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1.
Opt Express ; 29(19): 30655-30665, 2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34614786

RESUMO

Snapshot multispectral imaging (MSI) has been widely employed in the rapid visual inspection by virtues of the non-invasive detection mode and short integration time. As the critical functional elements of snapshot MSI, narrowband, customizable, and pixel-level multispectral filter arrays (MSFAs) that are compatible with imaging sensors are difficult to be efficiently manufactured. Meanwhile, monolithically integrating MSFAs into snapshot multispectral imagers still remains challenging considering the strict alignment precision. Here, we propose a cost-efficient, wafer-level, and customized approach for fabricating transmissive MSFAs based on Fabry-Perot structures, both in the pixel-level and window-tiled configuration, by utilizing the conventional lithography combined with the deposition method. The MSFA chips own a total dimension covering the area of 4.8 mm × 3.6 mm with 4 × 4 bands, possessing the capability to maintain narrow line widths (∼25 nm) across the whole visible frequencies. After the compact integration with the imaging sensor, the MSFAs are validated to be effective in filtering and target identification. Our proposed fabrication method and imaging mode show great potentials to be an alternative to MSFAs production and MSI, by reducing both complexity and cost of manufacturing, while increasing flexibility and customization of imaging system.


Assuntos
Filtração/instrumentação , Nanoestruturas , Nanotecnologia/métodos , Óxido de Alumínio , Cor , Espectroscopia Dielétrica , Nanoestruturas/economia , Nanotecnologia/economia , Silício , Prata
2.
Anesthesiology ; 135(2): 246-257, 2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33984126

RESUMO

BACKGROUND: The SAME device (i-SEP, France) is an innovative filtration-based autotransfusion device able to salvage and wash both red blood cells and platelets. This study evaluated the device performances using human whole blood with the hypothesis that the device will be able to salvage platelets while achieving a erythrocyte yield of 80% and removal ratios of 90% for heparin and 80% for major plasma proteins without inducing signification activation of salvaged cells. METHODS: Thirty healthy human whole blood units (median volume, 478 ml) were diluted, heparinized, and processed by the device in two consecutive treatment cycles. Samples from the collection reservoir and the concentrated blood were analyzed. Complete blood count was performed to measure blood cell recovery rates. Flow cytometry evaluated the activation state and function of platelets and leukocytes. Heparin and plasma proteins were measured to assess washing performance. RESULTS: The global erythrocyte yield was 88.1% (84.1 to 91.1%; median [25th to 75th]) with posttreatment hematocrits of 48.9% (44.8 to 51.4%) and 51.4% (48.4 to 53.2%) for the first and second cycles, respectively. Ektacytometry did not show evidence of erythrocyte alteration. Platelet recovery was 36.8% (26.3 to 43.4%), with posttreatment counts of 88 × 109/l (73 to 101 × 109/l) and 115 × 109/l (95 to 135 × 109/l) for the first and second cycles, respectively. Recovered platelets showed a low basal P-selectin expression at 10.8% (8.1 to 15.2%) and a strong response to thrombin-activating peptide. Leukocyte yield was 93.0% (90.1 to 95.7%) with no activation or cell death. Global removal ratios were 98.3% (97.8 to 98.9%), 98.2% (96.9 to 98.8%), and 88.3% (86.6 to 90.7%) for heparin, albumin, and fibrinogen, respectively. The processing times were 4.4 min (4.2 to 4.6 min) and 4.4 min (4.2 to 4.7 min) for the first and second cycles, respectively. CONCLUSIONS: This study demonstrated the performance of the SAME device. Platelets and red blood cells were salvaged without significant impact on cell integrity and function. In the meantime, leukocytes were not activated, and the washing quality of the device prevented reinfusion of high concentrations of heparin and plasma proteins.


