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1.
Sci Rep ; 14(1): 9653, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671018

RESUMO

Due to population growth, climate change, and the urban heat island effect, heat exposure is becoming an important issue faced by urban built environments. Heat exposure assessment is a prerequisite for mitigation measures to reduce the impact of heat exposure. However, there is limited research on urban heat exposure assessment approaches that provides fine-scale spatiotemporal heat exposure information, integrated with meteorological status and human collective exposure as they move about in cities, to enable proactive heat exposure mitigation measures. Smart city digital twins (SCDTs) provide a new potential avenue for addressing this gap, enabling fine spatiotemporal scales, human-infrastructure interaction modeling, and predictive and decision support capabilities. This study aims to develop and test an SCDT for collective urban heat exposure assessment and forecasting. Meteorological sensors and computer vision techniques were implemented in Columbus, Georgia, to acquire temperature, humidity, and passersby count data. These data were then integrated into a collective temperature humidity index. A time-series prediction model and a crowd simulation were employed to predict future short-term heat exposures based on the data accumulated by this SCDT and to support heat exposure mitigation efforts. The results demonstrate the potential of SCDT to enhance public safety by providing city officials with a tool for discovering, predicting, and, ultimately, mitigating community exposure to extreme heat.

2.
Medicina (Kaunas) ; 60(1)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38256421

RESUMO

Background and Objectives: The diagnosis and pathology of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) remain under debate. However, there is a growing body of evidence for an autoimmune component in ME/CFS caused by the Epstein-Barr virus (EBV) and other viral infections. Materials and Methods: In this work, we analyzed a large public dataset on the IgG antibodies to 3054 EBV peptides to understand whether these immune responses could help diagnose patients and trigger pathological autoimmunity; we used healthy controls (HCs) as a comparator cohort. Subsequently, we aimed at predicting the disease status of the study participants using a super learner algorithm targeting an accuracy of 85% when splitting data into train and test datasets. Results: When we compared the data of all ME/CFS patients or the data of a subgroup of those patients with non-infectious or unknown disease triggers to the data of the HC, we could not find an antibody-based classifier that would meet the desired accuracy in the test dataset. However, we could identify a 26-antibody classifier that could distinguish ME/CFS patients with an infectious disease trigger from the HCs with 100% and 90% accuracies in the train and test sets, respectively. We finally performed a bioinformatic analysis of the EBV peptides associated with these 26 antibodies. We found no correlation between the importance metric of the selected antibodies in the classifier and the maximal sequence homology between human proteins and each EBV peptide recognized by these antibodies. Conclusions: In conclusion, these 26 antibodies against EBV have an effective potential for disease diagnosis in a subset of patients. However, the peptides associated with these antibodies are less likely to induce autoimmune B-cell responses that could explain the pathogenesis of ME/CFS.


Assuntos
Infecções por Vírus Epstein-Barr , Síndrome de Fadiga Crônica , Humanos , Síndrome de Fadiga Crônica/diagnóstico , Herpesvirus Humano 4 , Imunoglobulina G , Formação de Anticorpos , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/diagnóstico , Mimetismo Molecular , Peptídeos
3.
Medicine (Baltimore) ; 102(16): e33559, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37083771

RESUMO

Mental health care for students in general, particularly anxiety, is a significant problem that needs more attention, especially during the coronavirus disease 2019 (COVID-19) pandemic. This study aimed to describe the prevalence of anxiety and examine the associated factors among students during the COVID-19 pandemic in Vietnam. A cross-sectional study was conducted from August to September 2021 among 5730 students. An online survey was used to collect sociodemographic information, and the generalized anxiety disorder questionnaire (GAD-7) was used to assess anxiety symptoms among Vietnamese students. Results showed that the prevalence of anxiety among study participants was 16.2% (95% confidence interval [CI]: 15.3%-17.2%). Factors related to anxiety among students were gender, type of housemate, COVID-19 exposure/infection status, vaccination status, health status, academic performance, and social relationships during the COVID-19 pandemic. A significant number of students experienced anxiety during COVID-19, and this rate was related to several factors. Psychological interventions are required to support students during and after the COVID-19 pandemic and other health crises. Further studies are required to confirm our findings.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/psicologia , Pandemias , Estudos Transversais , População do Sudeste Asiático , Vietnã/epidemiologia , SARS-CoV-2 , Depressão/epidemiologia , Ansiedade/epidemiologia , Transtornos de Ansiedade/epidemiologia , Estudantes/psicologia
5.
Australas J Dermatol ; 63(3): 359-364, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35753024

RESUMO

Two patients presented with erythematous papules within larger patches and thin plaques. Following biopsies, each case was initially thought to represent interstitial granulomatous dermatitis (IGD); however, clinicopathological correlation led to a diagnosis of granulomatous mycosis fungoides (GMF). Drawing upon the similarities between these cases, this report explores the clinical and histological manifestations of GMF, features distinguishing GMF from other granulomatous diseases like IGD and the prognostic significance of distinguishing GMF from classic mycosis fungoides. This report also shows that despite the potential for histological overlap between GMF and IGD, the existing literature does not reveal an epidemiological or pathophysiological link between these two conditions.


