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1.
J Bras Nefrol ; 42(2 suppl 1): 9-11, 2020 Aug 26.
Artigo em Inglês, Português | MEDLINE | ID: mdl-32877491

RESUMO

These recommendations were created after the publication of informative note 3/2020- CGGAP/DESF/SAPS/MS, of April 4, 2020, in which the Brazilian Ministry of Health recommended the use of a cloth mask by the population, in public places. Taking into account the necessary prioritization of the provision of Personal Protective Equipment (PPE) for patients with suspected or confirmed disease, as well as for healthcare professionals, the SBN is favorable concerning the wear of cloth masks by chronic kidney patients in dialysis, in public settings, except in the dialysis setting. The present recommendations have eleven items, related to this rationale, the procedures, indications, contraindications, as well as appropriate fabrics for the mask, and hygiene care to be adopted. These recommendations may change, at any time, in the light of new evidence.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Máscaras/normas , Pandemias/prevenção & controle , Equipamento de Proteção Individual/normas , Pneumonia Viral/prevenção & controle , Diálise Renal , Têxteis , Brasil , Infecções por Coronavirus/epidemiologia , Pessoal de Saúde , Humanos , Nefrologia/normas , Doenças Profissionais/prevenção & controle , Pneumonia Viral/epidemiologia , Roupa de Proteção/normas , Insuficiência Renal Crônica/terapia , Sociedades Médicas , Unidade Hospitalar de Urologia/normas
2.
J Environ Manage ; 273: 111114, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32738743

RESUMO

The study aimed at investigating the performance of anaerobic dynamic MBR (AnDMBR) for the treatment of synthetic textile wastewater. A laboratory scale anaerobic bioreactor was operated to test nylon mesh support materials with different pore sizes (20 µm, 53 µm and 100 µm). The performances of the AnDMBR were evaluated with a stimulated wastewater containing 1,000 mg.L-1 COD and 100 mg.L-1 dye (Remazol Brilliant Violet 5R). To develop an effective dynamic cake layer on the support material, different operational strategies, i.e. high flux, continuous and intermittently biogas recycle were studied for process optimization and increase the filtration performances. Initially, the bioreactor was operated under continuous biogas recycle. Under this operation strategy, the cake layer was not formed, then intermittent biogas recycle was applied to improve the development of dynamic layer. Effluent SS decreased below 20 mg-SS.L-1 for all the tested different pore sized supports after the development of the cake layer. Almost complete color (>99%) and high COD removal efficiencies (95-97%) were observed. For all the three supports, the bioreactor was operated at fluxes of 5-15 L.(m2.h)-1 (LMH), which was quite high compared to conventional AnMBRs equipped with micro/ultra-filtration membranes. In order to better understand the formation and its structure, detailed cake layer characterization analyses were conducted with scanning electron microscopy (SEM), SEM coupled Energy Dispersive X-ray Spectroscopy (EDS) and inductively coupled plasma-optical emission spectrometer (ICP). Provided the formation of the cake layer, the comparable flux and removal performances with AnMBRs for all three tested support materials were possible.


Assuntos
Membranas Artificiais , Águas Residuárias , Anaerobiose , Reatores Biológicos , Filtração , Têxteis
3.
J Environ Manage ; 272: 111082, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32854887

RESUMO

The remediation of a real textile wastewater aiming its reuse in the textile industry was carried out by integrating two processes: (i) a chemical or electrochemical advanced oxidation process (AOP or EAOP) based on Fenton's reaction for organics degradation, and (ii) a cation exchange process using marine macroalgae for removal of the iron acting in the Fenton's reaction based processes. Four AOPs/EAOPs at acidic pH 2.8 were tested: Fenton, photo-Fenton with ultraviolet A (UVA) radiation (PF/UVA), electro-Fenton (EF) and photoelectro-Fenton with UVA radiation (PEF/UVA). These processes provided very high color removals. After a running time of 45 min, the color removals were 68-95% for the Fenton process, 76-94% for the EF process, 80-98% for the PF/UVA process and 85-100% for the PEF/UVA process. In contrast, the mineralization was negligible for all the processes, indicating the generation/presence of persistent colorless compounds. The PF process was selected as first treatment stage due to its ability for color removal and related lower costs. A set of six marine macroalgae (Gracilaria caudata, Gracilaria cervicornis, Ascophyllum nodosum, Fucus spiralis, Laminaria hyperborea and Pelvetia canaliculata) were tested for iron uptake. Laminaria hyperborea showed the highest ion exchange capacity and affinity for iron species. Its application allowed the removal of all the iron acting in the PF process (3.4 mg/L). The textile wastewater resulting from the application of PF process followed by cation exchange with Laminaria hyperborea was successfully reused in scouring, bleaching and dyeing processes.


