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1.
Chemosphere ; 363: 142982, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39089338

RESUMO

The shift towards a circular economy, where waste generation is minimized through waste re-use and the development of valorization strategies, is crucial for the establishment of a low carbon, sustainable, and resource-efficient economy. However, there is a lack of strategies for re-using and valorizing specific types of waste, particularly those containing naturally occurring radioactive materials (NORM), despite the prevalence of industrial activities that produce such waste due to their chemical and radiological hazards. Living organisms, including fungi, are valuable sources of bioactive compounds with various industrial applications. In this study, we assessed the growth and metabolic profile changes of three white rot fungi species in response to low concentrations of a uranium mine effluent containing NORM and metals to explore their potential for producing biotechnologically relevant bioactive compounds. The growth rate was assessed in three different culture media, with and without the uranium mine effluent (1% V/V)), and the metabolic profile was analyzed using FTIR-ATR spectroscopy. Results suggested an improvement in growth rates in media containing the uranium mine effluent, although not statistically significant. T. versicolor showed promise in terms of bioactive compound production. The production of droplets during growth experiments and significant metabolic changes, associated with the production of bioactive compounds like laccase, melanin, and oxalic acid, were observed in T. versicolor grown in mYEPDA with the uranium mine effluent. These findings present new research opportunities for utilizing waste to enhance the biotechnological production of industrially relevant bioactive compounds and promote the development of circular economy strategies for re-using and valorizing NORM-containing waste.


Assuntos
Resíduos Industriais , Mineração , Urânio , Urânio/metabolismo , Biodegradação Ambiental , Lacase/metabolismo
2.
Molecules ; 29(13)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38999031

RESUMO

Tomatoes are well known for their impressive nutritional value among vegetables. However, the industrial processing of tomatoes generates a significant amount of waste. Specifically, 10% to 18% of the raw materials used in tomato processing become waste. This waste can seriously affect ecosystems, such as freshwater bodies, wetlands, rivers, and other natural environments, if not properly managed. Interestingly, tomato waste, specifically the skin, contains lycopene, a potent antioxidant and antimutagenic that offers a range of health benefits. This makes it a valuable ingredient in industries such as food and cosmetics. In addition, researchers are exploring the potential of lycopene in the treatment of various types of cancer. This systematic review, guided by the PRISMA 2020 methodology, examined studies exploring the possibility of tomato peel as a source of lycopene and carotenoids for cancer treatment. The findings suggest that tomato peel extracts exhibit promising anticancer properties, underscoring the need for further investigation of possible therapeutic applications. The compiled literature reveals significant potential for using tomato peel to create new cancer treatments, which could potentially revolutionize the field of oncology. This underscores the importance of continued research and exploration, emphasizing the urgency and importance of the scientific community's contribution to this promising area of study.


Assuntos
Licopeno , Neoplasias , Solanum lycopersicum , Solanum lycopersicum/química , Licopeno/química , Licopeno/farmacologia , Humanos , Neoplasias/tratamento farmacológico , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Carotenoides/uso terapêutico , Carotenoides/química , Carotenoides/farmacologia , Animais
3.
AIMS Microbiol ; 10(1): 12-40, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525040

RESUMO

A multi-stage option to address food-safety can be produced by a clearer understanding of Campylobacter's persistence through the broiler production chain, its environmental niche and its interaction with bacteriophages. This study addressed Campylobacter levels, species, genotype, bacteriophage composition/ levels in caeca, litter, soil and carcasses across commercial broiler farming practices to inform on-farm management, including interventions. Broilers were sequentially collected as per company slaughter schedules over two-years from 17 farms, which represented four commercially adopted farming practices, prior to the final bird removal (days 39-53). The practices were conventional full clean-out, conventional litter re-use, free-range-full cleanout and free-range-litter re-use. Caeca, litter and soil collected on-farm, and representative carcases collected at the processing plant, were tested for Campylobacter levels, species dominance and Campylobacter bacteriophages. General community profiling via denaturing gradient gel electrophoresis of the flaA gene was used to establish the population relationships between various farming practices on representative Campylobacter isolates. The farming practice choices did not influence the high caeca Campylobacter levels (log 7.5 to log 8.5 CFU/g), the carcass levels (log 2.5 to log 3.2 CFU/carcass), the C. jejuni/C. coli dominance and the on-farm bacteriophage presence/levels. A principal coordinate analysis of the flaA distribution for farm and litter practices showed strong separation but no obvious farming practice related grouping of Campylobacter. Bacteriophages originated from select farms, were not practice-dependent, and were detected in the environment (litter) only if present in the birds (caeca). This multifaceted study showed no influence of farming practices on on-farm Campylobacter dynamics. The significance of this study means that a unified on-farm risk-management could be adopted irrespective of commercial practice choices to collectively address caeca Campylobacter levels, as well as the potential to include Campylobacter bacteriophage biocontrol. The impact of this study means that there are no constraints in re-using bedding or adopting free-range farming, thus contributing to environmentally sustainable (re-use) and emerging (free-range) broiler farming choices.

