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1.
J Hazard Mater ; 470: 134242, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626686

RESUMO

The high moisture content and the potential presence of hazardous organic compounds (HOCs) and metals (HMs) in sewage sludge (SS) pose technical and regulatory challenges for its circular economy valorisation. Thermal treatments are expected to reduce the volume of SS while producing energy and eliminating HOCs. In this study, we integrate quantitative analysis of SS concentration of 12 HMs and 61 HOCs, including organophosphate flame retardants (OPFRs) and per- and poly-fluoroalkyl substances (PFAS), with life-cycle assessment to estimate removal efficiency of pollutants, climate change mitigation benefits and toxicological effects of existing and alternative SS treatments (involving pyrolysis, incineration, and/or anaerobic digestion). Conventional SS treatment leaves between 24 % and 40 % of OPFRs unabated, while almost no degradation occurs for PFAS. Thermal treatments can degrade more than 93% of target OPFRs and 95 % of target PFAS (with the rest released to effluents). The different treatments affect how HMs are emitted across environmental compartments. Conventional treatments also show higher climate change impacts than thermal treatments. Overall, thermal treatments can effectively reduce the HOCs emitted to the environment while delivering negative emissions (from about -56 to -111 kg CO2-eq per tonne of sludge, when pyrolysis is involved) and producing renewable energy from heat integration and valorization.

2.
J Pathol Inform ; 13: 100014, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35251753

RESUMO

Although the laboratory information system has largely solved the problem of storing anatomic pathology reports and disseminating their contents across the healthcare system, the retrospective query of anatomic pathology reports remains an area for improvement across laboratory information system vendors. Our institution desired the ability to query our repository of anatomic pathology reports for clinical, operational, research, and educational purposes. To address this need, we developed a full-text anatomic pathology search tool using the business intelligence software, Tableau. Our search tool allows users to query the 333,685 anatomic pathology reports from our institutional clinical relational database using the business intelligence tool's built-in regular expression functionality. Users securely access the search tool using any web browser, thereby avoiding the cost of installing or maintaining software on users' computers. This tool is laboratory information system vendor agnostic and as many institutions already subscribe to business intelligence software, we believe this solution could be easily reproduced at other institutions and in other clinical departments.

3.
Bioresour Technol ; 328: 124833, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33611017

RESUMO

Variations in lignocellulosic feedstock composition can influence conversion performance of bioethanol production, but such effects are overlooked in several studies that rely on standard conversion factors. This study investigates the effects of seven lignocellulosic feedstocks (belonging to the categories energy crops, forest and agricultural residues) on mass, carbon, water and energy balances for biochemical bioethanol production, including a comparison of individual process step yields. We find that overall bioethanol yields vary considerably, ranging between 19.0 and 29.0%, 27.3 and 46.2%, and 19.0 and 31.0%, for energy and carbon efficiency, respectively. The highest yields are found for switchgrass, which has the largest carbohydrate content, and the lowest for forest residues (spruce). Feedstock composition also affects water and carbon balances. Overall, the type of biomass influences conversion performances, thereby calling for explicit representation of the effects of biomass types in technical, economic and environmental assessment studies of bioethanol production.


Assuntos
Biocombustíveis , Etanol , Biomassa , Lignina
4.
Biotechnol Biofuels ; 12: 239, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31624501

