was unexpected. The notion that “people of long past ages lost more teeth more quickly” does not seem to apply to people in the Edo period in Japan.     

Bird diversity and endemism along a land‐use gradient in Madagascar: The conservation value of vanilla agroforests

Land‐use change is the most important driver of biodiversity loss worldwide and particularly so in the tropics, where natural habitats are transformed into large‐scale monocultures or heterogeneous landscape mosaics of largely unknown conservation value. Using birds as an indicator taxon, we evaluated the conservation value of a landscape mosaic in northeastern Madagascar, a biodiversity hotspot and the center of global vanilla production. We assessed bird species richness and composition by conducting point counts across seven prevalent land‐use types (forest‐ and fallow‐derived vanilla agroforests, woody and herbaceous fallow that are part of a shifting cultivation system, rice paddy, forest fragment and contiguous old‐growth forest). We find that old‐growth forest had the highest species richness, driven by a high share of endemics. Species richness and community composition in forest‐derived vanilla agroforest were similar to forest fragment, whereas fallow‐derived vanilla agroforest was most comparable to woody fallow. The open land‐use types herbaceous fallow and rice paddy had fewest species. Across forest fragments, vanilla agroforests, and woody fallows, endemic bird species richness was positively correlated to landscape‐scale forest cover. We conclude that both fallow‐ and forest‐derived vanilla agroforests play an important but contrasting role for bird conservation: Fallow‐derived agroforests are less valuable but take fallow land out of the shifting cultivation cycle, possibly preventing further degradation. Conversely, forest‐derived agroforests contribute to forest degradation but may avoid total loss of tree cover from forest fragments. Considering the land‐use history of agroforests may thus be a promising avenue for future research beyond the case of vanilla. Abstract in Malagasay is available with online material     

Kinetics of insulin receptor internalization and recycling in adipocytes. Shunting of receptors to a degradative pathway by inhibitors of recycling

The kinetics of receptor internalization and recycling was directly determined in adipocytes by measuring 125I-insulin binding to total, intracellular, and cell-surface insulin receptors. In the absence of insulin 90% of all receptors were on the cell-surface and 10% were intracellular. Insulin (100 ng/ml) rapidly altered this distribution by translocating surface receptors to the cell-interior through a temperature and energy dependent process. Surface-derived receptors were seen within cells as early as 30 s and accumulated intracellularly at the rate of approximately 20,000/min (t 1/2 = 2.7 min). After 6 min the size of the intracellular receptor pool plateaued (for up to 2 h), with 30% of surface receptors residing within the cell. This plateau was due to the attainment of an equilibrium between receptor uptake and recycling, since removal of insulin (to stop receptor uptake) was followed by both a rapid depletion of intracellular receptors and a a concomitant and stoichiometric reappearance of receptors on the cell-surface. Receptors were efficiently recycled, with little or no net loss observed even after 4 h of insulin treatment; however, recycling could be partially inhibited (approximately 10%) by several agents (e.g. chloroquine and Tris). Tris treatment of adipocytes in the presence of insulin led to 50% loss of surface and total receptors at 2 and 4 h, respectively. Since chloroquine prevented the decrease in total receptors, but not the loss of surface receptors, it appears that Tris impairs recycling by diverting a portion of incoming receptors to a chloroquine-inhibitable degradative site. From these results we conclude that: 1) insulin triggers endocytotic uptake of insulin-receptor complexes; 2) internalized receptors are then rapidly reinserted into the plasma membrane, and the receptors can traverse this recycling pathway within 6 min; 3) prolonged recycling does not normally result in measurable receptor loss, but when receptors are prevented from recycling, they become trapped intracellularly and are shunted to a chloroquine-sensitive degradative pathway; and 4) chloroquine and Tris are only partially effective inhibitors of receptor recycling.     

PTRN‐1/CAMSAP promotes CYK‐1/formin‐dependent actin polymerization during endocytic recycling

Cargo sorting and membrane carrier initiation in recycling endosomes require appropriately coordinated actin dynamics. However, the mechanism underlying the regulation of actin organization during recycling transport remains elusive. Here we report that the loss of PTRN‐1/CAMSAP stalled actin exchange and diminished the cytosolic actin structures. Furthermore, we found that PTRN‐1 is required for the recycling of clathrin‐independent cargo hTAC‐GFP. The N‐terminal calponin homology (CH) domain and central coiled‐coils (CC) region of PTRN‐1 can synergistically sustain the flow of hTAC‐GFP. We identified CYK‐1/formin as a binding partner of PTRN‐1. The N‐terminal GTPase‐binding domain (GBD) of CYK‐1 serves as the binding interface for the PTRN‐1 CH domain. The presence of the PTRN‐1 CH domain promoted CYK‐1‐mediated actin polymerization, which suggests that the PTRN‐1‐CH:CYK‐1‐GBD interaction efficiently relieves autoinhibitory interactions within CYK‐1. As expected, the overexpression of the CYK‐1 formin homology domain 2 (FH2) substantially restored actin structures and partially suppressed the hTAC‐GFP overaccumulation phenotype in ptrn‐1 mutants. We conclude that the PTRN‐1 CH domain is required to stimulate CYK‐1 to facilitate actin dynamics during endocytic recycling.     