4.
Polymers (Basel) ; 16(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38475297

RESUMO

Polymer powder bed fusion (PBF) is becoming increasingly popular for the fabrication of lightweight, high-performance parts, particularly for medical and aerospace applications. This study investigates the effect of powder re-use and material aging on the coalescence behaviour, melt flowability, and isothermal crystallisation kinetics of polyamide-12 (PA-12) powder. With increased powder re-use, a progressive reduction in melt flowability and material coalescence is observed; at 200 °C, the particle consolidation time increases from 15 s in virgin powder to 180 s in powder recovered from build 6. The observed changes in the behaviour of PA-12 were attributed to polycondensation and cross-linking; these aging phenomena also create structural defects, which hinder the rate and extent of primary crystallisation. At an isothermal crystallisation temperature of 165 °C, the crystallisation half-time increased from 12.78 min in virgin powder to 23.95 min in powder re-used across six build cycles. As a result, the commonly used Avrami model was found to be unsuitable for modelling the crystallisation behaviour of aged PA-12 powder, with the co-efficient of determination (R2) reducing from >0.995 for virgin powder to as low as 0.795 for re-used powder. On the other hand, an alternative method, the Hay model, is able to successfully track full phase transformation within re-used powder (R2 > 0.99). These results highlight the importance of selecting the most appropriate model for analysing the crystallisation kinetics of PA-12 powder re-used across multiple build cycles. This understanding is crucial for obtaining the strong mechanical properties and dimensional precision required for the fabrication of functional, end-use parts within PBF.

5.
Environ Res ; 246: 118125, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38199474

RESUMO

The excessive and uncontrollable discharge of diverse organic pollutants into the environment has emerged as a significant concern, presenting a substantial risk to human health. Among the advanced oxidation processes used for the purification of wastewater, cold plasma technology is superior in fast and effective decontamination but often fails facing mixed pollutants. To address these issues, here we develop the new conceptual approach, plasma process, and proprietary reactor that ensure, for the first time, that the efficiency of treatment (114.7%) of two mixed organic dyes, methylene blue (MB) and methyl orange (MO), is higher than when the two dyes are treated separately. We further reveal the underlying mechanisms for the energy-efficient complete degradation of the mixed dyes. The contribution of plasma-induced ROS and the distinct degradation characteristics and mechanism of pollutants in mixed treatment are discussed. The electron transfer pathway revealed for the first time suggest that the mixed pollutants reduce the overall redox potentials and facilitate electron transfer during the plasma treatment, promoting synergistic degradation effects. The integrated frameworks including both direct and indirect mechanisms provide new insights into the high-efficiency mixed-contaminant treatment. The degradation products for mixed degradation are revealed based on the identification of intermediate species. The plasma-treated water is proven safe for living creatures in waterways and sustainable fishery applications, using in vivo zebrafish model bio-toxicity assay. Overall, these findings offer a feasible approach and new insights into the mechanisms for the development of highly-effective, energy-efficient technologies for wastewater treatment and reuse in agriculture, industry, and potentially in urban water networks.