RESUMO

BACKGROUND: Microalgae are 10 to 20 times more productive than the current agricultural biodiesel producing oleaginous crops. However, they require larger energy supplies, so that their environmental impacts remain uncertain, as illustrated by the contradictory results in the literature. Besides, solar radiation is often too high relative to the photosynthetic capacity of microalgae. This leads to photosaturation, photoinhibition, overheating and eventually induces mortality. Shadowing microalgae with solar panels would, therefore, be a promising solution for both increasing productivity during hotter periods and producing local electricity for the process. The main objective of this study is to measure, via LCA framework, the energy performance and environmental impact of microalgae biodiesel produced in a solar greenhouse, alternating optimal microalgae species and photovoltaic panel (PV) coverage. A mathematical model is simulated to investigate the microalgae productivity in raceways under meteorological conditions in Sophia Antipolis (south of France) at variable coverture percentages (0% to 90%) of CIGS solar panels on greenhouses constructed with low-emissivity (low-E) glass. RESULTS: A trade-off must be met between electricity and biomass production, as a larger photovoltaic coverture would limit microalgae production. From an energetic point of view, the optimal configuration lies between 10 and 20% of PV coverage. Nevertheless, from an environmental point of view, the best option is 50% PV coverage. However, the difference between impact assessments obtained for 20% and 50% PV is negligible, while the NER is 48% higher for 20% PV than for 50% PV coverage. Hence, a 20% coverture of photovoltaic panels is the best scenario from an energetic and environmental point of view. CONCLUSIONS: In comparison with the cultivation of microalgae without PV, the use of photovoltaic panels triggers a synergetic effect, sourcing local electricity and reducing climate change impacts. Considering an economic approach, low photovoltaic panel coverage would probably be more attractive. However, even with a 10% area of photovoltaic panels, the environmental footprint would already significantly decrease. It is expected that significant improvements in microalgae productivity or more advanced production processes should rapidly enhance these performances.

5.
Mol Cell ; 67(4): 646-658.e3, 2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28781232

RESUMO

In miRNA-mediated gene silencing, the physical interaction between human Argonaute (hAgo) and GW182 (hGW182) is essential for facilitating the downstream silencing of the targeted mRNA. GW182 can interact with hAgo via three of the GW/WG repeats in its Argonaute-binding domain: motif-1, motif-2, and the hook motif. The structure of hAgo1 in complex with the hook motif of hGW182 reveals a "gate"-like interaction that is critical for GW182 docking into one of hAgo1's tryptophan-binding pockets. We show that hAgo1 and hAgo2 have a single GW182-binding site and that miRNA binding increases hAgo's affinity to GW182. With target binding occurring rapidly, this ensures that only mature RISC would be recruited for silencing. Finally, we show that hGW182 can recruit up to three copies of hAgo via its three GW motifs. This may explain the observed cooperativity in miRNA-mediated gene silencing.


Assuntos
Proteínas Argonautas/metabolismo , Autoantígenos/metabolismo , Fatores de Iniciação em Eucariotos/metabolismo , Inativação Gênica , MicroRNAs/metabolismo , RNA Guia de Cinetoplastídeos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Proteínas Argonautas/química , Proteínas Argonautas/genética , Autoantígenos/química , Autoantígenos/genética , Sítios de Ligação , Ligação Competitiva , Cristalografia por Raios X , Fatores de Iniciação em Eucariotos/química , Fatores de Iniciação em Eucariotos/genética , Humanos , MicroRNAs/química , MicroRNAs/genética , Simulação de Acoplamento Molecular , Mutação , Conformação de Ácido Nucleico , Ligação Proteica , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas , RNA Guia de Cinetoplastídeos/química , RNA Guia de Cinetoplastídeos/genética , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Células Sf9 , Relação Estrutura-Atividade , Transfecção
6.
Sci Total Environ ; 505: 833-43, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25461086

RESUMO

Gasoline is the second most consumed fuel in Chile, accounting for 34% of the total fuel consumption in transportation related activities in 2012. Chilean refineries process more than 97% of the total gasoline commercialized in the national market. When it comes to evaluating the environmental profile of a Chilean process or product, the analysis should consider the characteristics of the Chilean scenario for fuel production and use. Therefore, the identification of the environmental impacts of gasoline production turns to be very relevant for the determination of the associated environmental impacts. For this purpose, Life Cycle Assessment has been selected as a useful methodology to assess the ecological burdens derived from fuel-based systems. In this case study, five subsystems were considered under a "well-to-wheel" analysis: crude oil extraction, gasoline importation, refinery, gasoline storage and distribution/use. The distance of 1 km driven by a middle size passenger car was chosen as functional unit. Moreover, volume, economic and energy-based allocations were also considered in a further sensitivity analysis. According to the results, the main hotspots were the refining activities as well as the tailpipe emissions from car use. When detailing by impact category, climate change was mainly affected by the combustion emissions derived from the gasoline use and refining activities. Refinery was also remarkable in toxicity related categories due to heavy metals emissions. In ozone layer and mineral depletion, transport activities played an important role. Refinery was also predominant in photochemical oxidation and water depletion. In terms of terrestrial acidification and marine eutrophication, the combustion emissions from gasoline use accounted for large contributions. This study provides real inventory data for the Chilean case study and the environmental results give insight into their influence of the assessment of products and processes in the country. Moreover, they could be compared with production and distribution schemes in other regions.