Assuntos
Águas Residuárias , Poluentes Químicos da Água/análise , Cátions , Peróxido de Hidrogênio , Oxirredução , Têxteis , Água
4.
Ann Ig ; 32(5): 472-520, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32744582

RESUMO

INTRODUCTION: The health emergency caused by the spread of SARS-COV-2 virus has required the adoption of passive measures against contagion, such as social distancing. The use of filtering masks, of the different types available on the market, such as surgical and facial filtering masks (FFP1, FFP2 and FFP3), is also recommended. OBJECTIVES: The aim of this paper, within the Italian and European regulatory reference framework, is to suggest a rational application of existing methodologies that enable to know and assess the features and/or make a face mask intended to be used by the community. In addition to this, the study aims to provide a correct regulatory framework and useful information for a correct use and disposal of face masks. Another purpose is the assessment of the hygienic, sanitary and regulatory aspects related to the use and disposal of face masks. METHODS: The analysis of filtering masks is based on the review of scientific literature, the state of art of technology and the filtering means/materials available. Reference is made to filtering mechanisms and devices, the testing methods, the technical, manufacturing and performance features, and to the Italian and European regulatory reference framework. Reference is also made to the hygienic, sanitary and regulatory aspects related to the use and disposal of face masks. RESULTS: Surgical masks or, alternatively, filtering masks with a filtration efficiency between 90% and 95% for 3-µm particles, are the most practicable choice with minor contraindications. The reusable type of mask is conceptually superior compared to single-use masks, but cleaning procedures to be followed are quite complex and not always described in a clear way. CONCLUSIONS: The definition of rigorous and repeatable tests on mask filtration capacity, breathability, wearability, duration of use, regeneration, as well as safe disposal methods, are the main way to provide users with correct selection and use criteria. The results must be disclosed and disseminated quickly.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/prevenção & controle , Filtração/instrumentação , Higiene/normas , Máscaras/normas , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Têxteis/normas , Desenho de Equipamento , Europa (Continente) , França , Humanos , Higiene/legislação & jurisprudência , Itália , Máscaras/classificação , Eliminação de Resíduos de Serviços de Saúde/legislação & jurisprudência , Eliminação de Resíduos de Serviços de Saúde/métodos , Eliminação de Resíduos de Serviços de Saúde/normas
5.
Ann Biomed Eng ; 48(9): 2281-2284, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32710248

RESUMO

The global COVID-19 pandemic disrupted supply chains across the world, resulting in a critical shortage of personal protective equipment (PPE) for frontline healthcare workers. To preserve PPE for healthcare providers treating COVID-19 positive patients and to reduce asymptomatic transmission, the Department of Bioengineering at the University of Colorado, Denver | Anschutz Medical Campus collaborated with National Jewish Health to design and test patterns for cloth face coverings. A public campaign to sew and donate the final pattern was launched and over 2500 face coverings have been donated as a result. Now that nearly three million cases of COVID-19 have been confirmed in the United States, many state and local governments are requiring cloth face coverings be worn in public. Here, we present the collaborative design and testing process, as well as the final pattern for non-patient facing hospital workers and community members alike.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Máscaras/provisão & distribução , Pandemias/prevenção & controle , Equipamento de Proteção Individual/provisão & distribução , Pneumonia Viral/prevenção & controle , Engenharia Biomédica , Colorado/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Pessoal de Saúde , Hospitais , Humanos , Colaboração Intersetorial , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Têxteis , Estados Unidos/epidemiologia , Design Universal
6.
G Ital Med Lav Ergon ; 42(2): 73-81, 2020 06.
Artigo em Italiano | MEDLINE | ID: mdl-32614536

