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Fossil-plastics or paper? Or for that matter, bio-plastics and paper? This is a well-entrenched question in academic research, industrial, social and policy-making circles. As environmental life-cycle analyses (or more appropriately, sustainability analyses) show time and again, no single product or process or mode of operation is a ‘total villain’. There are goods and bads, and at times, more of the one than the other. This paper, which is based on a course-report written by the first author at Karlstad University (Sweden), restricts itself to a review of publications which have opted to compare paper bags with low density polyethylene (LDPE) plastic bags, on the basis of their environmental impacts. Environmental impact categories include the global warming potential, energy demand, fossil fuel depletion, water usage, acidification, eutrophication, and a range of toxicities – human, terrestrial, freshwater-aquatic and marine-aquatic. The articles were obtained through Google Scholar, read and reviewed to glean the results presented therein. The ‘What’, ‘How’ and ‘Where’, so to say were studied carefully to understand the reasons behind any differences or similarities detected. On the basis of this focused review, even though no new knowledge is being added, the common belief that the paper bag is environmentally superior to the LDPE alternative is further consolidated. However, if one focuses on water usage and would assign a high weightage to that environmental impact, LDPE perhaps may score a few ‘brownie points’ over paper. One must also not forget that plastics (LDPE in this instance) can be recycled without significant deterioration in its functional properties. In a circular economy (the bioeconomy part of which gradually will expand over time), while introducing more and more bio-based products into the technosphere by way of trans-materialization is recommended, plastics will still continue to exist – albeit in much smaller amounts – and it would be perfectly fine if the degree of recycling is augmented significantly. Speaking of a holistic sustainability analysis, the socio-economic aspects of a choice between LDPE and paper bags must also be factored in, and studied. Much-desired change happens when the top-down meets the bottom-up somewhere midway.

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This study seeks to profile the shoppers' propensity to reuse shopping bags and the type of shopping bags they reuse on the basis of demographics. The study used an observation method to record the consumers' shopping habits and a short questionnaire to record the participants' demographics. A binary regression analysis and a multinomial regression analysis were used to analyse data. The results indicated that the mature aged, women, and low income shoppers were more likely to practice reuse of plastic shopping bags than their respective counterparts. There were no statistically significant differences in the likelihood of young aged shoppers compared to mature aged shoppers and low income shoppers compared to high income shoppers using cotton bags than plastic bags. There were also no statistically significant differences in the likelihood of young aged shoppers compared to mature aged shoppers and male shoppers compared to female shoppers using paper bags than plastic bags. However, the results indicated a statically significant result in how males compared to females differed in their using of cotton bags than plastic bags and a statistically significant result in how low income shoppers compared to high income shoppers differed in their use of paper bags than plastic bags. [ABSTRACT FROM AUTHOR]

The recycling of bio-waste from households is an essential factor in achieving the recycling quotas for municipal waste laid down by the EU. A major problem is posed by impurities in the bio-waste collected, such as plastics, metals and glass. It is virtually impossible for compost producers to produce quality-assured compost from bio-waste with an impurity content of more than 3 wt%OS. The draft of the new Austrian Compost Ordinance stipulates a limit of 2 wt%OS of interfering substances in accepted bio-waste. A rapid measurement method has been developed and comprehensively validated for the immediate on-site checking of contaminant content at the bio-waste bin or in a vehicles. Data on the type and amount of impurities collected in the course of sorting analyses carried out over several years in 10 selected areas in Styria, Austria showed an average impurity content of 2.1 wt%OS. This impurity content can be considered representative for rural and urban communities in Austria. Among the interfering substances, plastics predominate, at 53%, of which pre-collection bags made of plastics form the highest proportion. A more detailed examination of pre-collection bags shows a higher proportion of use of biodegradable plastic bags, which have become more numerous in recent years in the more rural communities. In order to reduce mis-sorting, the effect of a wide variety of measures on citizens was tested in selected areas. Here, the distribution of paper bags as well as the threat of a cost increase due to special collections in combination with distribution of these bags were the methods with the greatest effect. Motivational letters and the threat of special collections, however, showed no significant result. [ABSTRACT FROM AUTHOR]

