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According to data from the Ministry of Employment and Labor in Korea, a significant portion of fatal accidents on construction sites occur due to collisions between construction workers and equipment, with many of these collisions being attributed to worker negligence. This study introduces a method for accurately localizing construction equipment and workers on-site, delineating areas prone to collisions as 'a danger area of a collision', and defining collision risk states. Utilizing advanced deep learning models which specialize in object detection, video footage obtained from strategically placed closed-circuit television (CCTV) cameras across the construction site is analyzed. The positions of each detected object are determined using transformation or homography matrices representing the conversion relationship between a sufficiently flat reference plane and image coordinates. Additionally, 'a danger area of a collision' is proposed for evaluating equipment collision risk based on the moving equipment's speed, and the validity of this area is verified. Through this, the paper presents a system designed to preemptively identify potential collision risks, particularly when workers are located within the 'danger area of a collision', thereby mitigating accident risks on construction sites.
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The unexpected failure of equipment such as pumps and fans in wastewater treatment plants can reduce wastewater treatment efficiency, leading to direct leakage of untreated wastewater into the environment. It is hence important to predict the possible consequences of equipment failure to minimize the leakage of harmful substances. This study examines the impacts of equipment shutdown on the performance and recovery time of a laboratory-scale anaerobic/anoxic/aerobic system with regard to reactor conditions and water quality. Two days after the air blowers are stopped, the concentrations of the soluble chemical oxygen demand, NH4-N, and PO4-P in the effluent of the settling tank increase to 122 mg/L, 23.8 mg/L, and 46.6 mg/L, respectively. These concentrations return to their initial values after 12, 24, and 48 h of restarting the air blowers. The concentrations of PO4-P and NO3-N in the effluent increase to 58 mg/L and 20 mg/L, respectively, about 24 h after stopping the return activated sludge and mixed liquor recirculation pumps, owing to the release of phosphates in the settling tank and inhibition of denitrification.
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Eliminação de Resíduos Líquidos , Purificação da Água , Reatores Biológicos , Águas Residuárias , Esgotos , NitrogênioRESUMO
In this work, liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for screening and confirmation of 64 illicit compounds in dietary supplements. The target compounds were illegally used pharmaceutical drugs, prohibited compounds, and not authorized ingredients for different therapeutics (sexual enhancement, weight loss, muscular strengthening, and relaxing products). The validation procedure was performed to evaluate selectivity, linearity, limit of detection (LOD), limit of quantification (LOQ), accuracy, and precision according to the Association of Official Analytical Chemists guidelines. The linearity was >0.98 in the range of 0.5-200 µg L-1. The LOQs were in the range 1-10 µg kg-1 for all target compounds. The accuracy (expressed as recovery) was 78.5-114%. The precision (expressed as the relative standard deviation) was below 9.15%. The developed method was applied for the determination of illicit compounds in dietary supplements collected from websites. As a result, the total detection rate was 13.5% (27 samples detected in 200 samples). The concentrations of detected samples ranged from 0.51 to 226 mg g-1. The proposed methodology is suitable for monitoring the adulteration of illicit compounds in dietary supplements.
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Suplementos Nutricionais/análise , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em TandemRESUMO
Defining the mechanisms underlying the control of mitochondrial fusion and fission is critical to understanding cellular adaptation to diverse physiological conditions. Here we demonstrate that hypoxia induces fission of mitochondrial membranes, dependent on availability of the mitochondrial scaffolding protein AKAP121. AKAP121 controls mitochondria dynamics through PKA-dependent inhibitory phosphorylation of Drp1 and PKA-independent inhibition of Drp1-Fis1 interaction. Reduced availability of AKAP121 by the ubiquitin ligase Siah2 relieves Drp1 inhibition by PKA and increases its interaction with Fis1, resulting in mitochondrial fission. High AKAP121 levels, seen in cells lacking Siah2, attenuate fission and reduce apoptosis of cardiomyocytes under simulated ischemia. Infarct size and degree of cell death were reduced in Siah2(-/-) mice subjected to myocardial infarction. Inhibition of Siah2 or Drp1 in hatching C. elegans reduces their life span. Through modulating Fis1/Drp1 complex availability, our studies identify Siah2 as a key regulator of hypoxia-induced mitochondrial fission and its physiological significance in ischemic injury and nematode life span.
