Diverse Streams Research Articles

Environmental sustainability assessment of different end-of-life scenarios for the pulper rejects produced in the paper recycling process

Resource recovery from wastes through recycling processes promotes near-zero-waste residue business models and supports the circular economy's goals by facilitating the closure of loops in industrial systems and reducing energy and resource consumption as well as pollutant emissions. However, the approach is sustainable only when the waste can be valorized, and the environmental impact of the recycling is lower with respect to other end-of-life (EOL) scenarios. Due to the diversity and complexity of wastes streams, these aspects need to be evaluated on a case-by-case basis.This study focuses on a mechanical recycling process for pulper rejects, a mixed waste stream generated during recycled paper production, with two aims: (1) to define a feasible mechanical recycling process and (2) to evaluate its environmental performance through life cycle assessment (LCA) compared to the most common EOL treatments, such as incineration with energy recovery and landfilling. ReCiPe 2016 H method was used to estimate the environmental impacts of all scenarios, adopting both midpoint and endpoint approaches, on a functional unit (FU) defined as 1000 kg of pulper rejects. The LCA results indicate that the pulper rejects recycling is always preferable to landfilling across all impact categories considered. On the contrary, in comparison to incineration, the best environmental option depends on the specific impact category considered. In particular, recycling is the best EOL alternative in terms of impacts on global warming, with an impact 33 % lower, but it is not the most sustainable one in terms of fossil resource consumption, mainly due to the amount of energy required during all steps of the recycling process, while allowing the recovery of materials that would otherwise be lost. Currently, it is not possible to identify an overall ‘winner’ between incineration with energy recovery and recycling for the pulper rejects because the most environmentally sound alternative varies depending on the priority given to different environmental issues. Therefore, further improvements of the pulper rejects recycling pathway performances are required to make the process even more efficient and competitive.

Effects of increasing complexity in biogeochemistry and hydrology on variability of total phosphorus concentration in models of a low flow subtropical wetland

In south Florida, treatment wetlands known as stormwater treatment areas (STAs) are used to reduce total phosphorus (P) concentrations of agricultural and urban stormwater runoff before discharging into the Everglades Protection Area. The remobilization of P from immobile forms stored in soils and litter has the potential to negatively affect STA treatment efficiency. Phosphorus biogeochemical dynamics in one of the best performing Everglades STA flow-ways, STA-2 FW1, were modeled mechanistically and empirically using diverse streams of data (flow, total P in water, soil, floc, vegetation). We evaluated the effect of P wetland uptake and hydrologic transport on STA-2 FW1's simulated outflow P concentrations by juxtaposing varying complexities of biogeochemistry (1–2 vs 13 wetland P pools) and hydrology (uniform vs. nonuniform flow) models. The uniform flow model considers a constant velocity with each time step while velocity in the nonuniform flow model is a stochastic ensemble mimicking spatial flow variability. When coupled with uniform or nonuniform flow, the variability of water column P concentration in the most complex model was significantly different from the two simple biogeochemistry models, although it was lower compared to data in all models. Regardless of the biogeochemistry model, uniform versus nonuniform transport did not affect simulated outflow P concentration. Significant interaction effects between the choices of biogeochemistry and hydrology models were observed. The most complex model included specific compartments for vegetation, floc and soil and reproduced data trends of more P accumulated in upstream areas that decreases with increasing distance away from inflow. Modeling biotic mechanisms and tracking P in vegetation and sediments, confirms the importance of including biogeochemistry in understanding and predicting outflow P concentrations in STA-2 FW1. This modeling tool could be used to guide future STA data collection needs and inform Everglades STA performance optimization efforts.

Unhealthy sleep assimilation

Abstract Migrant health advantages, the ‘healthy immigrant effect’, erode over time, leading to what is known as unhealthy assimilation. Health-related behaviours are central to unhealthy assimilation, and here we focus on an understudied and central part of our daily time: sleep. Building on diverse streams of literature, we conceptualize and empirically study the sleep assimilation patterns of immigrants. With data from Germany, we demonstrate that immigrants sleep significantly more than natives upon arrival, while their sleep ‘advantage’ dissipates with years spent in the host country. We also explore the heterogeneity of the sleep assimilation process by gender, education, wages, work schedules, and job physical intensity.