Jambu (Acmella oleracea [(L.) RK Jansen]) is a vegetable of great importance in the Amazonian region; it can be found in the daily life of the citizens of the State of Pará (Brazil), since it is part of traditional dishes such as duck in tucupi and tacacá sauce. Although jambu is widely cultivated, agronomic information about its management remains scarce. The aim of the current study was to analyze the physiological potential of jambu seeds stored in different packages and environments. The investigated packages comprised glass, Eppendorf tubes, plastic bags and paper bags conditioned in refrigerator and under natural conditions in Castanhal, Pará, for 360 days. Seed germination, first germination count, emergence seedlings, germination and emergence speed index, and seedling dry weight and length were the variables evaluated at 40-day intervals. The experimental design was completely randomized, with four replicates of 50 seeds per treatment. Jambu seeds were only influenced by the environment where they were stored; the ones stored under natural conditions recorded decreasing behavior for the investigated variables until they reached zero, after 280 storage days. It was possible to conclude that the physiological potential of jambu seeds stored in refrigerator was better conserved. [ABSTRACT FROM AUTHOR]

Purpose: The pervasive use of plastics, coupled with inadequate waste management systems in many countries, has led to widespread leakage of plastics into the environment. In South Africa, the predominant type of shopping bags are single-use plastic bags; but paper, biodegradable plastic and re-usable bags have emerged as alternatives. To compare these alternatives in terms of environmental impacts across the whole product life cycle, we carried out a cradle-to-grave life cycle assessment (LCA) of 16 shopping bag types available in South Africa. Methods: The comparison includes single-use plastic, bioplastic and paper bags, as well as re-usable bags (typically made from plastic in South Africa). The functional unit was based on the estimated annual volume of groceries purchased per capita. An attributional LCA was carried out using the ReCiPe 2016 Midpoint(H) method, with 18 mid-point impact categories. In addition, given the lack of an impact category for plastic pollution in existing methods, we developed a mid-point indicator based on the persistence of plastics (and other materials) leaked to the environment (Persistence of leaked material, PersistenceLM). Specific attention was placed on modelling end-of-life and waste management in the South African context. Economic-based allocation at the point of substitution was used to apportion environmental impacts to virgin and recyclate material, and the production of recyclate was modelled using system expansion. Results and discussion: Re-usable bag types, specifically the 70 µm High Density Polyethylene (HDPE) and non-woven Polyester bags, had the lowest environmental impacts for all indicators, except PersistenceLM. Paper and biodegradable plastic bags had a lower PersistenceLM impact as compared to the petro-based plastic bags, and therefore may be preferable in terms of avoiding plastics accumulating in the environment. The re-usable bags need to be used at least 3 to 10 times to offer lower environmental impacts than single-use ones. Among the single-use bags, biodegradable bags made from imported Polybutylene Adipate Terepthalate (PBAT) plus starch showed the lowest environmental impacts across all impact categories, including PersistenceLM, followed by the Paper bag. The single-use 24 µm HDPE bag (HDPE_24) with no recycled content had the highest overall environmental impacts, while increasing the recycled content reduced overall environmental impacts by up to 52%. Compared to other countries, the high environmental impacts of plastic bags in South Africa can largely be attributed to the coal-to-liquids process used for polymer production, which is intensive in terms of both energy and raw materials. [ABSTRACT FROM AUTHOR]