RESUMO

SUMMARY: During COVID-19 pandemic crisis, Italian Government has approved Law Decree no. 18 of 17 march 2020, in which art. 15 allows enterprises to produce, import and commercialize surgical masks notwithstanding the current rules of product certification. It is just required that the interested enterprises send to the Italian National Institute of Health a selfcertification in which they declare the technical characteristics of the masks and that masks are produced according to the safety requirements. In this context, a technical-scientific unit was established at the University of Napoli Federico II to provide interested enterprises with state-of-the-art consultancy, testing and measurement services, adhering to rigorous scientific protocols. Characterization tests were carried out on 163 surgical masks and/or materials for their construction and they have enabled the identification of pre-screening criteria to simplify the procedure for evaluating surgical masks using methods for assessing the filtration efficiency of particles and aerosols. Based on experimental results, it has been observed that a filtration efficiency for particles with sizes larger that 650 nm (PFE>650) exceeding 35% might guarantees a bacterial filtration efficiency (BFE) higher than 95% while BFE values higher than 98% are obtained when the PFE>650 is larger than 40%. PFE measurement is extremely simpler with respect to BFE, the latter being time-consuming and requiring specific equipment and methods for its realization. Many tested materials have shown the capability to assure high filtration efficiencies but Spundonded-Meltblown-Spunbonded (SMS), that are layers of non-woven fabric with different weights of Meltblown, can simultaneously guarantee high particle filtration efficiencies with pressure drop values (breathability) in the limits to classify the surgical masks as Type II/IIR. In fact, the fabric products analyzed so far have not been able to simultaneously guarantee adequate BFE and breathability values. On the contrary, Spunbonds of adequate weights can virtually verify both requirements and accredit themselves as possible materials for the production of surgical masks, at least of Type I. Further studies are needed to verify the possibility of producing low-cost, reusable surgical masks that could meet the criteria of circular economy.


Assuntos
Infecções por Coronavirus/prevenção & controle , Filtração/instrumentação , Máscaras/normas , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Têxteis/normas , Desenho de Equipamento , Reutilização de Equipamento , Humanos , Itália , Teste de Materiais , Tamanho da Partícula
7.
Bioresour Technol ; 314: 123753, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32619804

RESUMO

Information on prospective metal remediation by Eudrilus eugeniae during vermicomposting of cotton textile sludge (CTS) is rather scarce. This investigation, therefore, evaluates the sanitization efficiency of this species in CTS and CTS + cow-dung (CD) based feedstocks against aerobic composting. Accordingly, reduction in Pb, Cd, Cr, and Zn concentrations was between 50 and 70% under vermicomposting. Budget equations substantiated that humic compound mediated chelation was the dominant route of metal removal, against nominal bioaccumulation by earthworms. Correlation statistics revealed that formation of humic compounds (humic acid, fulvic acid, and humin) greatly influenced the transition of toxic Cr6+ to benign Cr3+ during vermicomposting. Moreover, increase in total N content and P availability was significantly greater under vermicomposting than composting. Thus, E. eugeniae efficiently stabilized the feedstocks by reducing pH, Ca, S, and organic C and CTS + CD(2:1) was the most favorable feedstock for E. eugeniae vermicomposting in respect of metal detoxification and nutrient stabilization.


Assuntos
Oligoquetos , Animais , Bovinos , Cromo , Feminino , Substâncias Húmicas/análise , Metais , Estudos Prospectivos , Esgotos , Solo , Têxteis
8.
Bioresour Technol ; 314: 123728, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32665105

RESUMO

Industrialization increases use of dyes due to its high demand in paper, cosmetic, textile, leather and food industries. This in turn would increase wastewater generation from dye industrial activities. Various dyes and its structural compounds present in dye industrial wastewater have harmful effects on plants, animals and humans. Synthetic dyes are more resistant than natural dyes to physical and chemical methods for remediation which makes them more difficult to get decolorize. Microbial degradation has been researched and reviewed largely for quicker dye degradation. Genetically engineered microorganisms (GEMs) play important role in achieving complete dye degradation. This paper provides scientific and technical information about dyes & dye intermediates and biodegradation of azo dye. It also compiles information about factors affecting dye(s) biodegradation, role of genetically modified organisms (GMOs) in process of dye(s) degradation and perspectives in this field of research.