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Proteínas de Ancoragem à Quinase A/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Dinaminas/metabolismo , Hipóxia/metabolismo , Mitocôndrias/fisiologia , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais/metabolismo , Isquemia Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Proteínas de Ancoragem à Quinase A/genética , Adaptação Fisiológica , Animais , Apoptose , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Linhagem Celular , Dinaminas/genética , Humanos , Hipóxia/genética , Hipóxia/patologia , Imuno-Histoquímica , Lentivirus , Longevidade , Fusão de Membrana , Camundongos , Camundongos Transgênicos , Proteínas Mitocondriais/genética , Isquemia Miocárdica/genética , Isquemia Miocárdica/patologia , Miócitos Cardíacos/citologia , Fosforilação , Transdução Genética , Ubiquitina-Proteína Ligases/genéticaRESUMO
The endoplasmic reticulum (ER) responds to changes in intracellular homeostasis through activation of the unfolded protein response (UPR). Yet, it is not known how UPR-signaling coordinates adaptation versus cell death. Previous studies suggested that signaling through PERK/ATF4 is required for cell death. We show that high levels of ER stress (i.e., ischemia-like conditions) induce transcription of the ubiquitin ligases Siah1/2 through the UPR transducers PERK/ATF4 and IRE1/sXBP1. In turn, Siah1/2 attenuates proline hydroxylation of ATF4, resulting in its stabilization, thereby augmenting ER stress output. Conversely, ATF4 activation is reduced upon Siah1/2 KD in cultured cells, which attenuates ER stress-induced cell death. Notably, Siah1a(+/-)::Siah2(-/-) mice subjected to neuronal ischemia exhibited smaller infarct volume and were protected from ischemia-induced death, compared with the wild type (WT) mice. In all, Siah1/2 constitutes an obligatory fine-tuning mechanism that predisposes cells to death under severe ER stress conditions.
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Isoenzimas/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Resposta a Proteínas não Dobradas , Animais , Células CHO , Células Cultivadas , Cricetinae , Cricetulus , Retículo Endoplasmático/metabolismo , Ativação Enzimática , Humanos , Camundongos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Estresse Fisiológico , Transcrição Gênica , Ubiquitina-Proteína Ligases/genéticaRESUMO
The relationship between financial constraints and depressive symptomatology among adults aged 50 and greater was examined. The mediating effect of perceived control over one's financial circumstances on this relationship was assessed. Ordinary least square hierarchical regression models were estimated using data from the Health and Retirement Study. As an aggregated measure, financial constraints were positively associated with depression in mid-age and late life, and this relationship was partially accounted for by the pathway of perceived control over one's financial circumstances. When disaggregated as a measure, financial constraints at the individual level had a significant effect on depression, while financial constraints at the family and public levels did not have a significant effect. When added to the model, perceived control over one's financial circumstances had a significant effect on depressive symptomatology, financial constraints remained significant at the individual level.
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Envelhecimento/psicologia , Depressão/epidemiologia , Controle Interno-Externo , Fatores Socioeconômicos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos/epidemiologiaRESUMO
Fouling control is an important consideration in the design and operation of membrane-based water treatment processes. It has been generally known that chemical cleaning is still the most common method to remove foultants and maintain the performance of reverse osmosis (RO) desalination. Regardless of the chemical membrane cleaning methods applied effectively, however, frequent chemical cleaning can shorten the membrane life. In addition, it also increases operating and maintenance costs due to the waste chemical disposal. As an alternative, osmotic backwashing can be applied to RO membranes by diluting the concentration polarization (CP) layer. In this study, the effects of osmotic backwashing were analysed under different total dissolved salts (TDSs) and backwashing conditions, and the parameters of the osmotic backwashing were evaluated. The results of the analysis based on the properties of the organic matters found in raw water showed that the cleaning efficiency in respect to the fouling by hydrophilic organic matters was the greatest. Osmotic backwashing was carried out by changing the TDS of the permeate. As a result, the backwashing volume decreased with time due to the CP of the permeate and the backwashing volume. The difference in the osmotic pressure between the raw water and the permeate (Delta pi) also decreased as time passed. It was confirmed that when the temperature of the effluent was high, both the cleaning efficiency and the backwashing volume, which inpours at the same time, increased. When the circulation flow of the effluent was high, both the cleaning efficiency and the backwashing volume increased.