Assuntos
Transfusão de Sangue Autóloga , Transfusão de Plaquetas , Humanos , Transfusão de Sangue Autóloga/instrumentação , Transfusão de Sangue Autóloga/métodos , Desenho de Equipamento , Transfusão de Eritrócitos/instrumentação , Filtração/instrumentação , Filtração/métodos , Citometria de Fluxo , França , Transfusão de Plaquetas/instrumentação , Transfusão de Plaquetas/métodos
3.
Chemosphere ; 255: 126977, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32402891

RESUMO

The simultaneous removal of nitrate (15 mg N-NO3- L-1) and phosphate (12 mg P-PO43- L-1) from nutrient-polluted synthetic water was investigated in a recirculated pyrite-packed biofilter (RPPB) under hydraulic retention time (HRT) ranging from 2 to 11 h. HRT values ≥ 8 h resulted in nitrate and phosphate average removal efficiency (RE) higher than 90% and 70%, respectively. Decrease of HRT to 2 h significantly reduced the RE of both nitrogen and phosphorus. The RPPB showed high resiliency as reactor performance recovered immediately after HRT increase to 5 h. Solid-phase characterization of pyrite granules and backwashing material collected from the RPPB at the end of the study revealed that iron-phosphate, -hydroxide and -sulfate precipitated in the bioreactor. Thermodynamic modeling predicted the formation of S0 during the study. Residence time distribution tests showed semi-complete mixing hydrodynamic flow conditions in the RPPB. The RPPB can be considered an elegant and low-cost technology coupling biological nitrogen removal to the recovery of phosphorus, iron and sulfur via chemical precipitation.


Assuntos
Reatores Biológicos , Desnitrificação , Filtração/métodos , Ferro , Fósforo/isolamento & purificação , Sulfetos , Precipitação Química , Filtração/instrumentação , Ferro/isolamento & purificação , Nitrogênio/isolamento & purificação , Enxofre/química , Enxofre/isolamento & purificação
4.
PLoS One ; 15(4): e0231718, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32310994

RESUMO

Water sampling and filtration of environmental DNA (eDNA) analysis have been performed by several different methods, and each method may yield a different species composition or eDNA concentration. Here, we investigated the eDNA of seawater samples directly collected by SCUBA to compare two widely used filtration methods: open filtration with a glass filter (GF/F) and enclosed filtration (Sterivex). We referred to biomass based on visual observation data collected simultaneously to clarify the difference between organism groups. Water samples were collected at two points in the Sea of Japan in May, September and December 2018. The respective samples were filtered through GF/F and Sterivex for eDNA extraction. We quantified the eDNA concentration of five fish and two cnidarian species by quantitative polymerase chain reaction (qPCR) using species-specific primers/probe sets. A strong correlation of eDNA concentration was obtained between GF/F and Sterivex; the intercepts and slopes of the linear regression lines were slightly different in fish and jellyfish. The amount of eDNA detected using the GF/F filtration method was higher than that detected using Sterivex when the eDNA concentration was high; the opposite trend was observed when the eDNA concentration was relatively low. The concentration of eDNA correlated with visually estimated biomass; eDNA concentration per biomass in jellyfish was approximately 700 times greater than that in fish. We conclude that GF/F provides an advantage in collecting a large amount of eDNA, whereas Sterivex offers superior eDNA sensitivity. Both filtration methods are effective in estimating the spatiotemporal biomass size of target marine species.


Assuntos
Cnidários/genética , DNA Ambiental/genética , Filtração/instrumentação , Peixes/genética , Água do Mar/análise , Animais , DNA Ambiental/análise , DNA Ambiental/isolamento & purificação , Desenho de Equipamento , Cifozoários/genética
5.
Urology ; 135: 106-110, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31626857

RESUMO

OBJECTIVE: To examine long- and short-term outcomes using cell salvage with a commercially available leukocyte depletion filter following radical cystectomy in an oncologic population. MATERIALS AND METHODS: One hundred and fifty-seven patients, 87 of whom received a cell salvage transfusion, were retrospectively identified from chart review. Ninety-day outcomes as well as long-term mortality and cancer recurrence data were collected. Chi-square, Student's t, or Mann-Whitney U tests were used as appropriate. Multivariable regressions of survival were performed with a Cox proportional-hazards model. RESULTS: Those who received a cell salvage transfusion did not show any differences in rate of cancer recurrence (23%) vs those who did not receive a cell salvage transfusion (24%; P = .85). There were also no differences noted in mortality rates between the 2 populations (12% vs 17%; P = .36). Furthermore, no differences were noted in postoperative complication rates, length of hospital stay, 90-day culture positive infections or readmissions (P >.05). CONCLUSION: There are no significant differences in short-term or long-term patient outcomes between those who did and did not receive an intraoperative cell salvage transfusion. Cell salvage transfusions with a leukocyte depletion filter are safe and effective methods to reduce the need for allogeneic blood transfusions while controlling for the theoretical risk of metastatic spread.