How Controlling Can Coordinate Strategic Management at Car Dealerships

This article describes a strategic management approach that car dealerships can successfully implement with internal resources. The article departs from the premise that there still is no central organizing paradigm for strategic management. Strategic management is understood as a discipline with diverse streams that highlight different aspects of reality that, taken together, explain a part of what strategic management in practice is. Therefore, this article is based on the process-oriented model of Al-Laham et al (2017) and the professional and academic experience of the author. The outcome of this article is that controlling is highly qualified to coordinate strategic management at car dealerships. However, car dealerships tend to assign strategic management tasks to external consultants. As a result, strategic plans are often not implemented. The value of this article is to provide a management approach for car dealerships to coordinate strategic management with internal resources and keep a tight grip on strategy implementation.

The heat is on: Predicting urban stream temperature responses to summer storms

AbstractShort‐term increases in stream temperature in response to storm events have frequently been observed in urban areas, highlighting the need for improved understanding of the factors influencing urban stream temperature. Urban land cover complexity and infrastructure designed for rapid water routing to the sewer system create a direct link between storm events and water release processes, influencing urban stream temperature responses. This study aims to identify predictors of diverse stream temperature response patterns to summer storms. We analysed 403 storm events from six urban and semi‐urban catchments along the US East Coast using dynamic time warping to identify archetype patterns of stream temperature responses. We further disentangled observed stream temperature increase patterns to reveal the drivers associated with ‘heat pulses’, which are characterized by a rapid but high‐magnitude temperature increase followed by a sharp temperature drop at the start of the hydrograph increase. Our results show that stream temperature patterns were event‐specific and linked to pre‐event conditions and rainfall–runoff characteristics, with the shape of the hydrograph and rainfall–runoff response identified as the most important determinators of the observed temperature response patterns. Ponded surface waters and storm drains, as well as cooler water from the shallow subsurface, were identified as potential sources contributing to temperature patterns. These findings have important implications for understanding urban hydrology and the contributions of different source zones in urban catchments. Specifically, our results suggest that stream temperature may serve as a cost‐effective tracer providing information about urban water sources and pathways, thus aiding in the understanding of complex urban hydrology.

INCOME DIVERSIFICATION, PROFITABILITY, AND RISK IN ISLAMIC BANKING IN INDONESIA

This study investigates the factors that affect income diversification and the associated risk in Indonesian Islamic banking. Panel regression is used to examine the correlation between risk factors, including primary operating revenue, fee-based income, internal and external factors, and the profitability of Islamic banks. Panel regression analysis has been conducted on the data from 2012-2016 to determine the factors that affect profitability and risk. The results show that pretax profit, after-tax profit as a proportion of total assets, and after-tax profit as a percentage of total equity react differently to income diversification. According to the findings, an increase in profit before taxes can be expected as the number and diversity of a company's revenue streams continue to expand. This indicates that the financial health of Islamic banks improves when they have access to many revenue streams. Furthermore, the standard deviation of baseline income shows that diversifying sources of income has little effect on internal risk.

Effects of environmental factors and ecological integrity on semiaquatic bugs (Hemiptera: Heteroptera: Gerromorpha) diversity in Cerrado streams

Effects of environmental factors and ecological integrity on semiaquatic bugs (Hemiptera: Heteroptera: Gerromorpha) diversity in Cerrado streams

Non-random species loss under human disturbance increases the nestedness component of macroinvertebrate beta diversity in tropical streams

In the perspective for partitioning beta diversity proposed by Baselga (2010), species loss was assumed to increase the nestedness component. As species loss is generally non-random under human disturbance, we hypothesised that non-random species loss tends to increase both taxonomic and functional nestedness components, and that such increases can be explained by environmental gradients. We surveyed the macroinvertebrates in two pairs of tropical degraded stream groups (with strong human disturbance) and reference stream groups (with much less human disturbance). We measured and compared both taxonomic and functional beta diversities and their nestedness components between sampling sites in and among the reference and degraded streams. Macroinvertebrate communities indeed underwent significant non-random loss from the reference to degraded streams, which is linked to the traits of taxa responding to disturbances (e.g., body size, tolerance, and feeding habit). Under non-random loss, both taxonomic and functional beta diversities significantly increased between the reference and degraded streams, mainly due to an increase in their nestedness components. In particular, the nestedness component dominated the functional beta diversity. As expected, taxonomic and functional beta diversities and their nestedness components were explained by environmental distance, specially by the variation of environmental variables such total nitrogen and water velocity. Our study provides evidence at a regional scale for non-random species loss increasing nestedness components of not only taxonomic but also functional beta diversities, and strongly suggests paying attention to reference streams for the protection of regional biodiversity in the tropics.