Assuntos
Micose Fungoide , Neoplasias Cutâneas , Fator de Maturação da Glia , Granuloma/diagnóstico , Granuloma/patologia , Humanos , Imunoglobulina D , Micose Fungoide/diagnóstico , Micose Fungoide/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia
6.
Waste Manag ; 141: 16-26, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35085867

RESUMO

Waste food utilization to produce bio-oil through pyrolysis has received increasing attention. The feedstock can be utilized more efficiently as its properties are upgraded. In this work, the mixed food waste (MFW) was pretreated via torrefaction at moderate temperatures (250-275 °C) under an inert atmosphere before fast pyrolysis. The pyrolysis of torrified MFW (T-MFW) was performed in a bubbling fluidized-bed reactor (FBR) to study the influence of torrefaction on the pyrolysis product distribution and bio-oil compositions. The highest liquid yield of 39.54 wt% was observed at a pyrolysis temperature of 450℃. The torrefaction has a significant effect on the pyrolysis process of MFW. After torrefaction, the higher heating values (HHVs) of the pyrolysis bio-oils (POs) ranged from 31.51 to 34.34 MJ/kg, which were higher than those of bio-oils from raw MFW (27.69-31.58 MJ/kg). The POs mainly contained aliphatic hydrocarbons (alkenes and ketones), phenolic, and N-containing derivatives. The pyrolysis of T-MFW was also carried out under the CO2 atmosphere. The application of CO2 as a carrier gas resulted in a decrease in the liquid yield and an increase in the gas product yield. In addition, the carbon and nitrogen content of POs increased, whereas the oxygen was reduced via the release of moisture and CO. Using CO2 in pyrolysis inhibited the generation of nitriles derivatives in POs, which are harmful to the environment. These results indicated that the application of CO2 to the thermal treatment of T-MFW could be feasible in energy production as well as environmental pollution control.

7.
Int J Med Robot ; 17(6): e2325, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34425041

RESUMO

BACKGROUND: Shear force is important for tumour detection and can contribute to minimally invasive surgery (MIS). A popular method uses lateral skin stretch to produce shear force but has some limitations. METHODS: We have developed a ring-type pneumatic tactile display that employs normal indentation substituted for lateral skin stretch to represent normal and shear feedback, called SuP-Ring. Psychophysical experiments were conducted to evaluate how users perceive the provided feedback and the effectiveness of SuP-Ring in tumour localisation. RESULTS: The experimental results show that the participants could perceive the provided normal and shear feedback well. Shear feedback enables users to enhance their performance in localising the tumour and normal feedback could contribute to ensuring the safety requirements in MIS. CONCLUSIONS: The proposed tactile display could be useful for intraoperative tumour localisation and has the potential to be used in a wide variety of applications.


Assuntos
Percepção do Tato , Tato , Retroalimentação , Humanos , Fenômenos Mecânicos , Procedimentos Cirúrgicos Minimamente Invasivos
8.
Angew Chem Int Ed Engl ; 60(34): 18876-18881, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34170591

RESUMO

Although being attractive materials for photoelectrochemical hydrogen evolution reaction (PEC HER) under neutral or acidic conditions, conjugated polymers still show poor PEC HER performance in alkaline medium due to the lack of water dissociation sites. Herein, we demonstrate that tailoring the polymer skeleton from poly(diethynylthieno[3,2-b]thiophene) (pDET) to poly(2,6-diethynylbenzo[1,2-b:4,5-b']dithiophene (pBDT) and poly(diethynyldithieno[3,2-b:2',3'-d]thiophene) (pDTT) in conjugated acetylenic polymers (CAPs) introduces highly efficient active sites for water dissociation. As a result, pDTT and pBDT, grown on Cu substrate, demonstrate benchmark photocurrent densities of 170 µA cm-2 and 120 µA cm-2 (at 0.3 V vs. RHE; pH 13), which are 4.2 and 3 times higher than that of pDET, respectively. Moreover, by combining DFT calculations and electrochemical operando resonance Raman spectroscopy, we propose that the electron-enriched Cß of the outer thiophene rings of pDTT are the water dissociation active sites, while the -C≡C- bonds function as the active sites for hydrogen evolution.