Assuntos
Poluentes Ambientais , Gases em Plasma , Poluentes Químicos da Água , Humanos , Animais , Águas Residuárias , Corantes/análise , Peixe-Zebra , Água , Poluentes Químicos da Água/análise
6.
Ther Innov Regul Sci ; 58(1): 1-10, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910271

RESUMO

Bayesian Dynamic Borrowing (BDB) designs are being increasingly used in clinical drug development. These methods offer a mathematically rigorous and robust approach to increase efficiency and strengthen evidence by integrating existing trial data into a new clinical trial. The regulatory acceptability of BDB is evolving and varies between and within regulatory agencies. This paper describes how BDB can be used to design a new randomised clinical trial including external data to supplement the planned sample size and discusses key considerations related to data re-use and BDB in drug development programs. A case-study illustrating the planning and evaluation of a BDB approach to support registration of a new medicine with the Center for Drug Evaluation in China will be presented. Key steps and considerations for the use of BDB will be discussed and evaluated, including how to decide whether it is appropriate to borrow external data, which external data can be re-used, the weight to put on the external data and how to decide if the new study has successfully demonstrated treatment benefit.


Assuntos
Projetos de Pesquisa , Teorema de Bayes , Tamanho da Amostra , Avaliação de Medicamentos
7.
Front Public Health ; 11: 1289945, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38074768

RESUMO

The COVID-19 pandemic has exemplified the importance of interoperable and equitable data sharing for global surveillance and to support research. While many challenges could be overcome, at least in some countries, many hurdles within the organizational, scientific, technical and cultural realms still remain to be tackled to be prepared for future threats. We propose to (i) continue supporting global efforts that have proven to be efficient and trustworthy toward addressing challenges in pathogen molecular data sharing; (ii) establish a distributed network of Pathogen Data Platforms to (a) ensure high quality data, metadata standardization and data analysis, (b) perform data brokering on behalf of data providers both for research and surveillance, (c) foster capacity building and continuous improvements, also for pandemic preparedness; (iii) establish an International One Health Pathogens Portal, connecting pathogen data isolated from various sources (human, animal, food, environment), in a truly One Health approach and following FAIR principles. To address these challenging endeavors, we have started an ELIXIR Focus Group where we invite all interested experts to join in a concerted, expert-driven effort toward sustaining and ensuring high-quality data for global surveillance and research.


Assuntos
COVID-19 , Animais , Humanos , COVID-19/epidemiologia , Pandemias , Fortalecimento Institucional , Disseminação de Informação
8.
Acta Vet Scand ; 65(1): 51, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38031198

RESUMO

BACKGROUND: Advanced bipolar tissue sealer/dividers provide the most reliable and efficient means of tissue dissection and blood vessel sealing in laparoscopic surgery and the techniques are continuously improved. In veterinary practice, cost-effectiveness is of major impact, leading to re-use of instruments designed and sold for single use. Two high-end devices were evaluated and compared in a highly standardized laparoscopic ovariectomy procedure in dogs: The new generation Ligasure Maryland Sealer/Divider (LMSD) with improved atraumatic curved jaw shape for delicate tissue handling and dissection and non-stick nanocoating, and the new-generation Articulating Enseal G2 (AENG2) with several proclaimed features improving surgical performance, including articulation of the forceps tip; improved tissue compression during sealing; unique offset electrode configuration; and specific nanoparticle coating minimizing thermal spread and tissue sticking. Twenty-one client-owned dogs admitted for elective laparoscopic ovariectomy were randomly assigned to one of two groups: ovariectomy using AENG2 on the left ovary and LMSD in the right ovary or vice-versa. Procedural video recordings were used to assess ovarian ligament fat score, smoke formation, occurrence of bleeding, and excision duration. Excised tissues were examined histopathologically and collateral thermal damage was scored in three anatomic zones: suspensory ligament, vascular pedicle, and uterine junction. Tissue sealers were used repeatedly following standardized cleaning protocol with instrument washing machine and ethylene oxide gas sterilization and the number of uses until device failure was recorded. RESULTS: Excision times were significantly increased for AENG2 (median 01:35 min) compared to LMSD (median 01:00 min). Minor hemorrhage from incomplete sealing occurred in 3 sites in 2 patients (2x AENG2, 1x LMSD) and was not significantly different between groups. Smoke production as scored on videos and thermal tissue damage scores on histopathology also did not differ between AENG2 and LMSD. Both vessel sealers could be re-used repeatedly. CONCLUSION: AENG2 provides a good alternative to LMSD in laparoscopic ovariectomy, with only minor differences in measured variables. Subjectively, the articulating feature of AENG2 did not improve surgical performance in laparoscopic ovariectomy and the use of LMSD appeared more straight-forward for this specific procedure. However, differences in operating these devices may be subject to personal preference.