Assuntos
Perda Sanguínea Cirúrgica/prevenção & controle , Transfusão de Sangue Autóloga/efeitos adversos , Cistectomia/efeitos adversos , Recidiva Local de Neoplasia/epidemiologia , Recuperação de Sangue Operatório/efeitos adversos , Neoplasias da Bexiga Urinária/cirurgia , Idoso , Idoso de 80 Anos ou mais , Transfusão de Sangue Autóloga/métodos , Feminino , Filtração/instrumentação , Seguimentos , Humanos , Tempo de Internação/estatística & dados numéricos , Procedimentos de Redução de Leucócitos/instrumentação , Leucócitos/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/etiologia , Inoculação de Neoplasia , Recuperação de Sangue Operatório/instrumentação , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento , Neoplasias da Bexiga Urinária/mortalidade , Neoplasias da Bexiga Urinária/patologia
6.
J Med Eng Technol ; 43(4): 248-254, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31478761

RESUMO

Postpartum haemorrhage (PPH), the leading cause of maternal mortality, is particularly problematic in low resource settings where access to safe blood supplies and definitive medical treatment is limited. We describe the continued development of an autotransfusion device designed to treat PPH by collection, filtration and infusion of maternal blood. Previous study has demonstrated that the device effectively moves blood through a filtration apparatus and removes up to 97% of aerobic bacteria but had poor anaerobic bacteria reduction. In this study, we investigate the filtration efficacy of the device using configurations comprised of three different leukocyte depletion filter designs: the Pall Leukoguard RS leukocyte reduction filter (PLRF), the Haemonetics BPF4™ (BPF4) leukocyte reduction filter, and the Haemonetics SCRC Leukotrap® (SCRC) filter. All configurations performed well with reductions ranging from 49 to 98%. Configurations containing 2 Haemonetics SCRC Leukotrap®filters (configuration 5 and 6) consistently reduced anaerobic bacteria by at least 73%. These results indicate that utilising a combination of SCRC and PLRF filters confers a high level of microbial filtration with improved removal of anaerobic organisms.


Assuntos
Transfusão de Sangue Autóloga/instrumentação , Filtração/instrumentação , Bactérias Anaeróbias , Feminino , Humanos , Leucócitos , Hemorragia Pós-Parto/terapia , Gravidez
7.
Food Chem ; 300: 125168, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31330368

RESUMO

This study reports a clear-cut relationship of the technological use of specific filter aids with highly variable vanadium levels in beer, wine, and fruit juices. First, the previously reported broad range of vanadium levels was confirmed in 68 commercial beverages by ICP-MS. Since cloudy apple juices exhibited significantly lower vanadium amounts than clear apple juices, filter aids used for clarification were analyzed and found to contain substantial and highly variable amounts of vanadium, particularly in all analyzed diatomite (38-368 mg vanadium per kg filter aid), but not in perlite products (<4 mg/kg). Subsequent pilot-scale precoat filtration experiments (170 L/batch) proved vanadium to be released from diatomite (Kieselguhr), increasing its levels from ca. 2.1-2.6 µg/kg unfiltered to 27-201 µg/kg filtered juice, depending on the use of diatomites high or low in vanadium. Thus, filter aid selection was shown to modulate the vanadium concentrations in clarified beverages.


Assuntos
Bebidas/análise , Filtração/instrumentação , Vanádio/análise , Óxido de Alumínio , Cerveja/análise , Terra de Diatomáceas/análise , Terra de Diatomáceas/química , Filtração/métodos , Contaminação de Alimentos/análise , Sucos de Frutas e Vegetais/análise , Malus , Dióxido de Silício , Vinho/análise
8.
J Radiol Prot ; 39(3): 749-765, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31018192

RESUMO

In air filter assay for radiological emergency response, radon (222Rn) and thoron (220Rn) progeny are known interferents to transuranic activity estimation. Previous work detailed a conservative, graded approach for TRU alpha activity estimation from air samples void of transuranic activity yet containing varying amounts of radon and thoron progeny. Validation of this method to produce rapid, conservative and defensible transuranic alpha activity estimates was accomplished through introduction of surrogate transuranic activity, 239Pu and 230Th check sources, along with the naturally occurring radioactive progeny from an environmental air filter. Following air collection, the filter was centre hole-punched with the transuranic check source placed underneath the filter during counting. With the surrogate transuranic activity introduced into the measurement, verification of the previously studied methodology for rapid transuranic activity estimation was determined with quantifiable conservative bias. 70 environmental filters with various levels of radon progeny and air sampling duration were collected; 35 examined with the 239Pu check source and 35 studied with the 230Th check source. To characterise the expected transuranic activity introduced to the counting experiment without the environmental interferents of radon and thoron progeny, 30 blank filters were counted using the described experimental setup with each of the respective surrogate sources. Following characterisation of the sources with blank filters, transuranic activity estimation comparison against the 70 environmental filters with natural background radioactive progeny interferents was accomplished. This work contributes to the comprehensive analysis of operational air samples by detailing validation results for a rapid and conservative transuranic alpha activity estimation methodology.


