RESUMO
A quantitative understanding of the coupled dynamics of flow and particles in aerosol and droplet transmission associated with speech remains elusive. Here, we summarize an effort that integrates insights into flow-particle dynamics induced by the production plosive sounds during speech with skin-integrated electronic systems for monitoring the production of these sounds. In particular, we uncover diffusive and ballistic regimes separated by a threshold particle size and characterize the Lagrangian acceleration and pair dispersion. Lagrangian dynamics of the particles in the diffusive regime exhibit features of isotropic turbulence. These fundamental findings highlight the value in skin-interfaced wireless sensors for continuously measuring critical speech patterns in clinical settings, work environments, and the home, based on unique neck biomechanics associated with the generation of plosive sounds. We introduce a wireless, soft device that captures these motions to enable detection of plosive sounds in multiple languages through a convolutional neural network approach. This work spans fundamental flow-particle physics to soft electronic technology, with implications in monitoring and studying critical speech patterns associated with aerosol and droplet transmissions relevant to the spread of infectious diseases.
Assuntos
Eletrônica , Fala , Aerossóis , Tamanho da Partícula , Movimento (Física)RESUMO
This study evaluated the effects of Bougainvillea glabra (BG) leaf as a feed supplement on growth, skin mucosal immune parameters, serum oxidative stress, expression of immune-related genes, and susceptibility to pathogen infection in carp Cyprinus carpio. Diets containing four different BG concentrations (g kg-1), i.e., 0 g (basal diet), 20 g (BG20), 30 g (BG30), 40 g (BG40), and 50 g (BG50), were fed to the carp (average weight: 14.03 ± 0.81 g) for 8 weeks. Skin mucosal immunological and serum antioxidant parameters were examined 8 weeks post-feeding. Growth performance was significantly higher in BG40. Among the examined skin mucosal immune parameters, lysozyme (33.79 ± 0.98 U mL-1), protein (6.88 ± 0.37 mg mL-1), immunoglobulin (IgM; 5.34 ± 0.37 unit-mg mL-1), and protease activity (3.18 ± 0.36%) were significantly higher in BG40 than in the control; whereas, there was no significant effect on the alkaline phosphatase level. Among serum immune activity, activities of lysozyme, the alternative complement pathway, and IgM were significantly higher in BG40. Phagocytic, and superoxide dismutase (SOD) activities were higher (P < 0.05) in BG30-BG50. Serum ALT, AST, and MDA levels were lower in BG40 than in the control (P < 0.05). Intestinal enzymatic activities were enhanced in BG40 and BG50 (P < 0.05), except for lipase in BG50. Gene expression analysis revealed that the mRNA expressions of antioxidant genes (SOD, GPx, and Nrf2), an anti-inflammatory gene (IL-10), and IκBα were significantly upregulated in BG40. Conversely, the pro-inflammatory gene IL-1ß and the signaling molecule NF-κB p65 were downregulated in BG40 and BG50, respectively. BG supplementation had no significant effect on TNF-α, TLR22, or HSP70 mRNA expressions. Moreover, fish in BG40 exhibited the highest relative post-challenge survival (67.74%) against Aeromonas hydrophila infection. These results suggested that dietary supplementation with BG leaves at 40 g/kg can significantly improve the growth performance, immune responses, and disease resistance of C. carpio. BG leaves are a promising food additive for carp in aquaculture.
Assuntos
Carpas , Infecções por Bactérias Gram-Negativas , Animais , Resistência à Doença , Carpas/metabolismo , Antioxidantes/metabolismo , Muramidase/farmacologia , Imunidade nas Mucosas , Suplementos Nutricionais/análise , Dieta/veterinária , RNA Mensageiro/metabolismo , Imunoglobulina M , Folhas de Planta , Superóxido Dismutase/farmacologia , Ração Animal/análiseRESUMO
In a large acute myelitis cohort, we aimed to determine whether brighter spotty lesions (BSLs)-using the refined terminology-on spinal magnetic resonance imaging (MRI) help distinguish aquaporin-4 antibody-positive neuromyelitis optica spectrum disorder (AQP4-NMOSD) from myelin oligodendrocyte glycoprotein antibody disease (MOGAD). An experienced neuro-radiologist and two neurologists independently analyzed 133 spinal MRI scans (65 from MOGAD and 68 from AQP4-NMOSD) acquired within 1 month of attacks. BSLs were observed in 18 of 61 (30%) participants with AQP4-NMOSD, while none of 49 participants with MOGAD showed BSL (p < 0.001). BSL during the acute phase would be useful to differentiate AQP4-NMOSD from MOGAD.