This article describes the study of the eco-impact of plastic and paper bags using the life cycle impact assessment (LCIA) technique under three different options: usage and disposal criteria with the existing usage behavior to reuse and governmental policies to recycle (option1), usage and disposal criteria as per consumers' perceptions if systems are in place (option2) and usage and disposal criteria in case of absence of recycling systems (option3). The first stage, which was the baseline for other options, comprised of the study of the eco-impact of plastic and paper bags in the manufacturing phase, without considering the usage and disposal phases. LCIA was performed by the Eco-indicator 99, a damage oriented method for LCIA in SIMAPRO 7.1. The single score values calculated by the Eco-indicator '99 were considered as a directive to compare the environmental impact made by plastic and paper bags and a detailed explanation of the results is provided in this article. The next stage was the study of the eco-impact of these bags including their usage and disposal phases. This was undertaken with the three different options as stated above and the results derived were compared with the results derived from the baseline study, which is the main focus of the study under discussion. The values for usage and end-of-life phases were obtained from the questionnaire survey of different user groups of shopping bags in China, Hong Kong and India. The results of this study show that the eco-impact of plastic and paper bags was very high if there were no usage and disposal options provided. When the eco- impact values from options of existing possibilities and consumers' perception were compared, the eco- impact value was lower in option 1 in all the three countries for both types of bags, which is mainly attributed to the fact that in option 1, a higher percentage of reuse is preferred to recycle and disposal to landfill categories. Also the eco-impact of these two types of bags was studied with and without the presence of recycling systems in China, India and Hong Kong, where the eco-impact was lower due to the presence of recycling systems. The results indicate that a higher percentage of reuse could significantly trim down the eco-impact of plastic and paper bags. Consumers' perceptions and usage behaviors in connection with respective government's policies and implementation of recycling systems could be highly decisive in reducing the eco-impact of plastic and paper shopping bags. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Entomología is the property of Universidad del Valle and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Using observational data on consumer carryout bag usage, we measure the effects of disposable bag policies on disposable and reusable bag demand. Our results show that plastic bag bans coupled with paper bag fees decrease total disposable bag demand but lead to significant increases in paper bag consumption. We compare our results to a study on bag fees and find that both policies lead to similar increases in reusable bag usage. However, the success of bans versus fees in discouraging disposable bag usage is contingent upon the types and prices of bags that stores choose to sell in lieu of disposable plastic. [ABSTRACT FROM AUTHOR]

Plastic bags have recently been introduced as an alternative to multiwall Kraft paper bags in packaging milk powder in 25-kg sizes as it is thought that plastic bags are more durable and would preserve the quality of milk powders during storage better than paper bags. However, there is little scientific information available on the performance of plastic bags for milk powder storage. The aim of this study was to compare the properties of skimmed milk powder (SMP) packaged in plastic or paper bags. Commercially produced and packaged SMP in 25-kg plastic or paper bags was stored at 37°C and 90% relative humidity. Samples were analysed at intervals (0, 45, 90 and 135 days) for moisture, water activity, lactic acid content, pH, insolubility index, bulk density, flowability, dispersibility and particle size. The magnitude of change in the majority of SMP properties measured during storage suggests that plastic bags are similar to paper bags in maintaining milk powder quality during storage. [ABSTRACT FROM AUTHOR]

Plastic pollution is among the many socio-economic and environmental dilemmas that have engulfed Pakistan. The exponentially increasing consumption of plastic and the difficulty of dealing with its waste has compelled the government to impose a ban on the use of non-biodegradable plastics. This ban has made Pakistan the 128th country to curb plastic usage through punitive measures. However, the country lacks cheap and sustainable alternatives for plastic bags and bottles, which form the most significant chunk of plastic waste. This research study aims to analyze and propose alternatives that can replace these plastic bags and bottles without compromising the lifestyle of citizens. The aim of this study is two-fold; first, it employs Fuzzy VIKOR, a Multi-Criteria Decision-Making technique for comparison and prioritization of alternatives, i.e., Conventional Plastic bags, Paper bags, and Bioplastic bags, with respect to multiple aspects of sustainability. Secondly, it performs a cost–benefit analysis of a Bioplastic plant, with a focus on the production of biodegradable plastic bottles. The MCDM analysis prioritized the bioplastic bags, followed by paper bags and the least preferable alternative turned out to be conventional plastic bags. The cost–benefit analysis indicated that although the production of bioplastic bottles instead of conventional plastic bottles would lead to the reduction of detrimental environmental impacts, however, currently it is not financially profitable for the industrialists to switch to bioplastics. Therefore, it is recommended that government authorities should incorporate carbon taxes and subsidize the sustainable development sector, which would, in turn, lead to the reduction of plastic consumption and waste in society. [ABSTRACT FROM AUTHOR]