Assuntos
Poluentes Radioativos do Ar/análise , Plutônio/análise , Monitoramento de Radiação/métodos , Produtos de Decaimento de Radônio/análise , Urânio/análise , Filtração/instrumentação , North Carolina
9.
Anal Bioanal Chem ; 411(10): 1989-2000, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30798339

RESUMO

Ligand fishing is a widely used approach for screening active compounds from natural products. Recently, cell membrane (CM) as affinity ligand has been applied in ligand fishing, including cell membrane chromatography (CMC) and CM-coated magnetic bead. However, these methods possess many weaknesses, including complicated preparation processes and time-consuming operation. In this study, cheap and easily available cellulose filter paper (CFP) was selected as carrier of CM and used to fabricate a novel CM-coated CFP (CMCFP) for the first time. The type of CFP was optimized according to the amount of immobilized protein, and the immobilization of CM onto CFP by the insertion and self-fusion process was verified by confocal imaging. The CMCFP exhibited good selectivity and stability and was used for fishing potentially active compounds from extracts of Angelica dahurica. Three potentially active compounds, including bergapten, pabulenol, and imperatorin, were fished out and identified. The traditional Chinese medicine systems pharmacology database and analysis platform was used to build an active compound-target protein network, and accordingly, the gamma-aminobutyric acid receptor subunit alpha-1 (GABRA1) was deduced as potential target of CM for the active compounds of Angelica dahurica. Molecular docking was performed to evaluate the interaction between active compounds and GABRA1, and bergapten was speculated as a new potentially active compound. Compared with other methods, the fishing assay based on CMCFP was more effective, simpler, and cheaper.


Assuntos
Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Celulose/química , Descoberta de Drogas/instrumentação , Membrana Eritrocítica/metabolismo , Filtração/instrumentação , Angelica/química , Animais , Produtos Biológicos/química , Humanos , Ligantes , Simulação de Acoplamento Molecular , Papel , Coelhos , Receptores de GABA-A/metabolismo
10.
Chemosphere ; 223: 383-390, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30784745

RESUMO

Direct membrane filtration (DMF) is considered as a promising technology for municipal wastewater treatment. We utilized an innovative application of flat-sheet ceramic membranes (FSCM) for DMF for the rapid treatment of domestic sewage. Coagulation was applied before FSCM filtration to increase the pollutant removal and to mitigate membrane fouling. This coagulation-FSCM filtration can significantly reduce the pollutant load on the downstream treatment and concentrate organics and nutrients into sludge to facilitate resource recovery. Using polyaluminum chloride (PACl) based FSCM filtration, approximately 90.0% of the chemical oxygen demand (COD) and 99.0% of the phosphorus (P) were removed from the sewage influent and retained in the concentrated sludge, with less than 25.0 mg/L COD left in the effluent. Long-term operation of the PACl-based FSCM filtration stably maintained a high flux of 41.7 L/m2-h (LMH, or 1.0 m/d). The fouled membranes were cleaned chemically every 3-5 d, and the membrane permeability could almost be completely recovered using chemical backwash for only 10 min with a diluted acidic, alkaline, chlorine or H2O2 solution. The novel FSCM process will fundamentally advance wastewater treatment technology. It can be readily modularized and installed as simple add-on units to upgrade and retrofit existing wastewater treatment systems.