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Osmose , Água do Mar , TemperaturaRESUMO
We examine how self-regulatory motivations of locomotion (initiation) and assessment (evaluation) are related to retirement wealth in middle-aged and older Americans. We test a hypothesis that high locomotion and some assessment levels predict high wealth levels. We use two national data sets: the 2008 Health and Retirement Study (N = 6,464) and the 2005 Midlife in the United States (N = 4,963). We found that a combination of high locomotion and moderate assessment motivation can maximize wealth accumulation. By creating this combination of locomotion and assessment motivations, policy interventions can be more effective in motivating wealth accumulation for retirement, such as a required annual review of retirement savings plans and understandable disclosure of the plans' costs.
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Envelhecimento/psicologia , Renda , Motivação , Aposentadoria , Controles Informais da Sociedade , Idoso , Coleta de Dados , Revelação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Política Pública , Estados UnidosRESUMO
Nuclear receptors (NRs) are implicated in the regulation of tumors and immune cells. We identify a tumor-intrinsic function of the orphan NR, NR2F6, regulating antitumor immunity. NR2F6 was selected from 48 candidate NRs based on an expression pattern in melanoma patient specimens (i.e., IFN-γ signature) associated with positive responses to immunotherapy and favorable patient outcomes. Correspondingly, genetic ablation of NR2F6 in a mouse melanoma model conferred a more effective response to PD-1 therapy. NR2F6 loss in B16F10 and YUMM1.7 melanoma cells attenuated tumor development in immune-competent but not -incompetent mice via the increased abundance of effector and progenitor-exhausted CD8+ T cells. Inhibition of NACC1 and FKBP10, identified as NR2F6 effectors, phenocopied NR2F6 loss. Inoculation of NR2F6 KO mice with NR2F6 KD melanoma cells further decreased tumor growth compared with NR2F6 WT mice. Tumor-intrinsic NR2F6 function complements its tumor-extrinsic role and justifies the development of effective anticancer therapies.
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Linfócitos T CD8-Positivos , Melanoma , Animais , Camundongos , Imunoterapia , Melanoma/genética , Proteínas Repressoras/metabolismoRESUMO
The RING finger E3 ubiquitin ligase Siah2 is implicated in control of diverse cellular biological events, including MAPK signaling and hypoxia. Here we demonstrate that Siah2 is subject to regulation by the deubiquitinating enzyme USP13. Overexpression of USP13 increases Siah2 stability by attenuating its autodegradation. Consequently, the ability of Siah2 to target its substrates prolyl hydroxylase 3 and Spry2 (Sprouty2) for ubiquitin-mediated proteasomal degradation is attenuated. Conversely, inhibition of USP13 expression with corresponding shRNA decreases the stability of both Siah2 and its substrate Spry2. Thus, USP13 limits Siah2 autodegradation and its ubiquitin ligase activity against its target substrates. Strikingly, the effect of USP13 on Siah2 is not mediated by its isopeptidase activity: mutations in its ubiquitin-binding sequences positioned within the ubiquitin-specific processing protease and ubiquitin-binding domains, but not within putative catalytic sites, abolish USP13 binding to and effect on Siah2 autodegradation and targeted ubiquitination. Notably, USP13 expression is attenuated in melanoma cells maintained under hypoxia, thereby relieving Siah2 inhibition and increasing its activity under low oxygen levels. Significantly, on melanoma tissue microarray, high nuclear expression of USP13 coincided with high nuclear expression of Siah2. Overall, this study identifies a new layer of Siah2 regulation mediated by USP13 binding to ubiquitinated Siah2 protein with a concomitant inhibitory effect on its activity under normoxia.