The white pollution caused by waste plastic brings heavy pollution and a variety of potential hazards on the ecological environment and human survival. It provided the important ways of utilization which could rationally eliminate environmental pollution of plastic wastes. In this work, a novel TENG based on the waste plastic bags (WPB) and the polytetrafluoroethylene (PTFE) film (WPB-TENG) to power the pencil-on-paper strain sensor for flexible vertical interconnection was proposed. The PTFE film and WPB film serve as the triboelectric pairs, and the conductive copper play the role of conductive electrode. The WPB-TENG device and pencil-on-paper strain sensor can prepared through the sample process. The Voc and Isc of WPB-TENG can reach 251 V and 34.1 µA, respectively. And the maximum power can arrive at 1.57 mW, which can support many electronic devices. 40 commercial LEDs can be driven by the WP-TENG. The self-powered pencil-on-paper strain sensor can detect various strain changes without external source. This research has realized the integration of power devices and functional sensor devices. [ABSTRACT FROM AUTHOR]

[Objectives] The effects of bag types on the appearance and internal quality of red Massh grapefruit were studied. [Methods] Outer-yellow inner-black double-layer pomelo special paper bags, white single-layer paper bags, yellow plastic film bags, and red plastic film bags were used to cover the fruit of red Massh grapefruit. With the fruit free of bagging as a control, the effects of fruit bags with different materials were compared. [Results] The four kinds of fruit bag treat ments effectively reduced pests and diseases, and increased the good fruit rate, and the effects of paper bag treatments were better than those of film bags. The outer- yellow inner-black double-layer pomelo special paper bags had good air permeability and were easy to operate. The bagged fruit had a smooth and beautiful surface and showed a unique uniform pink color after removing the bags. The fruit had moderate sour and sweet flavor and good overall benefits. It is worthy of popular-ization and application. [Conclusions] Fruit bagging has good economic benefits, and it is recommended to use the outer-yellow inner-black double-layer pomelo special paper bags. [ABSTRACT FROM AUTHOR]

[Objectives J The effects of bag types on the appearance and internal quality of red Massh grapefruit were studied. [Methods] Outer-yellow inner-black double-layer pomelo special paper bags, white single-layer paper bags, yellow plastic film bags, and red plastic film bags were used to cover the fruit of red Massh grapefruit. With the fruit free of bagging as a control, the effects of fruit bags with different materials were compared. [ Results] The four kinds of fruit bag treatments effectively reduced pests and diseases, and increased the good fruit rate, and the effects of paper bag treatments were better than those of film bags. The outer- yellow inner-black double-layer pomelo special paper bags had good air permeability and were easy to operate. The bagged fruit had a smooth and beautiful surface and showed a unique uniform pink color after removing the bags. The fruit had moderate sour and sweet flavor and good overall benefits. It is worthy of popularization and application. [Conclusions] Fruit bagging has good economic benefits, and it is recommended to use the outer-yellow inner-black double-layer pomelo special paper bags. [ABSTRACT FROM AUTHOR]

This study was conducted to examine consumers' response, changes in their shopping behaviour and the effectiveness of the 'No Free Plastic Bag' campaign after almost a decade consumers were charged RM0.20 for using plastic bags. Data was collected from 122 respondents who answered an online questionnaire. The findings indicated that bringing your own shopping bag is not yet the culture in Malaysia despite that majority of consumers were aware of the campaign. Behavioural change is low as 62.3% of respondents routinely forget to bring their own shopping bags. More than half of the respondents (57.3%) are still willing to pay RM0.20 for a plastic bag. The findings of this research also revealed that consumers are too depending on retailers' green initiatives such as providing them with paper bags and boxes. Through this study, mass media plays a crucial role in disseminating information and creating environmental awareness among consumers. Many consumers voiced their support for a stricter regulation and to increase the current fee for each plastic bag purchased. [ABSTRACT FROM AUTHOR]