Assuntos
Laparoscopia , Animais , Cães , Feminino , Laparoscopia/veterinária , Maryland , Ovariectomia/veterinária , Instrumentos Cirúrgicos/veterinária , Útero
9.
Eur J Psychotraumatol ; 14(2): 2254118, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37703089

RESUMO

BACKGROUND: The FAIR data principles aim to make scientific data more Findable, Accessible, Interoperable, and Reusable. In the field of traumatic stress research, FAIR data practices can help accelerate scientific advances to improve clinical practice and can reduce participant burden. Previous studies have identified factors that influence data sharing and re-use among scientists, such as normative pressure, perceived career benefit, scholarly altruism, and availability of data repositories. No prior study has examined researcher views and practices regarding data sharing and re-use in the traumatic stress field. OBJECTIVE: To investigate the perspectives and practices of traumatic stress researchers around the world concerning data sharing, re-use, and the implementation of FAIR data principles in order to inform development of a FAIR Data Toolkit for traumatic stress researchers. METHOD: A total of 222 researchers from 28 countries participated in an online survey available in seven languages, assessing their views on data sharing and re-use, current practices, and potential facilitators and barriers to adopting FAIR data principles. RESULTS: The majority of participants held a positive outlook towards data sharing and re-use, endorsing strong scholarly altruism, ethical considerations supporting data sharing, and perceiving data re-use as advantageous for improving research quality and advancing the field. Results were largely consistent with prior surveys of scientists across a wide range of disciplines. A significant proportion of respondents reported instances of data sharing and re-use, but gold standard practices such as formally depositing data in established repositories were reported as infrequent. The study identifies potential barriers such as time constraints, funding, and familiarity with FAIR principles. CONCLUSIONS: These results carry crucial implications for promoting change and devising a FAIR Data Toolkit tailored for traumatic stress researchers, emphasizing aspects such as study planning, data preservation, metadata standardization, endorsing data re-use, and establishing metrics to assess scientific and societal impact.


Traumatic stress researchers worldwide responding to a survey held generally positive views on data sharing, endorsing scholarly altruism and pro-sharing ethical considerations, and rating data re-use as useful for advancing the field.While many respondents reported instances of sharing or re-using data, gold standard practices such as formally depositing data in established repositories were reported as infrequent.Barriers to data sharing and re-use included time constraints, funding, and a lack of familiarity with practices to make data more Findable, Accessible, Interoperable, and Re-usable (FAIR).


Assuntos
Disseminação de Informação , Otimismo , Humanos , Projetos de Pesquisa
11.
Front Genet ; 14: 1086802, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37007976

RESUMO

Modern AI supported research holds many promises for basic and applied science. However, the application of AI methods is often limited because most labs cannot, on their own, acquire large and diverse datasets, which are best for training these methods. Data sharing and open science initiatives promise some relief to the problem, but only if the data are provided in a usable way. The FAIR principles state very general requirements for useful data sharing: they should be findable, accessible, interoperable, and reusable. This article will focus on two challenges to implement the FAIR framework for human neuroscience data. On the one hand, human data can fall under special legal protection. The legal frameworks regulating how and what data can be openly shared differ greatly across countries which can complicate data sharing or even discourage researchers from doing so. Moreover, openly accessible data require standardization of data and metadata organization and annotation in order to become interpretable and useful. This article briefly introduces open neuroscience initiatives that support the implementation of the FAIR principles. It then reviews legal frameworks, their consequences for accessibility of human neuroscientific data and some ethical implications. We hope this comparison of legal jurisdictions helps to elucidate that some alleged obstacles for data sharing only require an adaptation of procedures but help to protect the privacy of our most generous donors to research … our study participants. Finally, it elaborates on the problem of missing standards for metadata annotation and introduces initiatives that aim at developing tools to make neuroscientific data acquisition and analysis pipelines FAIR by design. While the paper focuses on making human neuroscience data useful for data-intensive AI the general considerations hold for other fields where large amounts of openly available human data would be helpful.