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Endopeptidases/metabolismo , Proteínas Nucleares/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina/metabolismo , Sítios de Ligação , Western Blotting , Linhagem Celular , Endopeptidases/genética , Estabilidade Enzimática , Humanos , Hidrólise , Imunoprecipitação , Mutagênese Sítio-Dirigida , Reação em Cadeia da Polimerase , Proteases Específicas de UbiquitinaRESUMO
Fouling mechanisms associated with membrane-based polysaccharide enrichment were determined using a dense ultrafiltration (UF) membrane. Dextran with different molecular weights (MWs) was used as a surrogate for polysaccharides. The influence of dextran MW on fouling mechanisms was quantified using the Hermia model. Flux data obtained with different dextran MWs and filtration cycles were plotted to quantify the more appropriate fouling mechanisms among complete pore blocking, standard pore blocking, intermediate pore blocking, and cake filtration. For 100,000 Da dextran, all four mechanisms contributed to the initial fouling. As the filtration progressed, the dominant fouling mechanism appeared to be cake filtration with a regression coefficient (R2) of approximately 0.9519. For 10,000 Da, the R2 value for cake filtration was about 0.8767 in the initial filtration. Then, the R2 value gradually decreased as the filtration progressed. For 6000 Da, the R2 values of the four mechanisms were very low in the initial filtration. However, as the filtration progressed, the R2 value for cake filtration reached 0.9057. These results clearly show that the fouling mechanism of dense UF membranes during polysaccharide enrichment can be quantified. In addition, it was confirmed that the dominant fouling mechanism can change with the size of the polysaccharide and the duration of filtration.
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Arginyl-tRNA-protein transferase 1 (ATE1) catalyses N-terminal protein arginylation, a post-translational modification implicated in cell migration, invasion and the cellular stress response. Herein, we report that ATE1 is overexpressed in NRAS-mutant melanomas, while it is downregulated in BRAF-mutant melanomas. ATE1 expression was higher in metastatic tumours, compared with primary tumours. Consistent with these findings, ATE1 depletion reduced melanoma cell viability, migration and colony formation. Reduced ATE1 expression also affected cell responses to mTOR and MEK inhibitors and to serum deprivation. Among putative ATE1 substrates is the tumour suppressor AXIN1, pointing to the possibility that ATE1 may fine-tune AXIN1 function in melanoma. Our findings highlight an unexpected role for ATE1 in melanoma cell aggressiveness and suggest that ATE1 constitutes a potential new therapeutic target.
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Aminoaciltransferases , Melanoma , Aminoaciltransferases/genética , Aminoaciltransferases/metabolismo , Movimento Celular , Proliferação de Células , Humanos , Melanoma/genética , Processamento de Proteína Pós-Traducional , RNA de Transferência/metabolismoRESUMO
Mutations in N-RAS and B-RAF, which commonly occur in melanomas, result in constitutive activation of the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated protein kinase (ERK) signaling. Active ERK increases expression and activity of the c-Jun transcription factor, linking ERK and Jun N-terminal kinase (JNK) cascades. Here, we show that c-Jun regulates transcription of phosphoinositide-dependent kinase 1 (PDK1) with a concomitant impact on Akt and protein kinase C (PKC) activity and related substrates. Inhibition of c-Jun reduces PDK1 expression and attenuates Akt and PKC activity, which can be restored by exogenous PDK1. c-Jun regulation of PDK1 in melanoma contributes to growth rate and the ability to form tumors in mice. Correspondingly, increased levels of c-Jun in melanoma cell lines coincide with up-regulation of PDK1 and phosphorylation of PKC and Akt. The identification of c-Jun as a transcriptional regulator of PDK1 expression highlights key mechanisms underlying c-Jun oncogenic activity, and provides new insight into the nature of up-regulated Akt and PKC in melanoma.