Social innovation in non-profit organizations: a measurement scale

Social innovation has emerged as an outstanding topic in a situation in which industrial economies are translating into knowledge and service-based societies. Research efforts have been focused on identifying the different theoretical approaches of this fragmented concept, but comprehensive instruments for measuring it are noticeably lacking. Combining a literature review and a quantitative-based research with 201 non-profit organizations (NPO), this study develops and tests a measurement scale for assessing the extent to which a particular initiative undertaken by the NPO (a project, program, process, product or any other activity) is a social innovation. A thorough revision of the diverse streams that have approached this construct allowed us to define the domain specification, as well as to generate a pool of items and assure the content validity of the scale. Different statistical analyses were used to assess its dimensionality, reliability and validity. This scale can be employed by practitioners and policymakers to verify the extent to which NPO initiatives satisfy a social problem, in a new and sustainable way, and with the improvement of social behaviors or relationships, as well as to identify relevant gaps that need to be addressed to effectively set priorities and implement SI strategies and policies.

Salinization and sedimentation drive contrasting assembly mechanisms of planktonic and sediment-bound bacterial communities in agricultural streams.

Agriculture is the most dominant land use globally and is projected to increase in the future to support a growing human population but also threatens ecosystem structure and services. Bacteria mediate numerous biogeochemical pathways within ecosystems. Therefore, identifying linkages between stressors associated with agricultural land use and responses of bacterial diversity is an important step in understanding and improving resource management. Here, we use the Mississippi Alluvial Plain (MAP) ecoregion, a highly modified agroecosystem, as a case study to better understand agriculturally associated drivers of stream bacterial diversity and assembly mechanisms. In the MAP, we found that planktonic bacterial communities were strongly influenced by salinity. Tolerant taxa increased with increasing ion concentrations, likely driving homogenous selection which accounted for ~90% of assembly processes. Sediment bacterial phylogenetic diversity increased with increasing agricultural land use and was influenced by sediment particle size, with assembly mechanisms shifting from homogenous to variable selection as differences in median particle size increased. Within individual streams, sediment heterogeneity was correlated with bacterial diversity and a subsidy-stress relationship along the particle size gradient was observed. Planktonic and sediment communities within the same stream also diverged as sediment particle size decreased. Nutrients including carbon, nitrogen, and phosphorus, which tend to be elevated in agroecosystems, were also associated with detectable shifts in bacterial community structure. Collectively, our results establish that two understudied variables, salinity and sediment texture, are the primary drivers of bacterial diversity within the studied agroecosystem, whereas nutrients are secondary drivers. Although numerous macrobiological communities respond negatively, we observed increasing bacterial diversity in response to agricultural stressors including salinization and sedimentation. Elevated taxonomic and phylogenetic bacterial diversity likely increases the probability of detecting community responses to stressors. Thus, bacteria community responses may be more reliable for establishing water quality goals within highly modified agroecosystems that have experienced shifting baselines.

The role of the environment and connectivity with large rivers and streams on local fish diversity of tropical headwater streams

The role of the environment and connectivity with large rivers and streams on local fish diversity of tropical headwater streams

Asynchronous Event Processing with Local-Shift Graph Convolutional Network

Event cameras are bio-inspired sensors that produce sparse and asynchronous event streams instead of frame-based images at a high-rate. Recent works utilizing graph convolutional networks (GCNs) have achieved remarkable performance in recognition tasks, which model event stream as spatio-temporal graph. However, the computational mechanism of graph convolution introduces redundant computation when aggregating neighbor features, which limits the low-latency nature of the events. And they perform a synchronous inference process, which can not achieve a fast response to the asynchronous event signals. This paper proposes a local-shift graph convolutional network (LSNet), which utilizes a novel local-shift operation equipped with a local spatio-temporal attention component to achieve efficient and adaptive aggregation of neighbor features. To improve the efficiency of pooling operation in feature extraction, we design a node-importance based parallel pooling method (NIPooling) for sparse and low-latency event data. Based on the calculated importance of each node, NIPooling can efficiently obtain uniform sampling results in parallel, which retains the diversity of event streams. Furthermore, for achieving a fast response to asynchronous event signals, an asynchronous event processing procedure is proposed to restrict the network nodes which need to recompute activations only to those affected by the new arrival event. Experimental results show that the computational cost can be reduced by nearly 9 times through using local-shift operation and the proposed asynchronous procedure can further improve the inference efficiency, while achieving state-of-the-art performance on gesture recognition and object recognition.