Assuntos
Cerâmica , Filtração/métodos , Membranas Artificiais , Esgotos/química , Incrustação Biológica/prevenção & controle , Análise da Demanda Biológica de Oxigênio , Recuperação e Remediação Ambiental/métodos , Filtração/instrumentação , Fósforo/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Purificação da Água/métodos
11.
Mater Sci Eng C Mater Biol Appl ; 97: 55-66, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30678941

RESUMO

The chronic kidney disease (CKD) patients are undergoing continuous ambulatory peritoneal dialysis (CAPD). However, there are some constraints, the frequent exchange of the dialysate and limitation of outside activity, associated with CAPD remain to be solved. In this study, we designed the wearable artificial kidney (WAK) system for peritoneal dialysis (PD) using urease-immobilized silk fibroin (SF) membrane and polymer-based spherical carbonaceous adsorbent (PSCA). We evaluated this kit's removal abilities of uremic toxins such as urea, creatinine, uric acid, phosphorus, and ß2-microglobulin from the dialysate of end-stage renal disease (ESRD) patients in vitro. The uremic toxins including urea, creatinine, uric acid, and phosphorus were removed about 99% by immobilized SF membrane and PSCA filter after 24 h treatment. However, only 50% of ß2-microglobulin was removed by this filtering system after 24 h treatment. In vivo study result shows that our filtering system has more uremic toxins removal efficiency than exchanged dialysate at every 6 h. We suggest that recirculating PD system using urease-immobilized SF membrane with PSCA could be more efficient than traditional dialysate exchange system for a WAK for PD.


Assuntos
Membranas Artificiais , Diálise Peritoneal Ambulatorial Contínua/instrumentação , Urease/química , Injúria Renal Aguda/terapia , Animais , Enzimas Imobilizadas/química , Desenho de Equipamento , Fibroínas/química , Filtração/instrumentação , Falência Renal Crônica/terapia , Masculino , Microscopia Eletrônica de Varredura , Diálise Peritoneal Ambulatorial Contínua/métodos , Fósforo/isolamento & purificação , Ratos Sprague-Dawley , Espectroscopia de Infravermelho com Transformada de Fourier , Toxinas Biológicas/química , Microglobulina beta-2/isolamento & purificação
12.
Biotechnol Prog ; 35(2): e2763, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30520568

RESUMO

Buffer exchange, desalting, and formulation of high-value biotherapeutics are currently performed using batch diafiltration (DF); however, this type of tangential flow filtration process may be difficult to implement as part of a fully continuous biomanufacturing process. The objective of this study was to explore the potential of using countercurrent dialysis for continuous protein formulation and buffer exchange. Experiments were performed using concentrated solutions of immunoglobuin G (IgG) with commercially available hollow fiber dialyzers having 1.5 and 1.8 m2 membrane surface area. More than 99.9% buffer exchange was obtained over a range of conditions, as determined from the removal of a model impurity (vitamin B12 ). The dialyzers were able to process more than 0.5 kg of IgG per day in an easily scalable low-cost process. In addition, buffer requirements were less than 0.02 L of buffer per gram IgG, which is several times less than that used in current batch DF processes. These results clearly demonstrate the potential of using low-cost hollow fiber dialyzers for buffer exchange and product formulation in continuous bioprocessing. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2763, 2019.


Assuntos
Terapia Biológica , Filtração , Imunoglobulina G/química , Soluções Tampão , Distribuição Contracorrente/instrumentação , Filtração/instrumentação , Porosidade , Propriedades de Superfície
13.
Water Res ; 143: 28-37, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-29940359

RESUMO

The objective of this project was to develop a novel phosphorus removal system using steel slag filters applicable in decentralized applications and to propose design criteria about maintenance needs. Slag exhaustion functions were measured on 2-3 mm, 3-5 mm, 5-10 mm and 16-23 mm slag. Three steel slag columns with particle size of 2-3 mm, 3-5 mm and 5-10 mm were fed with the effluent of an aerated lagoon during 589 days. A barrel reactor test was fed during 365 days with the effluent of an attached growth aerated biological reactor. The o-PO4 concentration at the effluent of the 2-3 mm and 3-5 mm columns and barrel reactor test was between 0.04 and 0.3 mg P/L. Particulate phosphorus, however, was removed by about 50%. The P-Hydroslag model implemented in PHREEQC was successfully calibrated with data from the column test, and validated with data from the barrel reactor test. The calibrated model was used to simulate long-term operation of a slag barrel reactor with two parallel streams of five replaceable steel slag barrels, with total hydraulic retention time of voids of 15 h. The system longevity was strongly influenced by the influent alkalinity. The simulated longevity was 7 years with an influent alkalinity of 50 mg CaCO3/L and 2 years with an influent of 210 mg CaCO3/L. The alkalinity of the steel slag filter influent was influenced by the type of aquifer supplying drinking water, the presence of nitrification activity and by the CO2 concentration in the enriched air of the upstream biological process. Simulated scenarios with partial barrel replacement (e. g. barrels 1 and 2 out of 5 replaced at frequency of 0.5, 1, 1.5, 2, 2.5, 3, 3.5 or 4 years) increased the system longevity up to 14 years while slightly increasing the number of barrels needed.