Assuntos
Monitoramento Ambiental , Indústrias Extrativas e de Processamento/estatística & dados numéricos , Gasolina , Dióxido de Carbono/análise , Chile , Mudança Climática , Efeito Estufa , Petróleo , Emissões de Veículos/análise
7.
Electron. j. biotechnol ; 16(3): 13-13, May 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-684011

RESUMO

Background: Bioethanol is produced mainly from sugar cane and corn. In the last years it has been subject of debate due to the effects in food prices and land use change. The use of lignocellulosic materials for bioethanol production, such as agroindustry, forestry and municipal residues, wood or dendroenergetic species, has been proposed as a sustainable way for producing this biofuel. The design of a sustainable process for producing bioethanol requires a methodological approach whereby economical, environmental and social criteria are systematically integrated from the early stages of process design. Results: Until now a methodology for guiding the design of a sustainable process for bioethanol production is not available, and there are just a few studies on this subject. Moreover, with the recent global concerns on climate change, developed technologies have been confronted with additional requirements to validate their sustainability. In this sense, the inclusion of sustainability criteria on process design becomes necessary for defining a systematic methodology to select the most appropriate operations in the process stages to achieve a sustainable bioethanol production. Conclusions: A description of the stages for the production of bioethanol from lignocellulosic materials is provided in this review and the main findings in relation to the more important sustainability indicators are presented.


Assuntos
Etanol/metabolismo , Biocombustíveis/análise , Lignina/metabolismo , Estágios do Ciclo de Vida
8.
Radiat Res ; 179(1): 76-88, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23216524

RESUMO

Spinal cord injury is a devastating condition with no effective treatment. The physiological processes that impede recovery include potentially detrimental immune responses and the production of reactive astrocytes. Previous work suggested that radiation treatment might be beneficial in spinal cord injury, although the method carries risk of radiation-induced damage. To overcome this obstacle we used arrays of parallel, synchrotron-generated X-ray microbeams (230 µm with 150 µm gaps between them) to irradiate an established model of rat spinal cord contusion injury. This technique is known to have a remarkable sparing effect in tissue, including the central nervous system. Injury was induced in adult female Long-Evans rats at the level of the thoracic vertebrae T9-T10 using 25 mm rod drop on an NYU Impactor. Microbeam irradiation was given to groups of 6-8 rats each, at either Day 10 (50 or 60 Gy in-beam entrance doses) or Day 14 (50, 60 or 70 Gy). The control group was comprised of two subgroups: one studied three months before the irradiation experiment (n = 9) and one at the time of the irradiations (n = 7). Hind-limb function was blindly scored with the Basso, Beattie and Bresnahan (BBB) rating scale on a nearly weekly basis. The scores for the rats irradiated at Day 14 post-injury, when using t test with 7-day data-averaging time bins, showed statistically significant improvement at 28-42 days post-injury (P < 0.038). H&E staining, tissue volume measurements and immunohistochemistry at day ≈ 110 post-injury did not reveal obvious differences between the irradiated and nonirradiated injured rats. The same microbeam irradiation of normal rats at 70 Gy in-beam entrance dose caused no behavioral deficits and no histological effects other than minor microglia activation at 110 days. Functional improvement in the 14-day irradiated group might be due to a reduction in populations of immune cells and/or reactive astrocytes, while the Day 10/Day 14 differences may indicate time-sensitive changes in these cells and their populations. With optimizations, including those of the irradiation time(s), microbeam pattern, dose, and perhaps concomitant treatments such as immunological intervention this method may ultimately reach clinical use.


