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1.
Heliyon ; 10(11): e31720, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38845924

RESUMO

The primary drawback of concrete lies in its low tensile strength, prompting the development of various solutions to enhance this aspect. A notable approach is the utilization of Prestressed Reinforced Concrete (PRC) with tendons, aimed at bolstering its tensile strength. As the use of diverse tendon types in the PRC continues to surge, a review becomes imperative to delve into this evolution. Therefore, this study delved into the engineering characteristics, performance, and evolution of different tendon varieties, encompassing both steel and composite options. Despite certain drawbacks associated with employing composite materials such as Fiber Reinforced Polymer (FRP) tendons - such as heightened costs, limited availability of composite materials, and intricate manufacturing processes - there are distinct advantages and merits to incorporating FRP composite tendons in the realm of construction. In this respect, Carbon FRP tendons exhibited superior strength, comparable to their steel counterparts. Glass FRP tendons, lacking metallic components, possessed non-magnetic properties, rendering them resistant to corrosion. Additionally, Aramid FRP tendons boasted low flammability and exceptional resistance to elevated temperatures. Lastly, Basalt FRP tendons offered sustainability, rust resistance, and non-corrosiveness. The findings derived from this review study serve as a valuable resource for researchers seeking to advance the applications of steel tendons and FRP composite materials within the construction industry.

2.
J Affect Disord ; 354: 619-626, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38494140

RESUMO

BACKGROUND: Depression, migraine, insomnia, and fibromyalgia are reportedly comorbidities. Nevertheless, no study has evaluated the comorbidity of all four of these disorders. This study aimed to investigate the comorbidity of these four disorders. METHODS: Cross-sectional analyses were performed using data of the Circannual Change in Headache and Sleep study, an online nationwide population-based survey. Validated questionnaires were used to diagnose the disorders and measure quality of life. The change of clinical characteristics by addition of any comorbidity was analyzed using the Jonckheere-Terpstra trend test. RESULTS: The prevalence rates of depression, migraine, insomnia, and fibromyalgia were 7.2 %, 5.6 %, 13.3 %, and 5.8 %, respectively. Among the 3030 included participants, 494 (16.3 %), 164 (5.4 %), 40 (1.3 %), and 6 (0.2 %) had one, two, three, and four of these conditions, respectively. The number of headache days per 30 days (Jonckheere-Terpstra trend test, p = 0.011) and migraine-related disability (migraine disability assessment score, p = 0.021) increased with an increase in the number of comorbidities but not with the intensity of headache (visual analog scale, p = 0.225) among participants with migraine. The severity of insomnia (Insomnia Severity Index, p < 0.001) and fibromyalgia (fibromyalgia severity score, p = 0.002) increased with additional comorbidities; however, depression (Patient Health Questionnaire-9, p = 0.384) did not show such an increase. LIMITATIONS: The diagnoses of conditions were based on self-reported questionnaires. CONCLUSIONS: The findings confirmed significant comorbidity between depression, migraine, insomnia, and fibromyalgia. Health professionals should be aware of the probable comorbidity of depression, migraine, insomnia, and fibromyalgia when caring for individuals with any of these four disorders.


Assuntos
Fibromialgia , Transtornos de Enxaqueca , Distúrbios do Início e da Manutenção do Sono , Humanos , Fibromialgia/epidemiologia , Depressão/epidemiologia , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Estudos Transversais , Qualidade de Vida , Comorbidade , Transtornos de Enxaqueca/epidemiologia , Transtornos de Enxaqueca/diagnóstico , Cefaleia
3.
Mar Pollut Bull ; 197: 115791, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37992542

RESUMO

We examined long-term response (2008-2017) of the macrobenthos to the Hebei Spirit oil spill that occurred around the Taean coast, Korea, in December 2007. Oil concentrations were below the Korea/US environmental standards as of January 2008. Organic matter, chlorophyll-a, and zooplankton abundance dominated by Noctiluca scintillans were higher after the spill. Macrobenthic diversity recovered to pre-incident (2007) level in 2011. Biomass exceeded that level in 2011 and the increase prolonged for 5 years. Cross-correlation and regression analyses showed that chlorophyll-a at year t and zooplankton abundance at t-2 had a significant relationship with macrobenthic biomass at t (p < 0.05 for both), suggesting the transfer of increased organic matter (transformed from crude oil within the pelagic ecosystem) into the benthic ecosystem. Coastal wetlands around the incident area, vulnerable to oil pollution and slowly remobilizing accumulated oil, seemed to affect pelagic ecosystem processes and the unexpectedly increased and sustained biomass.