Assuntos
Compostos Azo , Corantes , Animais , Biodegradação Ambiental , Humanos , Indústria Têxtil , Têxteis , Águas Residuárias
9.
In Vivo ; 34(3 Suppl): 1637-1644, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: covidwho-541808

RESUMO

BACKGROUND: Sneezes produce many pathogen-containing micro-droplets with high velocities of 4.5-50.0 m/s. Face masks are believed to protect people from infection by blocking those droplets. However, current filtration efficiency tests can't evaluate masks under sneeze-like pressure. The goal of this study was to establish a method to evaluate the filtration efficiency of mask materials under extreme conditions. MATERIALS AND METHODS: Efficiency of surgical masks, gauze masks, gauze, cotton, silk, linen and tissue paper on blocking micro-droplet sized starch particles (average 8.2 µm) and latex microspheres (0.75 µm) with a velocity of 44.4 m/s created by centrifugation was qualitatively analyzed by using imaging-based analysis. RESULTS: The 4 layers of silk could block 93.8% of microspheres and 88.9% of starch particles, followed by the gauze mask (78.5% of microspheres and 90.4% of starch particles) and the 2 layers of cotton (74.6% of microspheres and 87.5-89.0% of particles). Other materials also blocked 53.2-66.5% of microspheres and 76.4%-87.9% of particles except the 8 layers of gauze which only blocked 36.7% of particles. The filtration efficiency was improved by the increased layers of materials. CONCLUSION: Centrifugation-based filtration efficiency test not only compensates shortcomings of current tests for masks, but also offers a simple way to explore new mask materials during pandemics. Common mask materials can potentially provide protection against respiratory droplet transmission.


Assuntos
Centrifugação/métodos , Controle de Infecções/instrumentação , Máscaras , Teste de Materiais/métodos , Espirro , Filtração , Humanos , Interações Hidrofóbicas e Hidrofílicas , Microesferas , Papel , Tamanho da Partícula , Material Particulado , Pressão , Eletricidade Estática , Têxteis
10.
PLoS One ; 15(6): e0228811, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32555686

RESUMO

Marine debris is currently a significant source of environmental and economic problems. Floating litter can be employed by marine organisms as a surface to attach to and use as spreading vector. Human activities are promoting the expansion of potentially harmful species into novel ecosystems, endangering autochthonous communities. In this project, more than 1,000 litter items were collected and classified from five beaches eastwards the port of Gijon, in Asturias, Spain. Next generation sequencing was employed to study biofouling communities attached to items of different materials. A dominance of DNA from Florideophyceae, Dinophyceae and Arthropoda was found, and four non-indigenous species (NIS) were identified. Results showed a clear preference of Florideophyceae and Bryozoa to attach on textile surfaces versus plastic ones. Considering that these taxa contain several highly invasive species described to date, these data emphasize the potential of textile marine debris as a vector for dispersal of NIS. Moreover, the closest beaches to the port contained a more similar biota profile than the farther ones, confirming that both plastic and textile marine litter can be vectors for species dispersal from ports.


Assuntos
DNA Ambiental/análise , Monitoramento Ambiental , Oceanos e Mares , Plásticos/química , Têxteis/análise , Poluentes Químicos da Água/química , Praias , Biofilmes , DNA Ambiental/genética , Sequenciamento de Nucleotídeos em Larga Escala
11.
PLoS One ; 15(6): e0234701, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579569

RESUMO

Despite the good mechanical properties of natural fibre composites, their use in load-bearing components is still limited, which may be due to lack of knowledge and confidence in calculating the performance of the composites by mechanical models. The present study is providing an experimental evaluation of stiffness predictions of multiaxial flax fibre composite by classical laminate theory (CLT). The experimental base is (i) multiaxial flax fibre composites fabricated with two types of biaxial non-crimp fabrics, having a nominal yarn orientation of ±45°, and (ii) uniaxial flax fibre composites fabricated with the same flax yarn as used in the fabrics. The fabricated composites are characterised by volumetric composition, yarn orientation and tensile properties. A fast and easy operational Fast Fibre Orientation (FFO) method is developed to determine the actual yarn orientation in fabrics and composites. It is demonstrated that the FFO method is a robust method, giving repeatable results for yarn orientations, and it can be used both on fabrics and composites. CLT predictions of stiffness of the multiaxial flax fibre composites are shown to be in good agreement with the measured stiffnesses of the composites in three testing directions (0°, 45°, and 90°). The use of the actual yarn orientations measured by the FFO method, instead of the nominal yarn orientations of ±45°, is shown to result in improved CLT predictions of stiffness with a mean deviation between predictions and measurements on 0.2 GPa. Altogether, it is demonstrated that stiffness of multiaxial flax fibre composites can be accurately predicted by CLT, without any fitting constants, based on independently determined stiffness parameters of the related uniaxial flax fibre composite, and based on measured yarn orientations in the flax fibre fabric.