12.
Animals (Basel) ; 13(8)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37106968

RESUMO

Improving nutrient management in grazing system dairy farms requires determining nutrient flows through animals, the placement of cows within farms and potential for collection, and the re-use and loss of nutrients. We applied a model incorporating data collected at a range of temporal and spatial scales to quantify nutrient excretion in all locations that lactating herds visited on five days over a year on 43 conventional and organic grazing system dairy farms. The calculated nutrient loads excreted by cows in different places were highly skewed; while N, P and K deposited loads were consistent across the year, S, Ca and Mg loads varied between sampling times and seasons. The greatest mean and range in nutrient loads were deposited in paddocks, with the smallest amounts deposited in dairy sheds. All excreted nutrient loads increased with farm and herd sizes and milk production. Mean daily loads of 112, 15, 85, 11, 22 and 13 kg of N, P, K, S, Ca and Mg were deposited by the herds which, when standardised to a 305-day lactation, amounted to 24, 4, 20, 3, 5 and 3 t excreted annually, respectively. In addition to routine manure collection in dairy sheds, ensuring collection and recycling of nutrients excreted on feed pads and holding areas would decrease potential nutrient losses by 29% on average. Non-collected, recycled nutrients were disproportionately returned to paddocks in which cows spent time overnight, and except for S and Ca, nutrient loading rates were greater than rates applied as fertilisers. These data demonstrate the extent of excreted nutrients in grazing dairy systems and indicate the need to account for these nutrients in nutrient management plans for Australian dairy farms. We propose incorporating excretion data in current budgeting tools using data currently collected on most Australian grazing system dairy farms.

13.
J Proteome Res ; 22(3): 729-742, 2023 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-36577097

RESUMO

The availability of proteomics datasets in the public domain, and in the PRIDE database, in particular, has increased dramatically in recent years. This unprecedented large-scale availability of data provides an opportunity for combined analyses of datasets to get organism-wide protein abundance data in a consistent manner. We have reanalyzed 24 public proteomics datasets from healthy human individuals to assess baseline protein abundance in 31 organs. We defined tissue as a distinct functional or structural region within an organ. Overall, the aggregated dataset contains 67 healthy tissues, corresponding to 3,119 mass spectrometry runs covering 498 samples from 489 individuals. We compared protein abundances between different organs and studied the distribution of proteins across these organs. We also compared the results with data generated in analogous studies. Additionally, we performed gene ontology and pathway-enrichment analyses to identify organ-specific enriched biological processes and pathways. As a key point, we have integrated the protein abundance results into the resource Expression Atlas, where they can be accessed and visualized either individually or together with gene expression data coming from transcriptomics datasets. We believe this is a good mechanism to make proteomics data more accessible for life scientists.


Assuntos
Proteoma , Proteômica , Humanos , Proteoma/análise , Proteômica/métodos , Perfilação da Expressão Gênica , Bases de Dados Factuais , Espectrometria de Massas/métodos , Bases de Dados de Proteínas
14.
Waste Manag Res ; 41(1): 98-116, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36068940

RESUMO

A circular economy (CE) aims to reduce waste and encourages keeping products, components, and materials circulating in the economy. Furthermore, following the European waste hierarchy, preparing for re-use (PfR) is regarded as a better waste management option than recycling. Nevertheless, too many products with a reuse potential end up as waste. This includes residuals from products that have no major value and are therefore not demanded by the current system. As a result, products are prematurely recycled. This contradicts both the priority order of the waste hierarchy and the principles of a CE. This article investigates the potential of and constraints to reusing products that are disposed of at municipal recycling stations. It aims to improve our understanding of these issues and offers possible solutions that could enable municipal waste companies to transition from waste to resource management and reach the upper levels of the waste hierarchy, preparing waste for re-use. Interviews with relevant stakeholders, desk studies and knowledge obtained from participating in waste conferences over the past 3 years are all used to analyze PfR practice at five municipal waste management companies in Denmark. Pioneers with respect to circularity in the waste sector, which have been experimenting with and initiating PfR schemes concerning a range of products, including building materials, furniture, white goods and bicycles, are considered because they support the inner cycles of the CE. However, results reveal that the current transition consists of complex processes connected to an ambivalent legal framework and struggles over access and rights to resources. Further, a more coherent conceptual understanding of PfR is needed as the current understanding has a too narrow focus on restoring product value rather than coupling PfR processes to the market. Thus, challenges to achieving higher PfR rates seem to go beyond engaging in strategic partnerships, creating financial incentives and setting separate targets for PfR. Consequently, a more holistic investigation appears to be necessary to deepen our understanding of processes of resource management and use and the contestation that exists over these. Furthermore, a wider mapping of the actors operating in the tension area of PfR, including their willingness to cooperate and negotiate a zone of agreement, could prove beneficial to practitioners and policy developers alike.