Assuntos
Poluição por Petróleo , Petróleo , Poluição por Petróleo/análise , Ecossistema , Estudos Longitudinais , Coreia (Geográfico) , Clorofila/análise , Clorofila A/análise , Petróleo/análise , República da Coreia
4.
Data Brief ; 50: 109570, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37767122

RESUMO

The dataset currently available comprises data on the removal rates of heavy metals (Ba, Se, Cr, Fe, Cd, As, and Co) through the incorporation of seashells and palm oil kernel shells into pervious concrete for stormwater treatment. Stormwater runoff was collected from commercial areas in Taman University, Skudai, Johor, Malaysia. The stormwater samples underwent filtration and were preserved in high-density polyethylene (HDPE) bottles at a temperature of 4 °C for use as incoming water. The outgoing water, referred to as effluent, was obtained from tests performed on pervious concrete samples after a curing period of 28 days. The pervious concrete mixes were created with a water-to-binder ratio (w/b ratio) of 32% and a sand ratio of 10%. Three different levels of palm oil kernel shell and seashell content were used as coarse aggregate replacements: 0%, 25%, and 50%. Two single-size group were considered for both palm oil kernel shell and seashell: (6.3-9.5 mm) and (4.75-6.3 mm). Heavy metal analyses were conducted on the influent and effluent using a PerkinElmer ELAN 6100 Series Inductively Coupled Plasma- Mass Spectrometer (ICP-MS). The available datasets consist of both raw and analyzed data.

5.
Environ Pollut ; 333: 122017, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37307864

RESUMO

Large amounts of microplastics are discharged into wastewater treatment plants (WWTPs), from where some of them are released into natural waterbodies on account of their not being fully eliminated by WWTPs. To investigate the behavior and emission of microplastics from WWTPs, we selected four WWTPs with different treatment technologies, including anaerobic-anoxic-aerobic (A2O), sequence batch reactor (SBR), media, and membrane bioreactor (MBR). The number of microplastics detected using Fourier transform infrared (FT-IR) spectroscopy ranged from 520 to 1820 particles/L in influent and from 0.56 to 2.34 particles/L in effluent. The microplastic removal efficiencies of four WWTPs were over 99%, indicating that the type of treatment technologies did not significantly affect the removal rate of microplastics. In the unit process for each WWTP, the major stages relating to microplastic removal were the secondary clarifier and tertiary treatment processes. Most microplastics detected were categorized as fragments and fibers, while other types were hardly detected. The size of more than 80% of microplastic particles detected in WWTPs ranged between 20 and 300 µm, indicating that they were significantly smaller than the size threshold defined for microplastics. Therefore, we used thermal extraction-desorption coupled with gas chromatography-mass spectroscopy (TED-GC-MS) to evaluate the microplastic mass content in all four WWTPs, and the results were compared with those of the FT-IR analysis. In this method, only four components, namely polyethylene, polypropylene, polystyrene, and polyethylene terephthalate, were analyzed because of the analysis limitation, and the total microplastic concentration represented the sum of four components concentrations. The influent and effluent microplastic concentrations estimated by TED-GC-MS ranged from not detectable to 160 µg/L and 0.04-1.07 µg/L, respectively, indicating a correlation coefficient of 0.861 (p < 0.05) between the TED-GC-MS and FT-IR results, when compared to the combined abundance of the four microplastic components by FT-IR analysis.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Microplásticos , Plásticos/análise , Águas Residuárias , Espectroscopia de Infravermelho com Transformada de Fourier , Análise de Fourier , Cromatografia Gasosa-Espectrometria de Massas , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Eliminação de Resíduos Líquidos
6.
BMC Oral Health ; 22(1): 571, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36476146