Assuntos
Linho/fisiologia , Modelos Teóricos , Têxteis , Fenômenos Biomecânicos , Estresse Mecânico , Resistência à Tração
12.
PLoS One ; 15(6): e0233952, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32498075

RESUMO

This study aimed to produce cellulose-based conductive fabrics with electrical conductivity and flexibility. Bacterial cellulose (BC) and three chemical cellulose (CC), namely methyl cellulose (MC), hydroxypropyl cellulose (HPMC) and carboxymethyl cellulose (CMC) were in situ polymerized with aniline and the four conductive cellulose fabrics were compared and evaluated. Matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy analysis confirmed that three CC-PANI composites displayed longer and more stable polymerization pattern than BC-PANI because of the different polymerization method: bulk polymerization for BC-PANI and emulsion polymerization for CC-PANI, respectively. The electrical conductivity of BC-PANI and CC-PANI were ranging from 0.962 × 10-2 S/cm to 2.840 × 10-2 S/cm. MC-PANI showed the highest electrical conductivity among the four conductive cellulose fabrics. The flexibility and crease recovery results showed that MC-PANI had the highest flexibility compared to BC-PANI, HPMC-PANI, and CMC-PANI. These results have confirmed that the electrical conductivity and flexibility were influenced by the type of cellulose, and MC-PANI was found to have the best performance in the electrical conductivity and flexibility.


Assuntos
Carboximetilcelulose Sódica/química , Celulose/análogos & derivados , Metilcelulose/química , Polissacarídeos Bacterianos/química , Têxteis , Compostos de Anilina/química , Celulose/química , Elasticidade , Condutividade Elétrica , Nanocompostos/química , Polimerização , Têxteis/análise , Dispositivos Eletrônicos Vestíveis
13.
Yakugaku Zasshi ; 140(6): 809-818, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32475931

RESUMO

Standard analytical methods for the detection of dieldrin and 4,6-dichloro-7-(2,4,5-trichlorophenoxy)-2-trifluoromethylbenzimidazole (DTTB) in textiles, which are regulated by Japanese law ("Act on the Control of Household Products Containing Harmful Substances"), have been in place for more than 30 years. In this study, we developed an improved analytical method, based on GC-MS, that uses safe reagents and can simultaneously detect dieldrin and DTTB analytes. In the standard (existing) analytical method, dimethyl sulfate, which is a potential carcinogen, is used to derivatize DTTB. In the developed method, phenyltrimethylammonium hydroxide, as an alternative reagent, was used to derivatize DTTB in good results. Dieldrin and the derivatized DTTBs gave highly linear calibration curves when analyzed by GC-MS. Moreover, we found that both analytes are adequately extracted from textiles by refluxing in hydrochloric acid and methanol. Furthermore, we established a purification method using the Bond Elut PRS column that effectively removed interfering substances in woolen products. Finally, we developed an improved analysis method by combining the above-mentioned techniques; the developed method exhibited a recovery rate of 94-104% and a relative standard deviation of less than 7% for both analytes. In addition, the limits of quantitation (dieldrin: 1.3 µg/g, DTTB: 0.72 µg/g) were sufficiently lower than the Japanese regulatory value of 30 µg/g.


Assuntos
Benzimidazóis/análise , Dieldrin/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Têxteis/análise , Indicadores e Reagentes , Compostos de Amônio Quaternário
14.
ACS Nano ; 14(7): 9188-9200, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32584542

RESUMO

Filtration efficiency (FE), differential pressure (ΔP), quality factor (QF), and construction parameters were measured for 32 cloth materials (14 cotton, 1 wool, 9 synthetic, 4 synthetic blends, and 4 synthetic/cotton blends) used in cloth masks intended for protection from the SARS-CoV-2 virus (diameter 100 ± 10 nm). Seven polypropylene-based fiber filter materials were also measured including surgical masks and N95 respirators. Additional measurements were performed on both multilayered and mixed-material samples of natural, synthetic, or natural-synthetic blends to mimic cloth mask construction methods. Materials were microimaged and tested against size selected NaCl aerosol with particle mobility diameters between 50 and 825 nm. Three of the top five best performing samples were woven 100% cotton with high to moderate yarn counts, and the other two were woven synthetics of moderate yarn counts. In contrast to recently published studies, samples utilizing mixed materials did not exhibit a significant difference in the measured FE when compared to the product of the individual FE for the components. The FE and ΔP increased monotonically with the number of cloth layers for a lightweight flannel, suggesting that multilayered cloth masks may offer increased protection from nanometer-sized aerosol with a maximum FE dictated by breathability (i.e., ΔP).