Assuntos
Contusões/complicações , Membro Posterior/fisiopatologia , Membro Posterior/efeitos da radiação , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/radioterapia , Terapia por Raios X/métodos , Animais , Feminino , Método de Monte Carlo , Dosagem Radioterapêutica , Ratos , Ratos Long-Evans , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia , Síncrotrons , Fatores de Tempo , Terapia por Raios X/instrumentação
9.
Bioresour Technol ; 118: 243-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22705530

RESUMO

Mixtures of volatile reduced sulphur compounds (VRSCs) like hydrogen sulphide (H(2)S), methylmercaptan (MM), dimethyl sulphide (DMS) and dimethyl disulphide (DMDS) are found in gaseous emissions of several industrial activities creating nuisance in the surroundings. Hydrogen sulphide (H(2)S) decreases the removal efficiency of volatile reduced sulphur compounds (VRSCs) in biofilters but the kinetics of this effect is still unknown. Kinetic expressions that represent the rate of bio-oxidation of H(2)S, MM, DMS and DMDS are proposed. In order to observe and quantify this effect, equimolar mixtures of MM, DMS and DMDS were fed into a biotrickling filter inoculated with Thiobacillus thioparus at different H(2)S loads. Experimental results shown a good agreement with the simulations generated by the model considering the kinetic equations proposed. The estimated kinetic constants show that H(2)S and MM have a significant inhibitory effect on the bio-oxidation of DMS and DMDS, having the H(2)S the higher effect.


Assuntos
Reatores Biológicos , Filtração/instrumentação , Compostos de Enxofre/isolamento & purificação , Biodegradação Ambiental , Simulação por Computador , Dissulfetos/isolamento & purificação , Sulfeto de Hidrogênio/isolamento & purificação , Cinética , Oxirredução , Análise de Regressão , Compostos de Sulfidrila/isolamento & purificação , Sulfetos/isolamento & purificação , Thiobacillus/metabolismo , Volatilização
10.
Electron. j. biotechnol ; 15(3): 7-7, May 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-640551

RESUMO

Background: The behaviour of two biotrickling filters connected in serie (BTF) inoculated with Acidithiobacillus thiooxidans and Thiobacillus thioparus, biodegrading hydrogen sulphide (H2S) and dimethyl sulphide (DMS) simultaneously were studied. A model which considers gas to liquid mass transfer and biooxidation in the biofilm attached to the support is developed. Additionally, a fixed bed biotrickling filter where the microorganism is immobilized in a biofilm which degrades a mixture of H2S and DMS is implemented. Validation of the model was carried out using experimental data obtained at different H2S and DMS loads. Results: The inhibitory effect caused by the presence of H2S on the DMS is observed, which is evidenced by the decrease of the DMS removal efficiency from 80 to 27 percent, due to the preference that T. thioparus has by simple metabolism. H2S is not affected by the DMS, with removal efficiencies of 95 to 97 percent, but it decreases at high concentrations of the compound, due to the inhibition of metabolism by high H2S input loads. The model which describes the BFT fits successfully with the experimental results and it has a high sensitivity to inhibition parameters. Conclusion: It is shown that the microorganism has a high affinity for H2S, producing substrate inhibition when the concentration is high. The H2S is able to inhibit the DMS biooxidation, whereas the DMS does not affect the H2S biooxidation.


Assuntos
Filtração , Sulfeto de Hidrogênio , Modelos Teóricos , Sulfetos , Thiobacillus , Acidithiobacillus thiooxidans
11.
Biotechnol Lett ; 33(11): 2141-5, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21744275

RESUMO

Sulfolobus metallicus is a hyperthermophilic and chemolithoautotrophic archaeon that uses elemental sulfur as an energy source. Its ability to oxidize H(2)S was measured either in the presence or absence of elemental sulphur, showing its ability for using both as an energy source. A biotrickling filter was set up and a biofilm of S. metallicus was established over the support. The maximum removal capacity of the biotrickling filter reached at 55°C was 40 g S/m(3)h for input loads higher than 70 g S/m(3)h. Thus, S. metallicus can be used in a biofiltration system for the treatment of waste gas emissions at high temperatures contaminated with H(2)S.