A detailed characterization of municipal solid waste (MSW) beyond a standard compositional analysis may offer insights useful for improving waste management systems. The present paper contributes to the scarce literature in the field by presenting new data from a rapidly developing Central Asian city, the capital of Kazakhstan, Nur-Sultan. Three sampling campaigns (each 1 week long) have been conducted at the city landfill over a 1-year period (2018–2019), and a detailed characterization for selected waste components and sub-components has been performed. The major fractions of MSW were organics (46.3%), plastics (15.2%), paper (12.8%), and diapers (5.9%). The detailed composition analysis showed high LDPE (low-density polyethylene) content (5.5%) mostly comprised of plastic bags (4.5%), transparent glass (3.2%), pharmaceuticals (0.4%), and fine (i.e., < 12 mm) organic fraction content (29%). The MSW generation rate of Nur-Sultan was estimated as 1.47 kg capita−1 day−1 based on the field collection as well as literature data. Among sustainable waste management recommendations addressed for Nur-Sultan and applicable to other cities in Central Asia, composting is recommended due to high organics fraction in MSW and its great potential to reduce the landfilled waste volume and to help valorizing the waste. [ABSTRACT FROM AUTHOR]

In Accra's migrant neighbourhoods called zongos, personal photo archives are carefully kept in plastic bags or albums, revealing the migratory biographies of living and late family members and the various social activities in which they engage. This paper unpacks the archives of three women in the zongos, interweaving the indexical values of the photographs with an analysis of their material historicity of exchange and haptic encounters. I argue that in the collections, fragments of the zongo women's personhood are both materially and ontologically diffracted, as such performing personhood in line with gendered zongo grammars and values of extended networks of affiliation, affect, and generosity. Such performance is controlled by the owners of the collections, thus creating openings for self-representation and social mobility, but also for contesting gendered grammars. [ABSTRACT FROM AUTHOR]

Transparent objects are encountered frequently in our daily lives, yet recognizing them poses challenges for conventional vision sensors due to their unique material properties, not being well perceived from RGB or depth cameras. Overcoming this limitation, thermal infrared cameras have emerged as a solution, offering improved visibility and shape information for transparent objects. In this paper, we present TRansPose, the first large-scale multispectral dataset that combines stereo RGB-D, thermal infrared (TIR) images, and object poses to promote transparent object research. The dataset includes 99 transparent objects, encompassing 43 household items, 27 recyclable trashes, 29 chemical laboratory equivalents, and 12 non-transparent objects. It comprises a vast collection of 333,819 images and 4,000,056 annotations, providing instance-level segmentation masks, ground-truth poses, and completed depth information. The data was acquired using an FLIR A65 thermal infrared camera, two Intel RealSense L515 RGB-D cameras, and a Franka Emika Panda robot manipulator. Spanning 87 sequences, TRansPose covers various challenging real-life scenarios, including objects filled with water, diverse lighting conditions, heavy clutter, non-transparent or translucent containers, objects in plastic bags, and multi-stacked objects. Supplementary material can be accessed from the following link: https://sites.google.com/view/transpose-dataset. [ABSTRACT FROM AUTHOR]

Growing popularity of self-service in retail stores and increasing associated shrinkage presents an urgent need for computer-vision-based product recognition in the area of self-checkouts. The article focuses on individual product recognition using automated workflow in images collected from retail store self-checkouts. The interest of this research lies exclusively in the recognition of barcodeless products—ones that present a challenge of being identified quickly and qualitatively at self-checkouts. Image sets representative of retail store product distribution do not exist as of the time of writing to the authors' knowledge. Images collected by exploiting self-checkout events often contain products partially covered by customer body parts, inside semi-transparent plastic bags, or not present in the area of interest. Due to the huge assortment of products that varies between stores and changes frequently, manual image labeling, filtering and long training time are unpractical. The proposed method investigates the need for automated steps to eliminate empty images and eliminate images where product visibility is unsatisfactory. Authors achieved 80.5±1.2% classification accuracy on a real-world dataset of 194 products using automatic workflow. The ablation studies proved the need for image filtering in both training and inference workflows. The neural network architecture tuned to the self-checkout dataset proved to outperform well-known networks: the suggested architecture's training time is a fraction of ImageNet's best EfficientNet and accuracy is slightly better. The suggested method generalization is proved on comparable products dataset Fruits 360, where 99.6% accuracy was achieved—comparable or better than other authors. [ABSTRACT FROM AUTHOR]