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Sistema de Sinalização das MAP Quinases , Melanoma/metabolismo , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Proto-Oncogênicas c-jun/metabolismo , Transcrição Gênica , Animais , Linhagem Celular Tumoral , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Camundongos , Camundongos Nus , Transplante de Neoplasias , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil , Transplante HeterólogoRESUMO
Physical or covalent adsorption of surface-active block or random copolymers consisting of anchoring units and functional units onto solid surfaces yields polymeric self-assembled monolayers (PSAMs) with designed chemical and morphological structures and functionalities. This tutorial review provides an overview of PSAMs derived from various types of copolymers. It also discusses design principles for PSAMs to tune interfacial and surface interactions of materials for potential applications.
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The objective of this study was to imitate undulatory motion, which is a commonly observed swimming mechanism of rays, using a soft morphing actuator. To achieve the undulatory motion, an artificial muscle built with shape memory alloy-based soft actuators was exploited to control the shape-changing behavior of a soft fin membrane. Artificial undulating fins were divided into two categories according to the method of generating the wave motion: single and multiple actuator-driven fins. For empirical research on the transformation and propulsion behavior of each fin type, the design and construction of bound propulsors were undertaken to mimic the structural and behavioral aspects of animals. To visualize the effect of undulatory motion on the swimming efficiency test of the fin beat frequency, a simplified soft undulating fin with a rectangular propulsor was constructed and tested. Additionally, dynamic modeling of the fin tip in wave-traveling was conducted for comparison and optimization. To optimize the thrust and propulsion efficiency of robot speed, the effects of the wave amplitude control and actuator sequence on the fin behavior were examined. An untethered robot was constructed according to the experimental results of the propulsors. Both exhibited exceptional swimming efficiency and maneuverability. The multiple actuator-driven ray robot exhibited a maximum swimming speed of 0.25 body lengths per second which is almost a similar swimming speed with previously reported robots. The developed robot achieved directional swimming (forward and backward) and turning (including rotation). Underwater exploration in an artificial environment was performed using the robot.
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Biomimética , Robótica , Animais , Fenômenos Biomecânicos , Locomoção , Ligas de Memória da Forma , NataçãoRESUMO
The optimal operating conditions of a combined dissolved air flotation (DAF)-microfiltration (MF) process to respond to changes in raw water quality were investigated by operating a pilot plant for two years. Without DAF pre-treatment (i.e., MF alone), MF operated stably with a transmembrane pressure (TMP) increase of 0.24 kPa/d when the turbidity of raw water was low and stable (max. 13.4 NTU). However, as the raw water quality deteriorated (max. 76.9 NTU), the rate of TMP increase reached 43.5 kPa/d. When DAF pre-treatment was applied (i.e., the combined DAF-MF process), the MF process operated somewhat stably; however, the rate of TMP increase was relatively high (i.e., 0.64 kPa/d). Residual coagulants and small flocs were not efficiently separated by the DAF process, exacerbating membrane fouling. Based on the particle count analysis of the DAF effluent, the DAF process was optimised based on the coagulant dose and hydraulic loading rate. After optimisation, the rate of TMP increase for the MF process stabilised at 0.17 kPa/d. This study demonstrates that the combined DAF-MF process responded well to substantial changes in raw water quality. In addition, it was suggested that the DAF process must be optimised to avoid excessive membrane fouling.
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Nitrosamines can be produced during the manufacture of rubber-type products such as pacifiers or the nipples of baby bottles. Humans can be exposed to the nitrosamines in these products when they are eluted into saliva. In this study, we compared the efficiency of electron impact ionization (EI), atmospheric pressure chemical ionization (APCI), and electrospray ionization (ESI) methods for the analysis of nine nitrosamines eluted into artificial saliva. In addition, nine nitrosamines eluted from 54 rubber-type products (rubber, thermoplastic elastomer, thermoplastic polyurethane, and polyurethane) marketed in Korea were monitored. Finally, non-carcinogenic and carcinogenic risk assessments of oral exposure to nine nitrosamines were performed based on the monitoring results. EI-GC-MS/MS performed the best for the simultaneous analysis of these nine nitrosamines with respect to overall linearity, trace analysis limit of detection (less than 1 µg), recovery (average 108.66 ± 9.32%), and precision (less than 6%), compared with liquid chromatography-tandem mass spectrometry (LC-MS/MS) (APCI and ESI) methods. Using the EI-GC-MS/MS method, these nine nitrosamines eluted into artificial saliva from 54 rubber-type products were monitored. Based on the monitoring data, risk assessment was performed by calculating the margin of exposure (MOE) for the respective nitrosamines detected. As a result, these nitrosamines were confirmed to be safe with regard to both non-carcinogenic and carcinogenic risks.