Assuntos
Sulfeto de Hidrogênio/metabolismo , Sulfolobus/metabolismo , Biofilmes/crescimento & desenvolvimento , Filtração/métodos , Oxirredução , Sulfolobus/crescimento & desenvolvimento , Sulfolobus/fisiologia , Enxofre/metabolismo , Temperatura , Purificação da Água/métodos
12.
Electron. j. biotechnol ; 13(5): 11-12, Sept. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-591893

RESUMO

Reduced volatile sulphur compounds generate an impact on the environment, because of the bad smell and its low odour threshold. Compared with the existing physicochemical technologies for their elimination, biotrickling filters are an economically and environmentally sustainable alternative. Usually mixed cultures of microorganisms are used for inoculating biotrickling filters, in this case a pure culture of Thiobacillus thioparus is used for generating a biofilm, allowing to measure its capacity for the oxidation of four volatile reduced sulphur compounds: hydrogen sulphide, dimethyl sulphide, methyl mercaptan and dimethyl disulphide, using a residence time of 0.033 hrs. The viable cells of the biofilm were quantified by epifluorescence microscopy, staining the cells with ethidium bromide and acridine orange, polymerase chain reaction analysis in real time was used for testing the predominance of T. thiopharus in the biofilm. The microorganism was able to adhere and grow on the surface of rings made of polyethylene, with a viable population of 7•10(7) cell•ring-1, a 74 percent of total cells. The real time PCR showed a persistence of the population of T. thioparus for more than 300 days of operation, without being displaced by other microbial species. The maximum elimination capacities for each compound were 34.4; 21.8; 30.8 and 25.6 gS•m-3•h-1 for H2S, dimethylsulphide, dimethyldisulphide and methyl mercaptan, respectively. We conclude that it is possible to implement a biotrickling filter with the bacteria T. thioparus, which can oxidize volatile reduced sulphur compounds efficiently.


Assuntos
Filtração/métodos , Odorantes , Sulfetos/metabolismo , Thiobacillus/metabolismo , Biodegradação Ambiental , Biofilmes , Poluição Ambiental , Microscopia de Fluorescência , Oxirredução , Reação em Cadeia da Polimerase
13.
Med. leg. Costa Rica ; 24(1): 65-100, mar. 2007. ilus
Artigo em Espanhol | LILACS | ID: lil-585444

RESUMO

El presente trabajo de investigación sobre la revictimiación institucional pone de manifiesto la existencia de dicho fenómeno dentro del sistema judicial. Se analizan las causas de esta situación la cual aparenta no tener la debida cobertura del sistema ni la de los propios funcionarios que laboran en tal situación. Se hace una exposición de motivos que explica el fenómeno que incluye las políticas existentes, las estrategias de capacitación, difusión y consistencia. Además se estudia la existencia de la oficina deatención a la víctima del delito desde su iniciativa, la cual catapulta la figura de la víctima a un lugar hasta entonces negado, sin que su actuar trascienda al ámbito requerido por razones que se analizan. En las conclusiones se brindan recomendaciones pertinentes para quienes están sufriendo como víctimas por su labor.


This investigation about institutional revictimization demonstrates the existence of this phenomenon within the judicial system. The causes of this situation are analyzed, that seems not to have the appropriate coverage from the system nor from the employees of the institutions. An exposition of the different motives is done to explain the phenomenon that includes current policies, capacitating strategies, diffusion and consistency. Also the existence of the Attention to Victim of Crime Office is studied from its initiative, which catapults the victim figure to a previously denied place. As conclusions, some recommendations are brought for those who are suffering as victims.


Assuntos
Humanos , Vítimas de Crime , Medicina Legal , Legislação , Costa Rica
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