The article focuses on a physical model designed for beginning students to help them understand the classification system for matter. The model is constructed using two large reclosable plastic bags for each student. Each large plastic bag contains eight smaller reclosable bags. Each small bag contains an assortment of colored vinyl-coated paper clips, some of which are attached to each other in specific ways as described. The larger bags can be labeled as set I and set II, with the smaller bags being labeled A through H. It is easier for the students to organize their work if the two sets of bags are labeled using different colors. The model helps students to build accurate conceptual pictures of what constitutes molecules, compounds, mixtures, and pure substances.

Contactless and non-destructive measuring tools can facilitate the moisture monitoring of bagged or bulk grain during transportation and storage. However, accurate target recognition and size prediction always impede the effectiveness of contactless monitoring in actual use. This paper developed a novel 3D reconstruction method upon multi-angle point clouds using a binocular depth camera and a proper Yolo-based neural model to resolve the problem. With this method, this paper developed an embedded and low-cost monitoring system for the in-warehouse grain bags, which predicted targets' 3D size and boosted contactless grain moisture measuring. Identifying and extracting the object of interest from the complex background was challenging in size prediction of the grain silo-bag on a conveyor. This study first evaluated a series of Yolo-based neural network models and explored the most appropriate neural network structure for accurately extracting the grain bag. In point-cloud processing, this study constructed a rotation matrix to fuse multi-angle point clouds to generate a complete one. This study deployed all the above methods on a Raspberry Pi-embedded board to perform the grain bag's 3D reconstruction and size prediction. For experimental validation, this study built the 3D reconstruction platform and tested grain bags' reconstruction performance. First, this study determined the appropriate positions (−60°, 0°, 60°) with the least positions and high reconstruction quality. Then, this study validated the efficacy of the embedded system by evaluating its speed and accuracy and comparing it to the original Torch model. Results demonstrated that the NCNN-accelerated model significantly enhanced the average processing speed, nearly 30 times faster than the Torch model. The proposed system predicted the objects' length, width, and height, achieving accuracies of 97.76%, 97.02%, and 96.81%, respectively. The maximum residual value was less than 9 mm. And all the root mean square errors were less than 7 mm. In the future, the system will mount three depth cameras for achieving real-time size prediction and introduce a contactless measuring tool to finalize grain moisture detection. [ABSTRACT FROM AUTHOR]

Copyright of TEME: Casopis za Društvene Nauke is the property of TEME: Casopis za Drustvene Nauke and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Koinonía: Revista Arbitrada Interdisciplinaria de Ciencias de la Educación, Turismo, Ciencias Sociales y Económicas, Ciencias del Agro y Mar y Ciencias Exactas y Aplicadas is the property of Fundacion Koinonia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The amount of research and publications related to microplastic pollution has been steadily increasing in recent years, but at the same time, our current knowledge on the topic is still based on occasional point measurements. As a result of these point measurements, it becomes obvious that new research areas and disciplines are also connected to the topic of microplastics. Various biotic and abiotic processes can cause microplastics to enter the environment and spread within it. All of these mechanisms can arise from the moisture conditions of the tested medium, temperature differences, or even from the decomposing and transforming activities of microorganisms. The rise of biodegradable and compostable plastic bags can also be considered a source of this kind since polymer products labelled as environmentally friendly can be identified as secondary sources during their decomposition processes. Therefore, both industrial and household compost can contain microscopic polymer residues, the application of which involves a potential risk of environmental pollution. In recent years, several international studies have dealt with various aspects of the degradation of these products, including the use of problems caused by residual microplastics and their environmental effects. The focus of our paper is not on the development of a new scientific methodology but a summary of the current situation formed through research results dealing with the current environmental safety and environmental health risks of microplastic pollution caused by biodegradable polymers. [ABSTRACT FROM AUTHOR]