9.
Environ Pollut ; 275: 116023, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33582642

RESUMO

Biofuel production via pyrolysis has received increasing interest as a promising solution for utilization of now wasted food residue. In this study, the fast pyrolysis of mixed food waste (MFW) was performed in a bubbling fluidized-bed reactor. This was done under different operating conditions (reaction temperatures and carrier gas flow rate) that influence product distribution and bio-oil composition. The highest liquid yield (49.05 wt%) was observed at a pyrolysis temperature of 475 °C. It was also found that the quality of pyrolysis bio-oils (POs) could be improved using catalysts. The catalytic fast pyrolysis of MFW was studied to upgrade the pyrolysis vapor, using dolomite, red mud, and HZSM-5. The higher heating values (HHVs) of the catalytic pyrolysis bio-oils (CPOs) ranged between 30.47 and 35.69 MJ/kg, which are higher than the HHVs of non-catalytic pyrolysis bio-oils (27.69-31.58 MJ/kg). The major components of the bio-oils were fatty acids, N-containing compounds, and derivatives of phenol. The selectivity for bio-oil components varied depending on the catalysts. In the presence of the catalysts, the oxygen was removed from oxygenates via moisture, CO2, and CO. The CPOs contained aliphatic hydrocarbons, polycyclic aromatic compounds (such as naphthalene), pyridine derivatives, and light oxygenates (cyclic alkenes and ketones).


Assuntos
Pirólise , Eliminação de Resíduos , Biocombustíveis , Catálise , Alimentos , Temperatura Alta
10.
Bioresour Technol ; 241: 610-619, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28605725

RESUMO

In this work, the hydrothermal liquefaction (HTL) of microalgal Tetraselmis sp. was conducted at various reaction temperatures (250-350°C) and reaction times (10-60min). A general reaction network and a quantitative kinetic model were proposed for the HTL of microalgae. In this reaction network, the primary decomposition of lipids, proteins, and carbohydrates generated heavy oil (HO), light oil (LO), and aqueous-phase (AP) products. Then, reversible interconversions and further decomposition of these product fractions to produce gas product were followed. The model accurately captures the trends observed in the experimental data. Analyses of the kinetic parameters (reaction rate constants and activation energies) suggested the dominant reaction pathways as well as the contribution of the biochemical compositions to the bio-oil yield. Finally, the kinetic parameters calculated from the model were utilized to explore the parameter space in order to predict the liquefaction product yields depending on the reaction time and temperature.


Assuntos
Biotecnologia , Clorófitas , Microalgas , Cinética , Temperatura
11.
J Vet Med Sci ; 79(3): 479-485, 2017 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-28123141

RESUMO

In this study, we attempted to isolate Escherichia coli from healthy adults in Ho Chi Minh City, Vietnam, and characterized its antimicrobial resistance profile, extended-spectrum ß-lactamase (ESBL) genotype, phylogenetic grouping and virulence gene profile. A total of 103 E. coli isolates were obtained, and most of them were antimicrobial resistant such to streptomycin (80.6%), tetracycline (67.0%), ampicillin (65.0%), sulfamethoxsazole/trimethoprim (48.5%), nalidixic acid (43.7%), chloramphenicol (34.0%), cefotaxime (15.5%), ciprofloxacin (15.5%), kanamycin (12.6%), ceftazidime (10.7%), fosfomycin (4.9%) and gentamicin (2.9%). However, all these E. coli strains were susceptible to imipenem. Surprisingly, of 103 strains, 74 (71.8%) and 43 (41.7%) strains showed resistance to more than 3 and 5 classes of antimicrobials, respectively. Furthermore, 10 E. coli strains were ESBL-producers and positive for blaCTX-M genes (7 for blaCTX-M-9 and 3 for blaCTX-M-1), while five were additionally positive for blaTEM genes. S1-nuclease pulsed-field gel electrophoresis analysis revealed that 7 and 3 strains of E. coli carry blaCTX-M genes on their large plasmid and chromosome, respectively. Phylogenetic analysis exhibited that majority of the E. coli strains was grouped into A (44.7%), followed by B1 (23.3%), B2 (18.4%) and D (13.6%). Virulence genes associated with diarrheagenic E. coli, such as astA, EAF, eaeA, elt and eagg were also detected in ESBL-producing E. coli as well as antimicrobial resistant strains. These data suggest that commensal E. coli of healthy human could be a reservoir for antimicrobial resistance determinants and some of them might be harmful to human.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Adulto , Idoso , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Escherichia coli/patogenicidade , Fezes/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Vietnã , Virulência/genética , Adulto Jovem , beta-Lactamases/metabolismo
12.
Bioresour Technol ; 139: 242-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23665684