RESUMO

BACKGROUND: Assessing the time required for tooth extraction is the most important factor to consider before surgeries. The purpose of this study was to create a practical predictive model for assessing the time to extract the mandibular third molar tooth using deep learning. The accuracy of the model was evaluated by comparing the extraction time predicted by deep learning with the actual time required for extraction. METHODS: A total of 724 panoramic X-ray images and clinical data were used for artificial intelligence (AI) prediction of extraction time. Clinical data such as age, sex, maximum mouth opening, body weight, height, the time from the start of incision to the start of suture, and surgeon's experience were recorded. Data augmentation and weight balancing were used to improve learning abilities of AI models. Extraction time predicted by the concatenated AI model was compared with the actual extraction time. RESULTS: The final combined model (CNN + MLP) model achieved an R value of 0.8315, an R-squared value of 0.6839, a p-value of less than 0.0001, and a mean absolute error (MAE) of 2.95 min with the test dataset. CONCLUSIONS: Our proposed model for predicting time to extract the mandibular third molar tooth performs well with a high accuracy in clinical practice.


Assuntos
Inteligência Artificial , Aprendizado Profundo , Humanos , Dente Serotino/diagnóstico por imagem , Dente Serotino/cirurgia , Extração Dentária , Duração da Cirurgia
7.
Bioact Mater ; 18: 433-445, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35415304

RESUMO

All-in-one treatments represent a paradigm shift in future medicine. For example, inflammatory bowel disease (IBD) is mainly diagnosed by endoscopy, which could be applied for not only on-site monitoring but also the intestinal lesion-targeted spray of injectable hydrogels. Furthermore, molecular conjugation to the hydrogels would program both lesion-specific adhesion and drug-free therapy. This study validated this concept of all-in-one treatment by first utilizing a well-known injectable hydrogel that underwent efficient solution-to-gel transition and nanomicelle formation as a translatable component. These properties enabled spraying of the hydrogel onto the intestinal walls during endoscopy. Next, peptide conjugation to the hydrogel guided endoscopic monitoring of IBD progress upon adhesive gelation with subsequent moisturization of inflammatory lesions, specifically by nanomicelles. The peptide was designed to mimic the major component that mediates intestinal interaction with Bacillus subtilis flagellin during IBD initiation. Hence, the peptide-guided efficient adhesion of the hydrogel nanomicelles onto Toll-like receptor 5 (TLR5) as the main target of flagellin binding and Notch-1. The peptide binding potently suppressed inflammatory signaling without drug loading, where TLR5 and Notch-1 operated collaboratively through downstream actions of tumor necrosis factor-alpha. The results were produced using a human colorectal cell line, clinical IBD patient cells, gut-on-a-chip, a mouse IBD model, and pig experiments to validate the translational utility.

8.
Nat Commun ; 12(1): 5410, 2021 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-34518530

RESUMO

Photoacoustic (PA) imaging is a functional and molecular imaging technique capable of high sensitivity and spatiotemporal resolution at depth. Widespread use of PA imaging, however, is limited by currently available contrast agents, which either lack PA-signal-generation ability for deep imaging or their absorbance spectra overlap with hemoglobin, reducing sensitivity. Here we report on a PA contrast agent based on targeted liposomes loaded with J-aggregated indocyanine green (ICG) dye (i.e., PAtrace) that we synthesized, bioconjugated, and characterized to addresses these limitations. We then validated PAtrace in phantom, in vitro, and in vivo PA imaging environments for both spectral unmixing accuracy and targeting efficacy in a folate receptor alpha-positive ovarian cancer model. These study results show that PAtrace concurrently provides significantly improved contrast-agent quantification/sensitivity and SO2 estimation accuracy compared to monomeric ICG. PAtrace's performance attributes and composition of FDA-approved components make it a promising agent for future clinical molecular PA imaging.