Blue Native/SDS‐PAGE and iTRAQ‐Based Chloroplasts Proteomics Analysis of Nicotiana tabacum Leaves Infected with M Strain of Cucumber Mosaic Virus Reveals Several Proteins Involved in Chlorosis Symptoms

Virus infection in plants involves necrosis, chlorosis, and mosaic. The M strain of cucumber mosaic virus (M‐CMV) has six distinct symptoms: vein clearing, mosaic, chlorosis, partial green recovery, complete green recovery, and secondary mosaic. Chlorosis indicates the loss of chlorophyll which is highly abundant in plant leaves and plays essential roles in photosynthesis. Blue native/SDS‐PAGE combined with mass spectrum was performed to detect the location of virus, and proteomic analysis of chloroplast isolated from virus‐infected plants was performed to quantify the changes of individual proteins in order to gain a global view of the total chloroplast protein dynamics during the virus infection. Among the 438 proteins quantified, 33 showed a more than twofold change in abundance, of which 22 are involved in the light‐dependent reactions and five in the Calvin cycle. The dynamic change of these proteins indicates that light‐dependent reactions are down‐accumulated, and the Calvin cycle was up‐accumulated during virus infection. In addition to the proteins involved in photosynthesis, tubulin was up‐accumulated in virus‐infected plant, which might contribute to the autophagic process during plant infection. In conclusion, this extensive proteomic investigation on intact chloroplasts of virus‐infected tobacco leaves provided some important novel information on chlorosis mechanisms induced by virus infection.     

Although there is no Physical Short‐Term Scarcity of Phosphorus,its Resource Efficiency Should be Improved

The German government has adopted a law that requires sewage plants to go beyond the recovery of phosphorus from wastewater and to promote recycling. We argue that there is no physical global short‐ or mid‐term phosphorus scarcity. However, we also argue that there are legitimate reasons for policies such as those of Germany, including: precaution as a way to ensure future generations’ long‐term supply security, promotion of technologies for closed‐loop economics in a promising stage of technology development, and decrease in the current supply risk with a new resource pool.     

Novel Functions for the Endocytic Regulatory Proteins MICAL‐L1 and EHD1 in Mitosis

During interphase, recycling endosomes mediate the transport of internalized cargo back to the plasma membrane. However, in mitotic cells, recycling endosomes are essential for the completion of cytokinesis, the last phase of mitosis that promotes the physical separation the two daughter cells. Despite recent advances, our understanding of the molecular determinants that regulate recycling endosome dynamics during cytokinesis remains incomplete. We have previously demonstrated that Molecule Interacting with CasL Like‐1 (MICAL‐L1) and C‐terminal Eps15 Homology Domain protein 1 (EHD1) coordinately regulate receptor transport from tubular recycling endosomes during interphase. However, their potential roles in controlling cytokinesis had not been addressed. In this study, we show that MICAL‐L1 and EHD1 regulate mitosis. Depletion of either protein resulted in increased numbers of bi‐nucleated cells. We provide evidence that bi‐nucleation in MICAL‐L1‐ and EHD1‐depleted cells is a consequence of impaired recycling endosome transport during late cytokinesis. However, depletion of MICAL‐L1, but not EHD1, resulted in aberrant chromosome alignment and lagging chromosomes, suggesting an EHD1‐independent function for MICAL‐L1 earlier in mitosis. Moreover, we provide evidence that MICAL‐L1 and EHD1 differentially influence microtubule dynamics during early and late mitosis. Collectively, our new data suggest several unanticipated roles for MICAL‐L1 and EHD1 during the cell cycle.      

The role of caveolae and caveolin 1 in calcium handling in pacing and contraction of mouse intestine

In mouse intestine, caveolae and caveolin‐1 (Cav‐1) are present in smooth muscle (responsible for executing contractions) and in interstitial cells of Cajal (ICC; responsible for pacing contractions). We found that a number of calcium handling/dependent molecules are associated with caveolae, including L‐type Ca²⁺ channels, Na⁺‐Ca²⁺ exchanger type 1 (NCX1), plasma membrane Ca²⁺ pumps and neural nitric oxide synthase (nNOS), and that caveolae are close to the peripheral endo‐sarcoplasmic reticulum (ER‐SR). Also we found that this assemblage may account for recycling of calcium from caveolar domains to SR through L‐type Ca ⁺ channels to sustain pacing and contractions. Here we test this hypothesis further comparing pacing and contractions under various conditions in longitudinal muscle of Cav‐1 knockout mice (lacking caveolae) and in their genetic controls. We used a procedure in which pacing frequencies (indicative of functioning of ICC) and contraction amplitudes (indicative of functioning of smooth muscle) were studied in calcium‐free media with 100 mM ethylene glycol tetra‐acetic acid (EGTA). The absence of caveolae in ICC inhibited the ability of ICC to maintain frequencies of contraction in the calcium‐free medium by reducing recycling of calcium from caveolar plasma membrane to SR when the calcium stores were initially full. This recycling to ICC involved primarily L‐type Ca²⁺ channels; i.e. pacing frequencies were enhanced by opening and inhibited by closing these channels. However, when these stores were depleted by block of the sarco/endoplasmic reticulum Ca²⁺‐ATPase (SERCA) pump or calcium release was activated by carbachol, the absence of Cav‐1 or caveolae had little or no effect. The absence of caveolae had little impact on contraction amplitudes, indicative of recycling of calcium to SR in smooth muscle. However, the absence of caveolae slowed the rate of loss of calcium from SR under some conditions in both ICC and smooth muscle, which may reflect the loss of proximity to store operated Ca channels. We found evidence that these channels were associated with Cav‐1. These changes were all consistent with the hypothesis that a reduction of the extracellular calcium associated with caveolae in ICC of the myenteric plexus, the state of L‐type Ca²⁺ channels or an increase in the distance between caveolae and SR affected calcium handling.