Assuntos
Filtração/instrumentação , Modelos Teóricos , Fósforo/isolamento & purificação , Eliminação de Resíduos Líquidos/instrumentação , Carbonato de Cálcio/química , Desenho de Equipamento , Fosfatos/química , Aço , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias
14.
J Occup Environ Hyg ; 15(8): 616-627, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29781773

RESUMO

The International Organization for Standardization (ISO) standard 16900-1:2014 specifies the use of sodium chloride (NaCl) and corn oil aerosols, and sulfur hexafluoride gas for measuring total inward leakage (TIL). However, a comparison of TIL between different agents is lacking. The objective of this study was to measure and compare TIL for respirators using corn oil and NaCl aerosols. TIL was measured with 10 subjects donning two models of filtering facepiece respirators (FFRs) including FFP1, N95, P100, and elastomeric half-mask respirators (ERs) in NaCl and corn oil aerosol test chambers, using continuous sampling methods. After fit testing with a PortaCount (TSI, Inc., St. Paul, MN) using the Occupational Safety and Health Administration (OSHA) protocol, five subjects were tested in the NaCl chamber first and then in the corn oil chamber, while other subjects tested in the reverse order. TIL was measured as a ratio of mass-based aerosol concentrations in-mask to the test chamber, while the subjects performed ISO 16900-1-defined exercises. The concentration of NaCl aerosol was measured using two flame photometers, and corn oil aerosol was measured with one light scattering photometer. The same instruments were used to measure filter penetration in both chambers using a Plexiglas setup. The size distribution of aerosols was determined using a scanning mobility particle sizer and charge was measured with an electrometer. Filter efficiency was measured using an 8130 Automated Filter Tester (TSI). Results showed the geometric mean TIL for corn oil aerosol for one model each of all respirator categories, except P100, were significantly (p < 0.05) greater than for NaCl aerosol. Filter penetration in the two test chambers showed a trend similar to TIL. The count median diameter was ∼82 nm for NaCl and ∼200 nm for corn oil aerosols. The net positive charge for NaCl aerosol was relatively larger. Both fit factor and filter efficiency influence TIL measurement. Overall, TIL determination with aerosols of different size distributions and charges using different methodologies may produce dissimilar results.


Assuntos
Óleo de Milho/análise , Dispositivos de Proteção Respiratória/normas , Cloreto de Sódio/análise , Aerossóis/análise , Face/anatomia & histologia , Filtração/instrumentação , Humanos , Exposição por Inalação , Tamanho da Partícula , Fotometria
15.
Food Res Int ; 108: 280-285, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29735059

RESUMO

The results found in the literature concerning the effect of consuming filter coffee brews on increasing the blood cholesterol levels due to the presence of diterpenes, are divergent. Thus the present research evaluated the diterpene (cafestol and kahweol) concentrations in filter coffee brews prepared with paper filters of different sizes, colors and origins (Brazil, Japan, The United States of America, Germany, France and the Netherlands), with and without micro perforations. This is the first study that reports the physical characteristics of paper filter and its importance to obtain filter coffee brew with low cafestol content. Thus, a sample of Catuai cultivar coffee with high cafestol content was roasted to a medium-light degree and used to prepare the brews in a 1:10 ratio (coffee powder to water). The diterpenes were extracted by direct saponification and quantified and identified by HPLC-DAD-MS/MS. The paper filters were physically characterized by measuring their grammage, and the fat permeation rate calculated in order to better understand the differences between the filters which allow one to obtain higher or lower diterpene contents. The cafestol and kahweol concentrations in the brews varied from 1.62 to 2.98 mg/L and from 0.73 to 1.96 mg/L, respectively. The highest cafestol and kahweol concentrations were obtained using paper filters with micro perforations, considering similar sized paper filters. The paper filters showed high fat permeability and grammages between 50.46 and 67.48 g/m2. The diterpene retention capacities of the filters produced in the different countries were similar. The results showed that the porosity of the paper filter and the particle size of the ground roasted coffee were determinant factors in obtaining filter coffee brews with lower cafestol contents.