Assuntos
Meios de Contraste/química , Verde de Indocianina/química , Lipossomos/química , Imagem Molecular/métodos , Nanopartículas/química , Técnicas Fotoacústicas/métodos , Células 3T3 , Animais , Linhagem Celular Tumoral , Células Cultivadas , Feminino , Receptor 1 de Folato/química , Receptor 1 de Folato/metabolismo , Humanos , Camundongos , Camundongos Nus , Microscopia Eletrônica de Transmissão/métodos , Nanopartículas/ultraestrutura , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/metabolismo , Imagens de Fantasmas , Transplante Heterólogo
9.
Small ; 16(16): e2000012, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32239653

RESUMO

Atherosclerosis development leads to irreversible cascades, highlighting the unmet need for improved methods of early diagnosis and prevention. Disturbed flow formation is one of the earliest atherogenic events, resulting in increased endothelial permeability and subsequent monocyte recruitment. Here, a mesenchymal stem cell (MSC)-derived nanovesicle (NV) that can target disturbed flow sites with the peptide GSPREYTSYMPH (PREY) (PMSC-NVs) is presented which is selected through phage display screening of a hundred million peptides. The PMSC-NVs are effectively produced from human MSCs (hMSCs) using plasmid DNA designed to functionalize the cell membrane with PREY. The potent anti-inflammatory and pro-endothelial recovery effects are confirmed, similar to those of hMSCs, employing mouse and porcine partial carotid artery ligation models as well as a microfluidic disturbed flow model with human carotid artery-derived endothelial cells. This nanoscale platform is expected to contribute to the development of new theragnostic strategies for preventing the progression of atherosclerosis.


Assuntos
Aterosclerose/terapia , Células-Tronco Mesenquimais , Nanopartículas , Animais , Artérias Carótidas , Células Endoteliais , Humanos , Ligadura , Camundongos , Suínos
10.
ACS Omega ; 4(14): 16103-16110, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31592478

RESUMO

Contributing to recent lignin valorization efforts, this study uses an integrative approach to explore the effects of fractionation parameters on lignin characteristics. The following reaction parameters are explored: water content of the water-organic solvent mixture, reaction temperature, and sulfuric acid content. Ethylene glycol (EG) was selected as the fractionation solvent because of its promising lignin solubility and extractability. This study takes a novel approach in conducting EG-assisted biomass fractionation; instead of removing lignin from the biomass, lignin was extracted and characterized. Lignin characteristics involving recovery and linkages were analyzed. A maximum of 27 wt % lignin recovery was achieved at a low water content (25%) and high reaction temperature (180 °C) in the presence of sulfuric acid (1 wt %). From NMR analysis, aryl-ether linkages, which are important to preserve for lignin valorization, were decomposed as a result of relatively high temperature and the presence of sulfuric acid. Statistical analysis showed that all individual parameters and their interactions had significant effects on lignin recovery. Computational analysis revealed that hydrogen bonding between the EG and lignin macromolecules greatly decreased with an increasing amount of water.

11.
ACS Omega ; 4(3): 6050-6058, 2019 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-31459753

RESUMO

Multistep activation of a Canadian oilsands petroleum coke that yields an acidified mesoporous carbon catalyst is reported. Microporous-activated carbon (APC; ∼2000 m2/g), obtained by thermochemical activation of petroleum coke using KOH, was impregnated with ammonium heptamolybdate and activated by carbothermal hydrogen reduction (CHR). The resulting Mo2C, supported on high-mesopore volume (V meso ∼0.4 cm3/g) carbon, yields the desired mesoporous carbon catalyst (V meso ∼0.7 cm3/g) following acid washing. The effect of CHR temperature and the benefit of Mo2C loading on mesopore development is reported, and pore development models are discussed. The mesoporous carbons are active for the esterification of acetic acid and 1-butanol at 77 °C, and the butanol conversion correlates with the catalyst acidity, as measured by NH3-TPD.