Probing the Morphology and Mobility of Amines in Porous Silica CO2 Sorbents by 1H T1–T2 Relaxation Correlation NMR

Molecular and oligomeric amines supported in porous oxide supports are a promising class of CO2 sorbent materials studied for CO2 removal from diverse streams such as flue gas and ambient air. Among the various amines investigated, low molecular weight, hyperbranched poly(ethyleneimine) (PEI), and tetraethylenepentamine (TEPA) are among the most extensively studied. While macroscopic structure–performance relationships relating the support structure, amine loading, and other factors affecting CO2 sorption capacities and kinetics have been developed, structural and dynamic information about the organic amine phase in the porous support is less plentiful. The structure and mobility of amines impregnated in the pores of porous supports directly impact gas sorption, as the accessibility of amine sites in the pores directly relates to amine distribution in the pores and overall pore filling as well as the dynamics of the amine chains. Here, we prepare a family of mesoporous silica SBA-15 materials containing varying loadings of oligomeric (PEI) and molecular (TEPA) amines. 1H T1–T2 relaxation correlation solid-state NMR experiments are used to characterize the structural and dynamic properties of the confined amines. Both TEPA and PEI are shown to form multiple different domains in the pores, each with distinguishable dynamic properties. TEPA and PEI form more rigid layers around the silica support walls at lower organic loading fractions, characterized by lower mobilities, followed by the formation of more mobile domains less engaged in pore wall interactions at higher loadings. TEPA shows faster mobilities than PEI because of its lower molecular weight. TEPA also appears to more easily transfer between domains within the pores, leading to generally faster CO2 uptake rates with higher sorption capacities, while PEI located closer to the pore walls remained much less mobile and is thus less engaged in CO2 capture.

Evaluation of the Relationship between Stream Habitat Quality and Taxa and Trait Richness and Diversity in Piedmont Streams in North Carolina

As impervious cover increases with urban development, stream channels are degraded by increased stormwater runoff, which negatively impacts stream habitat quality and benthic macroinvertebrate diversity. We examined the relationship between stream habitat diversity and aquatic insect taxa and trait richness and diversity at the watershed scale in 30 streams, covering a gradient of stream habitat quality. We then quantified the relationship between taxa and trait richness and diversity and seven microhabitats at the reach scale in ten streams with high habitat quality. We found that both taxa richness and diversity declined at a greater rate than trait richness and diversity along an in-stream habitat diversity gradient. Taxa richness was positively correlated with pools, runs, backwater, leaf packs, and riffles, while trait richness was positively correlated with runs, small wood, and riffles. Taxa diversity was positively correlated with pools and leaf packs while trait diversity was positively correlated with runs, leaf packs, small wood, and riffles. An indicator species analysis revealed that specific taxa and traits were associated with specific microhabitats or combinations of microhabitats. By correlating the taxa in urban streams with specific microhabitats, we can better evaluate the success of stream restoration in restoring stream function and in stimulating benthic macroinvertebrate recovery.

Correction to: Macroinvertebrate diversity and rarity in non-glacial Alpine streams

Correction to: Macroinvertebrate diversity and rarity in non-glacial Alpine streams

Gender differences in the stability of trust and risk-taking

The individual willingness to trust is compared to the inclination to take lottery risk in six distinct scenarios, controlling the return distributions. Trust responds to changes in the admissible return levels, but exhibits significantly smaller responsiveness to return expectations compared to parallel risk-taking. Paired comparisons suggest that the investors sacrifice 5% of the expected payoff to trust anonymous responders. Trust is more calculated and volatile for males, while appearing relatively stable for females. The results connect with evidence regarding physiological differences between trust and risk-taking, and in addition suggest that trust is more of a distinctive trait for females compared to males. The paper broadly discusses the results and their implications, connecting to diverse streams in the trust literature.