Assuntos
Infecções por Coronavirus/prevenção & controle , Máscaras/normas , Pandemias/prevenção & controle , Equipamento de Proteção Individual/normas , Pneumonia Viral/prevenção & controle , Dispositivos de Proteção Respiratória/normas , Têxteis/normas , Aerossóis/química , Betacoronavirus/patogenicidade , Filtração , Humanos , Máscaras/virologia , Nanopartículas/química , Nanopartículas/virologia , Equipamento de Proteção Individual/virologia , Dispositivos de Proteção Respiratória/virologia , Têxteis/efeitos adversos , Têxteis/virologia
15.
Environ Sci Pollut Res Int ; 27(25): 32076-32087, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32506402

RESUMO

An ecofriendly and solar light-responsive graphene oxide wrapped zinc oxide nanohybrid has been synthesized hydrothermally using lemon and honey respectively as chelating and complexing agents. By tuning the reaction conditions, a heterostructure between GO and ZnO has been formed during synthesis. The photocatalytic activity of the synthesized nanohybrid was investigated by degradation of hazardous organic textile dye (methylene blue) as well as wastewater under natural solar light. The nanohybrid exhibited excellent photocatalytic activity towards degradation (~ 89%) of methylene blue (MeB). Furthermore, along with decolorization, 71% of mineralization was also achieved. Interestingly, the nanohybrid has been found to be reusable up to 4 cycles without significant loss of photocatalytic activity. Along with this, the physicochemical parameters of the wastewater generated from textile industry have been also monitored before and after exposure to nanohybrid. The results revealed significant reduction in chemical oxygen demand (COD) (96.33%), biochemical oxygen demand (BOD) (96.23%), and total dissolved solids (TDS) (20.85%), suggesting its potential applicability in textile wastewater treatment.


Assuntos
Nanocompostos , Óxido de Zinco , Catálise , Luz Solar , Têxteis
16.
Brain Behav Immun ; 88: 1-5, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32526447

RESUMO

'The Mask' has become a byword and a precious possession universally. Except for its use by the medical fraternity, answers to the common questions-whether it provides enough protection, which type is optimal for the general public and who really needs to don it, remain poorly understood. For a frontline healthcare worker, wearing mask is a necessity as an important person protection equipment, it is perhaps the most-powerful psychological symbol for the general public. Surprisingly, it even undermines all other recommended practices of infection control and breaking the transmission chain of Covid-19, like hand washing, personal hygiene and social distancing. 'The mask' has evolved with time and yet there is a need to further improve the design for safety, tolerability and comfort. In this review we present the journey of face mask, originating from the first masks aimed at stopping the bad smell to its industrial use to its all-important place in the medical field. Various types of face masks, their filtration efficiency, reusability and current recommendations for their use are presented.


Assuntos
Infecções por Coronavirus/prevenção & controle , Máscaras , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Dispositivos de Proteção Respiratória , Simbolismo , Betacoronavirus , Infecções por Coronavirus/transmissão , Reutilização de Equipamento , Guias como Assunto , Humanos , Controle de Infecções , Pneumonia Viral/transmissão , Têxteis
17.
Nano Lett ; 20(7): 5544-5552, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32484683

RESUMO

The COVID-19 pandemic is currently causing a severe disruption and shortage in the global supply chain of necessary personal protective equipment (e.g., N95 respirators). The U.S. CDC has recommended use of household cloth by the general public to make cloth face coverings as a method of source control. We evaluated the filtration properties of natural and synthetic materials using a modified procedure for N95 respirator approval. Common fabrics of cotton, polyester, nylon, and silk had filtration efficiency of 5-25%, polypropylene spunbond had filtration efficiency 6-10%, and paper-based products had filtration efficiency of 10-20%. An advantage of polypropylene spunbond is that it can be simply triboelectrically charged to enhance the filtration efficiency (from 6 to >10%) without any increase in pressure (stable overnight and in humid environments). Using the filtration quality factor, fabric microstructure, and charging ability, we are able to provide an assessment of suggested fabric materials for homemade facial coverings.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Máscaras , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Têxteis , Aerossóis , Microbiologia do Ar , Infecções por Coronavirus/transmissão , Eletricidade , Desenho de Equipamento , Filtração , Humanos , Máscaras/provisão & distribução , Microscopia Eletrônica de Varredura , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia , Tamanho da Partícula , Equipamento de Proteção Individual/provisão & distribução , Pneumonia Viral/transmissão
18.
Bioresour Technol ; 313: 123631, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32540694