12.
PLoS One ; 14(2): e0211480, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30794560

RESUMO

BACKGROUND/PURPOSE: Few studies have examined the risk factors for gallbladder (GB) disease in young adults. This study aimed to evaluate risk factors for GB disease in young adults based on big data in Korea. METHODS: All participants underwent routine checkup at the Korea Medical Institute from June 2014 to May 2015. After excluding 677 individuals with missing information in records, 724,114 individuals (435,635 men, 288,479 women) were finally included. The definition of abnormal GB finding included stones, sludge, polyps, and adenomyomatosis detected using ultrasonography. All statistical analyses were performed using SAS software version 9.2. RESULTS: Overall, 27,130 (17.5%) individuals were diagnosed as having abnormal GB finding in the young age group (N = 154,463, aged 20-39 years). In men, significant differences in low-density lipoprotein (LDL) and cholesterol levels were observed between the abnormal GB finding group and normal GB group (p < 0.05). In women, a significant difference in smoking history was noted between the abnormal GB finding group and normal GB group (p < 0.05). The prevalence rate of GB stones was 1.9% (27,979/154,463) in the young age group. High body mass index (BMI), large thigh circumference, and low high-density lipoprotein (HDL) level in women and low HDL level in men were independent risk factors for the presence of GB stones (p < 0.05). CONCLUSION: In this study, obesity-related factors (BMI, waist size, thigh circumference, and cholesterol, LDL, and HDL levels) correlated with GB disease in the young generation of Korea.


Assuntos
Big Data , Doenças da Vesícula Biliar/epidemiologia , Obesidade/complicações , Adulto , Índice de Massa Corporal , Colesterol/sangue , Feminino , Doenças da Vesícula Biliar/complicações , Cálculos Biliares/complicações , Cálculos Biliares/epidemiologia , Humanos , Masculino , Síndrome Metabólica/complicações , Síndrome Metabólica/epidemiologia , Obesidade/epidemiologia , Prevalência , República da Coreia/epidemiologia , Fatores de Risco , Triglicerídeos/sangue , Circunferência da Cintura
13.
Front Plant Sci ; 10: 1774, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32082342

RESUMO

The complex and heterogeneous polyphenolic structure of lignin confers recalcitrance to plant cell walls and challenges biomass processing for agroindustrial applications. Recently, significant efforts have been made to alter lignin composition to overcome its inherent intractability. In this work, to overcome technical difficulties related to biomass recalcitrance, we report an integrated strategy combining biomass genetic engineering with a pretreatment using a bio-derived deep eutectic solvent (DES). In particular, we employed biomass from an Arabidopsis line that expressed a bacterial hydroxycinnamoyl-CoA hydratase-lyase (HCHL) in lignifying tissues, which results in the accumulation of unusual C6C1 lignin monomers and a slight decrease in lignin molecular weight. The transgenic biomass was pretreated with renewable DES that can be synthesized from lignin-derived phenols. Biomass from the HCHL plant line containing C6C1 monomers showed increased pretreatment efficiency and released more fermentable sugars up to 34% compared to WT biomass. The enhanced biomass saccharification of the HCHL line is likely due to a reduction of lignin recalcitrance caused by the overproduction of C6C1 aromatics that act as degree of polymerization (DP) reducers and higher chemical reactivity of lignin structures with such C6C1 aromatics. Overall, our findings demonstrate that strategic plant genetic engineering, along with renewable DES pretreatment, could enable the development of sustainable biorefinery.