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PURPOSE: To evaluate the feasibility and effectiveness of preoperative localization of cystic lesions in the knee using ultrasound-guided indigo carmine injection. METHOD: Twenty-three cysts in the knee in 23 patients (M:F = 15:8, mean age, 42 years) were localized preoperatively by ultrasound-guided indigo carmine injection. These included 12 meniscal cysts, 7 popliteal cysts, and 4 ganglion cysts. To stain the lesions, 0.2-3 mL of indigo carmine was injected into the cyst using a 22-gauge spinal needle. After localization, the patient was immediately transferred to the operating room and surgery was performed. Intraoperative findings and arthroscopic images were reviewed. RESULT: All 23 cysts were stained successfully. Twenty cases were confirmed during arthroscopy and 3 cases were confirmed during excisional surgery. There was no significant bleeding/hematoma or anaphylactic reaction. Four patients felt pain during aspiration before indigo carmine injection. The lesions were stained blue and could be clearly identified by the surgeon and were removed arthroscopically or by open surgery. CONCLUSION: Preoperative localization of cystic lesions in the knee joint region using ultrasound-guided indigo carmine injection is a feasible technique and can be easily and safely be performed.
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Corantes , Cistos/diagnóstico por imagem , Índigo Carmim , Articulação do Joelho/diagnóstico por imagem , Cuidados Pré-Operatórios/métodos , Adulto , Cistos/cirurgia , Estudos de Viabilidade , Cistos Glanglionares/diagnóstico por imagem , Cistos Glanglionares/cirurgia , Humanos , Articulação do Joelho/cirurgia , Cisto Popliteal/diagnóstico por imagem , Cisto Popliteal/cirurgia , UltrassonografiaRESUMO
The application of magnetic ion-exchange resin (MIEX) during chemical coagulation was investigated for the removal of organic matters responsible for fouling in membrane processes. Two different coagulants were used-polyaluminium chloride (PAC1) and polyaluminum chloride silicate (PACS). The MIEX addition during coagulation with both PAC1 and PACS considerably enhanced removal of dissolved organic carbon. Coagulation with MIEX treatment substantially removed all portions of natural organic matter (NOM), while the MIEX treatment alone effectively removed the hydrophobic and transphilic portions of NOM. The enhanced NOM removal by PAC1 coagulation with the addition of MIEX had positive effects on membrane flux at moderate transmembrane pressure conditions. However, the almost identical flux patterns were reported in the experiments of coagulation with PACS and PACS with MIEX addition. The results of the specific cake resistances indicated that the MIEX addition substantially decreased the resistances. The larger size distributions of PAC1 with MIEX corresponded well with the flux improvement.
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Hidróxido de Alumínio/química , Silicatos de Alumínio/química , Resinas de Troca Iônica/química , Gerenciamento de Resíduos/métodos , Filtração , MagnetismoRESUMO
The recent influx of immigrants aged 65 and older in the United States triggers an increasing need to understand older immigrants' dental services use. This paper uses data (n = 9,617) from the 2004 and 2006 waves of the Health and Retirement Study to examine the dental services use of older Americans. In particular, this study focuses on differences in dental services use between immigrants and natives and potential contributing factors. Multivariate logistic regression analyses showed, contrary to expectation, that older immigrants were more likely to use dental services than older natives despite numerous barriers (odds ratio = 1.30 in 2004). The results in 2006 confirmed these findings. The results from 2004 and 2006 analyses showed dental insurance coverage, sex, and marital status were associated differently with dental services use for immigrants and natives. Implications for current oral health policies and future research of older Americans are discussed, as well as methods for meeting older immigrants' growing dental services needs.