RESUMO

A new oleaginous yeast consortium Y-BC-SH which stands for molecularly identified species Yarrowia sp., Barnettozyma californica and Sterigmatomyces halophilus was successfully constructed in this study. This multipurpose oleaginous yeast consortium was developed based on its higher ability to accumulate large amounts of lipids in the form of triacylglycerol, grow on xylose, produce lipase and xylanase and it could rapidly decolorize and degrade commonly-used textile reactive azo dyes. The specific enzyme activities of lipase, xylanase, xylan esterase, ß-xylosidase, CMCase, ß-glucosidase and cellobiohydrolase produced by Y-BC-SH were significantly higher than that of individual strains. As chemical oxygen demand reduction had occurred in the dye mixture solutions, it was evidence of their color removal and mineralization by Y-BC-SH. The significant induction of oxidoreductive enzymes by Y-BC-SH was probably due to the coordinated metabolic interactions of the individual strains. Phytotoxicity assay confirmed that metabolites generated after dye degradation by Y-BC-SH are non-toxic.


Assuntos
Corantes , Lipase , Compostos Azo , Biodegradação Ambiental , Têxteis
19.
Bioresour Technol ; 313: 123652, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32554152

RESUMO

Hydrolysis acidification (HA) is a classical method for synthetic textile wastewater treatment. However, the salinity effect on the functional mechanism of the microorganisms carrying out HA has rarely been researched. In the present study, the salinity effect on the dye removal efficiency was investigated, and the soluble microbial products (SMP), extracellular polymeric substances (EPS), and microbial community were analyzed at different salinities. The dye and COD removal rates in the HA reactor decreased with increasing salinity. Volatile fatty acids (VFAs) accumulated. The remarkable increases in SMP and EPS were found at high salinity, mainly because more polysaccharides were synthesized than protein. In addition, sequencing analysis showed that high salinity altered the microbial community structure, and Lactococcus, Raoultella and Enterococcus were the decolorizing bacteria at high salinity. This work will improve the understanding of the influence of salinity on the removal efficiency and microbial community during HA.


Assuntos
Salinidade , Águas Residuárias , Reatores Biológicos , Concentração de Íons de Hidrogênio , Hidrólise , Esgotos , Têxteis
20.
Chemosphere ; 257: 127199, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32480092

RESUMO

The ever-increasing use of domestic washing machine by urban population is playing a major role in synthetic microfibers (SMFs) pollution via entering the ecosystem. Although many of the sources of fragmented plastic pollution in oceanic environments have been well known, urban areas are playing a major contributor due to huge populations. Thousands of scientific investigations are now reporting the adverse effect of these micro pollutants on aquatic and terrestrial environment, food chain and human health. Microfiber particles along with washing machine grey waters are emitted into urban drainage adjoining the lakes and river which ultimately mix in ocean water and after emission these tiny particles dispersed though out the ocean water by currents due to their low density. Environmental pollution cause by domestic laundering processes of synthetic clothes has been reported as the major cause of primary microplastics in the marine system. While community awareness and improved education will be successful in making public conscious of this problem, there needs to be more research on global scale to mitigate the ecological consequences of microfiber pollution by urban habitats through environmental friendly approach. This paper focuses to improve the understanding of urban population influence on microfiber pollution, their ecological toxicity to aquatic organism and humans, detection and characterization techniques with an emphasis on future research for prevention and control of microfiber pollution.


Assuntos
Monitoramento Ambiental/métodos , Plásticos/toxicidade , Poluentes Químicos da Água/toxicidade , Organismos Aquáticos , Ecossistema , Poluentes Ambientais , Poluição Ambiental , Cadeia Alimentar , Humanos , Lagos , Oceanos e Mares , Rios , Têxteis , Água , Poluentes Químicos da Água/análise
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