14.
Nano Converg ; 5(1): 3, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29399435

RESUMO

A key design consideration in developing contrast agents is obtaining distinct, multiple signal changes in diseased tissue. Plasmonic gold nanoparticles (Au NPs) have been developed as contrast agents due to their strong surface plasmon resonance (SPR). This study aims to demonstrate that stimuli-responsive plasmonic Au nanoclusters (Au NCs) can be used as a contrast agent for optical coherence tomography (OCT) in detecting early-stage cancer. Au NPs were clustered via acid-cleavable linkers to synthesize Au NCs that disassemble under mildly acidic conditions into individual Au NPs, simultaneously diminishing SPR effect (quantified by scattering intensity) and increasing Brownian motion (quantified by Doppler variance). The acid-triggered morphological and accompanying optico-physical property changes of the acid-disassembling Au NCs were confirmed by TEM, DLS, UV/Vis, and OCT. Stimuli-responsive Au NCs were applied in a hamster check pouch model carrying early-stage squamous carcinoma tissue. The tissue was visualized by OCT imaging, which showed reduced scattering intensity and increased Doppler variance in the dysplastic tissue. This study demonstrates the promise of diagnosing early-stage cancer using molecularly programmable, inorganic nanomaterial-based contrast agents that are capable of generating multiple, stimuli-triggered diagnostic signals in early-stage cancer.

15.
ACS Appl Mater Interfaces ; 9(27): 22994-23006, 2017 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-28621931

RESUMO

Human bone marrow derived mesenchymal stem cells (hMSCs) hold great promise for regenerative medicine due to their multipotent differentiation capacity and immunomodulatory capabilities. Substantial research has elucidated mechanisms by which extracellular cues regulate hMSC fate decisions, but considerably less work has addressed how material properties can be leveraged to maintain undifferentiated stem cells. Here, we show that synthetic culture substrates designed to exhibit moderate cell-repellency promote high stemness and low oxidative stress-two indicators of naïve, healthy stem cells-in commercial and patient-derived hMSCs. Furthermore, the material-mediated effect on cell behavior can be tuned by altering the molar percentage (mol %) and/or chain length of poly(ethylene glycol) (PEG), the repellant block linked to hydrophobic poly(ε-caprolactone) (PCL) in the copolymer backbone. Nano- and angstrom-scale characterization of the cell-material interface reveals that PEG interrupts the adhesive PCL domains in a chain-length-dependent manner; this prevents hMSCs from forming mature focal adhesions and subsequently promotes cell-cell adhesions that require connexin-43. This study is the first to demonstrate that intrinsic properties of synthetic materials can be tuned to regulate the stemness and redox capacity of hMSCs and provides new insight for designing highly scalable, programmable culture platforms for clinical translation.


Assuntos
Células-Tronco Mesenquimais , Diferenciação Celular , Humanos , Oxirredução , Polietilenoglicóis , Medicina Regenerativa
16.
Nanomedicine (Lond) ; 11(12): 1571-8, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27175480

RESUMO

BACKGROUND: Nanocapsules can efficiently encapsulate therapeutic cargo for anticancer drug delivery. However, the controlled release of the payload remains a challenge for effective drug delivery. MATERIALS & METHODS: We used dithiocarbamate-functionalized PAMAM dendrimer to cross-link the shell of arginine gold nanoparticles stabilized nanocapsule, and controlled the drug release from the nanocapsule. The ability of cross-linked nanocapsule to deliver hydrophobic paclitaxel to B16F10 cells was demonstrated both in vitro and in vivo. RESULTS: Cross-linked nanocapsule possesses tunable stability and modular permeability, and can deliver paclitaxel with improved anticancer efficiency compared with free drug both in vitro and in vivo. CONCLUSION: Dithiocarbamate chemistry provides a new tool to harness multifactorial colloidal self-assembly for controlled drug delivery for cancer therapy.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Preparações de Ação Retardada/química , Dendrímeros/química , Melanoma/tratamento farmacológico , Nanocápsulas/química , Nanopartículas/química , Paclitaxel/administração & dosagem , Animais , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Arginina/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Ouro/química , Melanoma/patologia , Camundongos , Camundongos Endogâmicos C57BL , Nanocápsulas/ultraestrutura , Nanopartículas/ultraestrutura , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Tiocarbamatos/química
17.
Bioresour Technol ; 201: 121-32, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26642217