Model‐informed health system reorganization during emergencies

The COVID‐19 pandemic presented the world to a novel class of problems highlighting distinctive features that rendered standard academic research and participatory processes less effective in properly informing public health interventions in a timely way. The urgency and rapidity of the emergency required tight integration of novel and high‐quality simulation modeling with public health policy implementation. By introducing flexibility and agility into standard participatory processes, we aligned the modeling effort with the imposed reality of the emergency to rapidly develop a regional system dynamics (SD) model integrating diverse streams of data that could reliably inform both health system restructuring and public health policy. Using Lombardy data, our SD model was able to generate early projections for the diffusion of the pandemic in neighbor Ticino. Later, it projected the timing and size of peak patient demand. Our work also supported the need for reorganization of the healthcare system and volume flexibility strategies increasing hospital capacity (e.g., intensive care unit [ICU] and ward beds, medical and nursing staff, and oxygen supply) in Ticino. Counterfactual analyses quantify the impact of the decisions supported by our interventions. Our research contributes to our understanding of volume flexibility strategies used by healthcare organizations during emergencies, highlighting the critical role played by available response time in the deployment of strategies that either prioritize critical services or leverage available resources. It also contributes to the literature on participatory systems modeling by describing a flexible and agile participatory process that was successfully deployed in a rapidly evolving high‐stakes emergency.

Thermal pyrolysis of waste versus virgin polyolefin feedstocks: The role of pressure, temperature and waste composition

Due to the complexity and diversity of polyolefinic plastic waste streams and the inherent non-selective nature of the pyrolysis chemistry, the chemical decomposition of plastic waste is still not fully understood. Accurate data of feedstock and products that also consider impurities is, in this context, quite scarce. Therefore this work focuses on the thermochemical recycling via pyrolysis of different virgin and contaminated waste-derived polyolefin feedstocks (i.e., low-density polyethylene (LDPE), polypropylene (PP) as main components), along with an investigation of the decomposition mechanisms based on the detailed composition of the pyrolysis oils. Crucial in this work is the detailed chemical analysis of the resulting pyrolysis oils by comprehensive two-dimensional gas chromatography (GC × GC) and ICP-OES, among others. Different feedstocks were pyrolyzed at a temperature range of 430–490 °C and at pressures between 0.1 and 2 bar in a continuous pilot-scale pyrolysis unit. At the lowest pressure, the pyrolysis oil yield of the studied polyolefins reached up to 95 wt%. The pyrolysis oil consists of primarily α-olefins (37–42 %) and n-paraffins (32–35 %) for LDPE pyrolysis, while isoolefins (mostly C9 and C15) and diolefins accounted for 84–91 % of the PP-based pyrolysis oils. The post-consumer waste feedstocks led to significantly less pyrolysis oil yields and more char formation compared to their virgin equivalents. It was found that plastic aging, polyvinyl chloride (PVC) (3 wt%), and metal contamination were the main causes of char formation during the pyrolysis of polyolefin waste (4.9 wt%).

An open-access T-BAS phylogeny for emerging Phytophthora species.

Phytophthora species cause severe diseases on food, forest, and ornamental crops. Since the genus was described in 1876, it has expanded to comprise over 190 formally described species. There is a need for an open access phylogenetic tool that centralizes diverse streams of sequence data and metadata to facilitate research and identification of Phytophthora species. We used the Tree-Based Alignment Selector Toolkit (T-BAS) to develop a phylogeny of 192 formally described species and 33 informal taxa in the genus Phytophthora using sequences of eight nuclear genes. The phylogenetic tree was inferred using the RAxML maximum likelihood program. A search engine was also developed to identify microsatellite genotypes of P. infestans based on genetic distance to known lineages. The T-BAS tool provides a visualization framework allowing users to place unknown isolates on a curated phylogeny of all Phytophthora species. Critically, the tree can be updated in real-time as new species are described. The tool contains metadata including clade, host species, substrate, sexual characteristics, distribution, and reference literature, which can be visualized on the tree and downloaded for other uses. This phylogenetic resource will allow data sharing among research groups and the database will enable the global Phytophthora community to upload sequences and determine the phylogenetic placement of an isolate within the larger phylogeny and to download sequence data and metadata. The database will be curated by a community of Phytophthora researchers and housed on the T-BAS web portal in the Center for Integrated Fungal Research at NC State. The T-BAS web tool can be leveraged to create similar metadata enhanced phylogenies for other Oomycete, bacterial or fungal pathogens.

The cooler the better: Increased aquatic hyphomycete diversity in subtropical streams along a neotropical latitudinal gradient

The cooler the better: Increased aquatic hyphomycete diversity in subtropical streams along a neotropical latitudinal gradient