Assuntos
Gerenciamento de Resíduos , Gerenciamento de Resíduos/métodos , Reciclagem/métodos , Materiais de Construção , Dinamarca
15.
Polymers (Basel) ; 14(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36432952

RESUMO

High performances of thermosets deriving from their covalent intermolecular cross-link bonds result in their low recyclability hindering the full exploitation of a truly circular approach for cured thermosets. In this experimental work, the recyclability of a bio-based fully recyclable epoxy resin using a mild chemical recycling process was demonstrated. The recycled polymer obtained was fully characterized to ascertain its structure and properties. MALDI (Matrix-Assisted Laser Desorption/Ionization), GPC (Gel Permeation Chromatography) and NMR (Nuclear Magnetic Resonance) spectroscopy to determine the chemical structure of the recycled polymer were used. The thermomechanical properties of the cured virgin network and of the recycled product obtained were measured by DSC (Differential Scanning Calorimetry) and DMA (Dynamic Mechanical Analysis). Thermogravimetric analysis of the recycled polymer was also performed. The recycled polymer was transformed into a polyurethane by reacting it with an isocyanate. The synthetized polyurethane obtained therefrom was thoroughly characterized by thermogravimetric analysis. This approach proved the possibility to up-scale the recycled product making it available for novel applications exploiting its re-use.

16.
Nanomaterials (Basel) ; 12(15)2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35957128

RESUMO

To move away from fossil fuels, the electrochemical reaction plays a critical role in renewable energy sources and devices. The anodic oxygen evolution reaction (OER) is always coupled with these reactions in devices but suffers from large energy barriers. Thus, it is important for developing efficient OER catalysts with low overpotential. On the other hand, there are large amounts of metals in electronic waste (E-waste), especially various transition metals that are promising alternatives for catalyzing OER. Hence, this work, which focuses on upcycling Class II BaTiO3 Multilayer Ceramic Capacitors, of which two trillion were produced in 2011 alone. We achieved this by first using a green solvent extraction method that combined the ionic liquid Aliquat® 336 and hydrochloride acid to recover a mixed solution of Ni, Fe and Cu cations, and then using such a solution to synthesize high potential catalysts NiFe hydroxide and NiCu hydroxide for OER. NiFe-hydroxide has been demonstrated to have faster OER kinetics than the NiCu-hydroxide and commercial c-RuO2. In addition, it showed promising results after the chronopotentiometry tests that outperform c-RuO2.

17.
Polymers (Basel) ; 14(5)2022 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-35267834

RESUMO

In the present study, recyclability of Laser PP CP 75 polypropylene powder from Diamond Plastics GmbH was determined by characterizing and comparing the used powder after each cycle with material from previous cycles and with fresh powder. The melt flow index of Laser PP CP 75 was affected by recycling since it was observed to change by 30.62% after the 8th 100% re-use cycle, a lower value than PA 12 of 66.04%, for the 6th re-use cycle. Parts printed with virgin Laser PP CP 75 had an average dimensional error of 3.02% (virgin material) and 4.06% after the 4th 100% re-use cycle, which raises concerns about the commercial viability of the material. After the 4th re-use cycle, the printed parts had distorted edges and failed to print after the 9th print cycle. Lastly, tensile testing revealed a skewed bell-shaped curve of strength versus the number of recycles with the highest ultimate tensile strength occurring for the second 100% re-use cycle (7.4 MPa). The curves for elastic modulus and percentage elongation were inverted with minimum points for the 2nd 100% re-use cycle. Overall, the experimental work confirmed that the properties of polypropylene powder were affected by recycling in polymer laser sintering, but the powder exhibited superior characteristics upon recycling to those of the predominantly used PA 12 powder.