RESUMO

Alga Sagarssum sp. can be converted to bio-oil, gas, and char through pyrolysis. In this study, the pyrolysis characteristics and kinetics of Sagarssum sp. were investigated using a thermogravimetric analyzer and tubing reactor, respectively. Sagarssum sp. decomposed below 550°C, but the majority of materials decomposed between 200 and 350°C at heating rates of 5-20°C/min. The apparent activation energy increased from 183.53 to 505.57 kJ mol(-1) with increasing pyrolysis conversion. The kinetic parameters of Sagarssum sp. pyrolysis were determined using nonlinear least-squares regression of the experimental data, assuming second-order kinetics. The proposed lumped kinetic model represented the experimental results well and the kinetic rate constants suggested a predominant pyrolysis reaction pathway from Sagarssum sp. to bio-oil, rather than from Sagarssum sp. to gas. The kinetic rate constants indicated that the predominant reaction pathway was A (Sagarssum sp.) to B (bio-oil), rather than A (Sagarssum sp.) to C (gas; C1-C4).


Assuntos
Biomassa , Temperatura Alta , Alga Marinha/metabolismo , Termogravimetria/métodos , Elementos Químicos , Cromatografia Gasosa-Espectrometria de Massas , Cinética , Óleos de Plantas
13.
ChemSusChem ; 6(3): 487-92, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23371822

RESUMO

The electron transfer (ET) processes of electroactive microbial biofilms have been investigated by combining electrochemistry and time-resolved surface-enhanced resonance Raman (TR-SERR) spectroscopy. This experimental approach provides selective information on the ET process across the biofilm-electrode interface by monitoring the redox-state changes of heme cofactors in outer membrane cytochromes (OMCs) that are in close vicinity (i.e., within 7 nm) to the Ag working electrode. The rate constant for heterogeneous ET of the surface-confined OMCs (sc-OMCs) of a mixed culture derived electroactive microbial biofilm has been determined to be 0.03 s(-1) . In contrast, according to kinetic simulations the ET between sc-OMCs and their redox partners, embedded within the biofilm, is a much faster process with an estimated rate constant greater than 1.2 s(-1) . The slow rate of heterogeneous ET and the lack of high-spin species in the SERR spectra rule out the direct attachment of the sc-OMCs to the electrode surface.


Assuntos
Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Reatores Biológicos/microbiologia , Análise Espectral Raman , Citocromos/metabolismo , Eletrodos , Transporte de Elétrons , Prata/química , Propriedades de Superfície
14.
Bioresour Technol ; 123: 445-51, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22940354

RESUMO

Saccharina japonica can be converted to bio-oil, gas, and char through pyrolysis. In this study, the pyrolysis characteristics of S. japonica were investigated using a thermogravimetric analyzer. Most of the materials decomposed between 200°C and 350°C at heating rates of 10-20°C/min. The apparent activation energy increased from 102.5kJmol(-1) to 269.7kJmol(-1) with increasing pyrolysis conversion. The kinetic parameters of S. japonica pyrolysis were determined using nonlinear least-squares regression of the experimental data assuming first-order kinetics. The kinetic rate constants indicated that the predominant reaction pathway was B (bio-oil) to C (gas; C(1)-C(4)), rather than A (S. japonica) to B (bio-oil) and/or to C (gas; C(1)-C(4)). The proposed lumped kinetics of S. japonica pyrolysis offers a guide for the scale-up of the process at the research and industrial level.


Assuntos
Phaeophyceae/química , Temperatura , Biomassa , Biotecnologia/instrumentação , Carvão Vegetal/química , Elementos Químicos , Cinética , Óleos/química , Termogravimetria
15.
J Phys Chem B ; 115(31): 9556-63, 2011 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-21718003

RESUMO

Poly(L-lactic acid) (PLLA) intercalated nanocomposite films containing 1, 2, 5, and 10% organically modified montmorillonite (OMMT) have been synthesized by the solvent casting approach. The thermal characteristics, isothermal cold crystallization kinetics, and structural changes of neat PLLA and its nanocomposites during annealing were studied by using differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy. DSC observation showed that melting temperature and final crystallinity were not affected significantly with OMMT loading. PLLA films with increasing OMMT content exhibited higher crystallization rates than neat PLLA during annealing and suggested that the silicate platelets act as a nucleation agent during annealing. The effect of OMMT content on the isothermal crystallization kinetics of PLLA was analyzed using the Avrami equation. An Avrami constant of 1-2 was observed, suggesting that crystallization proceeds through one-dimensional growth with heterogeneous nucleation. FTIR investigation showed a band at 922 cm(-1) at all T(a), and no band at 908 cm(-1) suggested that all samples form α crystal regardless of OMMT content or T(a).