RESUMO

Solid additives were used as a microwave absorber to improve the low microwave absorption rate of switchgrass going through pyrolysis, and as a catalyst to improve the bio-oil and biochar characteristics. The synergistic effects were manifested in the presence of a mixture of K3PO4 and clinoptilolite or bentonite compared with single catalyst, resulting in increased microwave absorption rate, and improved bio-oil and biochar quality. The sample of microwave heating switchgrass with 10wt.% K3PO4+10wt.% bentonite reached 400°C after 2.8min, compared with 28.8min through conventional heating, producing biochar with increase in BET surface area from 0.33m(2)/g to 76.3m(2)/g compared with conventional heating. Furthermore, water content of the bio-oil reduced from 22.7 to 15.0wt.% compared with biomass mixed with 20wt.% SiC, a chemically-inert microwave absorbing material used to increase microwave heating. Introducing catalysts showed a great potential for accelerating microwave heating and improving bio-oil and biochar qualities.


Assuntos
Biocombustíveis , Carvão Vegetal/química , Panicum/química , Bentonita/química , Catálise , Calefação/métodos , Micro-Ondas , Fosfatos/química , Compostos de Potássio/química , Zeolitas/química
18.
MethodsX ; 2: 306-15, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26151001

RESUMO

Small gold nanoparticles (sAuNPs, <10 nm in a core diameter) have been used for drug delivery and cancer therapy due to their high payload to carrier ratio. Information about the amount and location of sAuNPs in cells and tissues is critical to many applications. However, the current detection method (i.e., transmission electron microscopy) for such sAuNPs is limited due to the extensive sample preparation and the limited field of view. Here we use confocal laser scanning microscopy to provide endosome-entrapped sAuNP distributions and to quantify particle uptake into cells. The quantitative capabilities of the system were confirmed by inductively coupled plasma-mass spectrometry, with an observed linear relation between scattering intensity and the initial cellular uptake of sAuNPs using 4 nm and 6 nm core particles. The summary of the method is: •This non-invasive imaging strategy provides a tool for label-free real-time tracking and quantification of sAuNPs using a commercially available confocal laser scanning microscope.•Scattering intensity depends on particle size.•The linear relation established between scattering intensity and uptaken gold amount enables simultaneous quantitative assessment through simple image analysis.

19.
Angew Chem Int Ed Engl ; 54(22): 6567-70, 2015 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-25873209

RESUMO

A nanoparticle design featuring pH-responsive alkoxyphenyl acylsulfonamide ligands is reported herein. As a result of ligand structure, this nanoparticle is neutral at pH 7.4, becoming positively charged at tumor pH (<6.5). The particle uptake and cytotoxicity increase over this pH range. This pH-controlled uptake and toxicity makes this particle a promising tool for tumor selective therapy.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Sulfonamidas/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Íons/química , Ligantes , Nanopartículas Metálicas/toxicidade
20.
Int J Environ Res Public Health ; 12(3): 3215-31, 2015 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-25789457

RESUMO

Self-perceived health is a health measure with well-established links with mortality, healthcare services utilization, and future health. Various components of self-perceived health have been identified in different populations. In this study, we aimed to investigate the components of self-perceived health in a Nepali population. This was a cross-sectional survey conducted in the Kailali district of Nepal in 2014. The sample was initially consisted of 309 households, representative of the population of one municipality and one village; however, 304 participants were included in the analyses. Information on socio-demographic characteristics, health condition, satisfaction with healthcare services, psychological factors, and health behaviors was extracted. Logistic regression analyses were carried out to identify putative components of self-perceived health. Among the 304 respondents, 244 (80.3%) and 60 (19.7%) perceived their health as good and poor, respectively. Middle age and lower satisfaction with healthcare services were associated with worse self-perceived health, accounting for 10.3% of variance. No regular exercise, drinking, smoking, and being unhappy were also related with worse self-perceived health, after adjustment for age and satisfaction level. In the final model, however, drinking status did not significantly contribute. Our findings support previous findings that individuals with positive health behaviors and psychological wellbeing are more likely to perceive their health better. This study may direct public health policies toward more targeted interventions.


Assuntos
Atitude Frente a Saúde , Nível de Saúde , Autoimagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Modelos Logísticos , Masculino , Saúde Mental , Pessoa de Meia-Idade , Nepal , Satisfação do Paciente
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