18.
Food Res Int ; 151: 110825, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34980376

RESUMO

Coffee cup quality is primarily determined by the type and variety of green beans chosen and the roasting regime used. Furthermore, green coffee beans are not only the starting point for the production of all coffee beverages but also are a major source of revenue for many sub-tropical countries. Green bean quality is directly related to its biochemical composition which is influenced by genetic and environmental factors. Post-harvest, on-farm processing methods are now particularly recognised as being influential to bean chemistry and final cup quality. However, research on green coffee has been limited and results are fragmented. Despite this, there are already indications that multiple factors play a role in determining green coffee chemistry - including plant cultivation/fruit ripening issues and ending with farmer practices and post-harvest storage conditions. Here, we provide the first overview of the knowledge determined so far specifically for pre-factory, green coffee composition. In addition, the potential of coffee waste biomass in a biobased economy context for the delivery of useful bioactives is described as this is becoming a topic of growing relevance within the coffee industry. We draw attention to a general lack of consistency in experimentation and reporting and call for a more intensive and united effort to build up our knowledge both of green bean composition and also how perturbations in genetic and environmental factors impact bean chemistry, crop sustainability and ultimately, cup quality.


Assuntos
Coffea , Bebidas , Café
19.
Part Fibre Toxicol ; 19(1): 1, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34983569

RESUMO

BACKGROUND: Assessing the safety of engineered nanomaterials (ENMs) is an interdisciplinary and complex process producing huge amounts of information and data. To make such data and metadata reusable for researchers, manufacturers, and regulatory authorities, there is an urgent need to record and provide this information in a structured, harmonized, and digitized way. RESULTS: This study aimed to identify appropriate description standards and quality criteria for the special use in nanosafety. There are many existing standards and guidelines designed for collecting data and metadata, ranging from regulatory guidelines to specific databases. Most of them are incomplete or not specifically designed for ENM research. However, by merging the content of several existing standards and guidelines, a basic catalogue of descriptive information and quality criteria was generated. In an iterative process, our interdisciplinary team identified deficits and added missing information into a comprehensive schema. Subsequently, this overview was externally evaluated by a panel of experts during a workshop. This whole process resulted in a minimum information table (MIT), specifying necessary minimum information to be provided along with experimental results on effects of ENMs in the biological context in a flexible and modular manner. The MIT is divided into six modules: general information, material information, biological model information, exposure information, endpoint read out information and analysis and statistics. These modules are further partitioned into module subdivisions serving to include more detailed information. A comparison with existing ontologies, which also aim to electronically collect data and metadata on nanosafety studies, showed that the newly developed MIT exhibits a higher level of detail compared to those existing schemas, making it more usable to prevent gaps in the communication of information. CONCLUSION: Implementing the requirements of the MIT into e.g., electronic lab notebooks (ELNs) would make the collection of all necessary data and metadata a daily routine and thereby would improve the reproducibility and reusability of experiments. Furthermore, this approach is particularly beneficial regarding the rapidly expanding developments and applications of novel non-animal alternative testing methods.


Assuntos
Metadados , Projetos de Pesquisa , Bases de Dados Factuais , Reprodutibilidade dos Testes
20.
Waste Manag Res ; 40(7): 1039-1046, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34666577

RESUMO

This study investigates the feasibility of material recycling for retrieved gillnets from the Baltic Sea collected during a campaign of the World Wildlife Fund (WWF) Germany. Fragments from the material were analysed by Fourier transform infrared (FTIR) spectroscopy revealing polyamide 6 (PA6), polypropylene (PP) and polyethylene terephthalate (PET) in net material, swim lines and sink lines, respectively. A visual examination by microscope found large quantities of minerals attached to the surface of the material as well as in knots and loops of the polymer structure. Ash tests showed that a pre-treatment of the material including sorting, shredding, density separation and washing allows to reduce the mineral content from more than 45% of the total to 1.1%. However, for a separation by density, it is important that the entangled fibres can move freely. This is a major challenge for a primary or secondary mechanical recycling because a substantial fibre length reduction is required for the small polymer fibres down to a diameter of 20 µm. Another challenge for all kinds of recycling is the presence of lead lines in gillnets. Automated technology for removing these does not exist until now. A manual removal is indispensable to limit the level of contamination. Due to the complex pre-treatment and the elevated heavy metal concentrations also a tertiary or feedstock recycling seems not to be a possible pathway for retrieved gillnets. Yet, other options such as a primary recycling in concrete or bitumen additives or quaternary recycling via incineration may be conceivable alternatives. But there are also some arguments against these options. Better product design must be the goal to prevent plastic pollution and establish a functioning circular economy. In this context, the heavy metal contamination by abandoned, lost or otherwise discarded fishing gear (ALDFG) must be stopped.


Assuntos
Pesqueiros , Caça , Plásticos , Polímeros , Reciclagem
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