Assuntos
Café/química , Culinária/instrumentação , Diterpenos/análise , Filtração/instrumentação , Papel , Cromatografia Líquida de Alta Pressão , Culinária/métodos , Desenho de Equipamento , Análise de Alimentos/métodos , Temperatura Alta , Tamanho da Partícula , Permeabilidade , Porosidade , Espectrometria de Massas em Tandem
16.
Water Sci Technol ; 77(7-8): 1899-1908, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29676747

RESUMO

In this study, an integrated aerobic membrane bioreactor (MBR)-nanofiltration (NF) system has been applied for advanced treatment of Opium processing wastewaters to comply with strict discharge limits. Aerobic MBR treatment was successfully applied to high strength industrial wastewater. In aerobic MBR treatment, a non-fouling unique slot aeration system was designed using computational fluid dynamics techniques. The MBR was used to separate treated effluent from dispersed and non-settleable biomass. Respirometric modeling using MBR sludge indicated that the biomass exhibited similar kinetic parameters to that of municipal activated sludge systems. Aerobic MBR/NF treatment reduced chemical oxygen demand (COD) from 32,000 down to 2,500 and 130 mg/L, respectively. The MBR system provided complete removal of total inorganic nitrogen; however, nearly 50 mgN/L organic nitrogen remained in the permeate. Post NF treatment after MBR permeate reduced nitrogen below 20 mgN/L, providing nearly total color removal. In addition, a 90% removal in the conductivity parameter was reached with an integrated MBR/NF system. Finally, post NF application to MBR permeate was found not to be practical at higher pH due to low flux (3-4 L/m2/hour) with low recovery rates (30-40%). As the permeate pH lowered to 5.5, 75% of NF recovery was achieved at a flux of 15 L/m2/hour.


Assuntos
Alcaloides/química , Reatores Biológicos , Filtração/instrumentação , Resíduos Industriais/análise , Eliminação de Resíduos Líquidos/métodos , Aerobiose , Análise da Demanda Biológica de Oxigênio , Membranas Artificiais , Nitrogênio/análise , Ópio/química , Eliminação de Resíduos Líquidos/instrumentação , Águas Residuárias/análise
17.
Artigo em Inglês | MEDLINE | ID: mdl-29553919

RESUMO

Experiments were carried out to test the capacity for a laboratory-scale biofilter operated at an elevated temperature level (∼50°C) to remove an air stream containing ß-caryophyllene, a naturally occurring sesquiterpene of environmental concern emitted from wood-related industrial facilities. A water jacket was used to maintain high temperatures in a laboratory-scale biofilter. Inocula, pollutant loading and nutrient supply rate effects were evaluated over 84 days of biofilter operation. The start-up process took over two months when citrus peels were used as inocula while a relatively short start-up period was achieved after introducing forest compost products. While using a sparged-gas bioreactor to cultivate an enrichment culture for 97 days, removal efficiencies in excess of 80% were observed after 18 days. At empty bed contact times of 50 s and at a pollutant loading rate of 3.05 mg C/L/hr, removal efficiency levels reached 90% and the elimination capacity level reached 2.29 mg C/L/hr, corresponding to an elimination capacity of 2.60 mg ß-caryophyllene/L/hr. Collectively, these results demonstrate that ß-caryophyllene can be successfully removed from contaminated air using a biofilter operated at a high temperature (∼50°C), expanding the temperature range within which biofilters are known to biodegrade sesquiterpenes.


Assuntos
Filtração/métodos , Gases/isolamento & purificação , Temperatura Alta , Sesquiterpenos/isolamento & purificação , Poluição do Ar/prevenção & controle , Biodegradação Ambiental , Reatores Biológicos , Citrus/química , Filtração/instrumentação , Gases/química , Sesquiterpenos Policíclicos , Sesquiterpenos/química , Temperatura , Madeira/química
18.
Health Phys ; 114(5): 479-485, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29505432

RESUMO

Dust loading on air sample filters is known to cause a loss of efficiency for direct counting of alpha activity on the filters, but the amount of dust loading and the correction factor needed to account for attenuated alpha particles is difficult to assess. In this paper, correction factors are developed by statistical analysis of a large database of air sample results for a uranium and plutonium processing facility at the Savannah River Site. As is typically the case, dust-loading data is not directly available, but sample volume is found to be a reasonable proxy measure; the amount of dust loading is inferred by a combination of the derived correction factors and a Monte Carlo model. The technique compares the distribution of activity ratios [beta/(beta + alpha)] by volume and applies a range of correction factors on the raw alpha count rate. The best-fit results with this method are compared with MCNP modeling of activity uniformly deposited in the dust and analytical laboratory results of digested filters. A linear fit is proposed to evenly-deposited alpha activity collected on filters with dust loading over a range of about 2 mg cm to 1,000 mg cm.