Assuntos
Ácido Láctico/química , Nanocompostos/química , Polímeros/química , Bentonita/química , Varredura Diferencial de Calorimetria , Cristalização , Cinética , Poliésteres , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura de Transição , Difração de Raios X
17.
Chemphyschem ; 11(6): 1225-35, 2010 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-20376873

RESUMO

The heterogeneous electron-transfer (ET) reaction of cytochrome c (Cyt-c) electrostatically or covalently immobilized on electrodes coated with self-assembled monolayers (SAMs) of omega-functionalized alkanethiols is analyzed by surface-enhanced resonance Raman (SERR) spectroscopy and molecular dynamics (MD) simulations. Electrostatically bound Cyt-c on pure carboxyl-terminated and mixed carboxyl/hydroxyl-terminated SAMs reveals the same distance dependence of the rate constants, that is, electron tunneling at long distances and a regime controlled by the protein orientational distribution and dynamics that leads to a nearly distance-independent rate constant at short distances. Qualitatively, the same behavior is found for covalently bound Cyt-c, although the apparent ET rates in the plateau region are lower since protein mobility is restricted due to formation of amide bonds between the protein and the SAM. The experimental findings are consistent with the results of MD simulations indicating that thermal fluctuations of the protein and interfacial solvent molecules can effectively modulate the electron tunneling probability.


Assuntos
Citocromos c/química , Eletrodos , Transporte de Elétrons , Proteínas Imobilizadas/química , Cinética , Simulação de Dinâmica Molecular , Oxirredução , Análise Espectral Raman , Eletricidade Estática , Termodinâmica
18.
J Am Chem Soc ; 130(30): 9844-8, 2008 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-18593159

RESUMO

Heterogeneous electron transfer of proteins at biomimetic interfaces is characterized by unusual distance dependences of the electron-transfer rates, whose origin has been elusive and controversial. Using a two-color, time-resolved, surface-enhanced resonance Raman spectroelectrochemical approach, we have been able to monitor simultaneously and in real time the structure, electron-transfer kinetics, and configurational fluctuations of cytochrome c electrostatically adsorbed to electrodes coated with self-assembled monolayers. Our results show that the overall electron-transfer kinetics is determined by protein dynamics rather than by tunnelling probabilities and that the protein dynamics in turn is controlled by the interfacial electric field. Implications for interprotein electron transfer at biological membranes are discussed.


Assuntos
Citocromos c/química , Eletroquímica/métodos , Análise Espectral Raman/métodos , Citocromos c/metabolismo , Eletrodos , Elétrons , Cinética , Conformação Proteica , Prata/química , Compostos de Sulfidrila/química
20.
J Gen Virol ; 88(Pt 5): 1479-1483, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17412976

RESUMO

Two novel human papillomaviruses (HPVs), HPV93 and HPV96, with genomes of 7450 and 7438 bp, respectively, are described. The L1 open reading frame of HPV93 showed highest identity to HPV24 (79%) and that of HPV96 had highest identity to HPV92 (71%). Real-time PCR for HPV92, 93 and 96 on stripped biopsies from tumours and healthy skin from 269 immunocompetent patients found HPV DNA in 2.6% of tumours and in 0.4% of healthy skin samples. Double infections were observed in two tumours. HPV92 was detected in four, HPV93 in two and HPV96 in three tumours. The range of viral loads spanned from one copy per 45 cells to one copy per 10,000 cells. The E7 proteins of HPV92, 93 and 96 were found to bind the retinoblastoma protein (pRb). These results suggest a possible role for these HPV types in skin carcinogenesis that deserves further study.


Assuntos
Fases de Leitura Aberta , Papillomaviridae/genética , Pele/virologia , Primers do DNA , DNA Viral/genética , DNA Viral/isolamento & purificação , Genoma Viral , Humanos , Dados de Sequência Molecular , Papillomaviridae/classificação , RNA Mensageiro/genética , RNA Viral/genética , Valores de Referência
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