Assuntos
Contaminação Radioativa do Ar/análise , Partículas alfa , Poeira/análise , Monitoramento Ambiental/instrumentação , Filtração/instrumentação , Monitoramento de Radiação/instrumentação , Filtros de Ar , Plutônio/análise , Urânio/análise
19.
Chemosphere ; 196: 440-452, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29329081

RESUMO

To enhance the removal of natural organic matter (NOM) in ceramic (Ce) membrane filtration, an iron-aluminum binary oxide (FAO) was applied to the ceramic membrane surface as the adsorbent cake layer, and it was compared with heated aluminum oxide (HAO) for the evaluation of the control of NOM. Both the HAO and FAO adsorbent cake layers efficiently removed the NOM regardless of NOM's hydrophobic/hydrophilic characteristics, and the dissolved organic carbon (DOC) removal in NOM for FAO was 1-1.12 times greater than that for HAO, which means FAO was more efficient in the removal of DOC in NOM. FAO (0.03 µm), which is smaller in size than HAO (0.4 µm), had greater flux reduction than HAO. The flux reduction increased as the filtration proceeded because most of the organic foulants (colloid/particles and soluble NOM) were captured by the adsorbent cake layer, which caused fouling between the membrane surface and the adsorbent cake layer. However, no chemically irreversible fouling was observed on the Ce membrane at the end of the FAO adsorbent cake layer filtration. This means that a stable adsorbent cake layer by FAO formed on the Ce membrane, and that the reduced pure water flux of the Ce membrane, resulting from the NOM fouling, can easily be recovered through physicochemical cleaning.


Assuntos
Adsorção , Filtração/métodos , Membranas Artificiais , Óxidos/química , Purificação da Água/métodos , Óxido de Alumínio , Cerâmica , Coloides , Compostos Férricos , Filtração/instrumentação , Substâncias Húmicas , Interações Hidrofóbicas e Hidrofílicas , Soroalbumina Bovina/isolamento & purificação , Água
20.
G Ital Nefrol ; 34(5): 73-88, 2017 Sep 28.
Artigo em Italiano | MEDLINE | ID: mdl-28963829

RESUMO

Apheresis therapies play an important role in the treatment of many pathologies, both as first-line and rescue therapies after drug failure or drug toxicity and, furthermore, when it is important to reach a therapeutic goal in a short time. Apheresis devices have evolved at an astounding rate over the last decades. Therapeutic apheresis are usually part of a treatment plan, so, a patient-centered approach to select the most appropriate treatment for each patient, balancing personal preferences, medication interferences and technological availability can significantly influence the choice of the protocol to be used. But, if the wide diversity of apheresis treatments may offer a tailored-patient approach, it can also create concerns on the right decision about the most appropriate protocol. Therapeutic apheresis - whose purpose is to cure diseases due to abnormality of blood cells or to toxicity of plasma substances - and, productive apheresis - whose purpose is to produce autologous or allogeneic therapeutic hemocomponents - are widely known as plasma-treatments and cytapheresis. The elementary techniques in apheresis are well represented by three physical separation methods of blood components: 1. differential centrifugation; 2. membrane filtration; 3. adsorption of proteins or cells, from whole blood or from plasma already separated. Starting from these three processes, several apheretic techniques have been developed to ensure, in expert hands, excellent therapeutic efficacy together with a low profile of adverse events.


Assuntos
Remoção de Componentes Sanguíneos/métodos , Adsorção , Remoção de Componentes Sanguíneos/instrumentação , Remoção de Componentes Sanguíneos/tendências , Transfusão de Componentes Sanguíneos , Transfusão de Sangue Autóloga , Centrifugação , Filtração/instrumentação , Filtração/métodos , Humanos , Membranas Artificiais , Troca Plasmática/instrumentação , Troca Plasmática/métodos , Pressão , Desintoxicação por Sorção
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