Assuntos
Aquaporina 4 , Neuromielite Óptica , Autoanticorpos , Humanos , Imageamento por Ressonância Magnética , Glicoproteína Mielina-Oligodendrócito , Neuromielite Óptica/diagnóstico por imagem , Estudos RetrospectivosRESUMO
This study aims to analyse the effect of an Enterococcus faecium SLB 130 probiotic on the growth performance, nutrient digestibility, and blood profile in weaning pigs. A total of 200 weaning pigs were taken and assigned to 1 of 5 dietary treatments according to their average initial body weight and sex in a complete randomised block design. The experimental diets were as follows: CON - basal diet, and the basal diet supplemented with 2.5 × 105 cfu/g (TRT1), 1.29 × 106 cfu/g (TRT2), 1.15 × 107 cfu/g (TRT3), and 1.1 × 108 cfu/g (TRT4) of E. faecium for 6 weeks. Pigs fed a diet containing an E. faecium SLB 130 probiotic supplement significantly increased (P < 0.05) the body weight, average daily gain, and average daily feed intake at weeks 1, 3, 6, and the overall period. In addition, the E. faecium SLB 130 (P < 0.05) supplement group pigs showed an increased gain to feed ratio at week 6 and the overall experimental period. Moreover, the dietary inclusion of the E. faecium SLB 130 probiotic supplement linearly increased (P < 0.05) the nutrient digestibility of the dry matter and nitrogen, however, there were no improvements observed on weanling pigs' blood profile. In summary, the inclusion of an E. faecium SLB 130 probiotic additive in the weanling pigs' diet would be beneficial to enhance their growth performance and nutrient digestibility.
RESUMO
A new series of strongly coupled oscillators based upon (porphinato)Pd, (porphinato)Pt, and bis(terpyridyl)ruthenium(II) building blocks is described. These RuPPd, RuPPt, RuPPdRu, and RuPPtRu chromophores feature bis(terpyridyl)Ru(II) moieties connected to the (porphinato)metal unit via an ethyne linker that bridges the 4'-terpyridyl and porphyrin macrocycle meso-carbon positions. Pump-probe transient optical data demonstrate sub-picosecond excited singlet-to-triplet-state relaxation. The relaxed lowest-energy triplet (T1) excited states of these chromophores feature absorption manifolds that span the 800-1200 nm spectral region, microsecond triplet-state lifetimes, and large absorptive extinction coefficients [ε(T1 â Tn) > 4 × 104 M-1 cm-1]. Dynamic hyperpolarizability (ßλ) values were determined from hyper-Rayleigh light scattering (HRS) measurements carried out at several incident irradiation wavelengths over the 800-1500 nm spectral region. Relative to benchmark RuPZn and RuPZnRu chromophores which showed large ßHRS values over the 1200-1600 nm range, RuPPd, RuPPt, RuPPdRu, and RuPPtRu displayed large ßHRS values over the 850-1200 nm region. Generalized Thomas-Kuhn sum (TKS) rules and experimental hyperpolarizability values were utilized to determine excited state-to-excited state transition dipole terms from experimental electronic absorption data and thus assessed frequency-dependent ßλ values, including two- and three-level contributions for both ßzzz and ßxzx tensor components to the RuPPd, RuPPt, RuPPdRu, and RuPPtRu hyperpolarizability spectra. These analyses qualitatively rationalize how the ßzzz and ßxzx tensor elements influence the observed irradiation wavelength-dependent hyperpolarizability magnitudes. The TKS analysis suggests that supermolecules related to RuPPd, RuPPt, RuPPdRu, and RuPPtRu will likely feature intricate dependences of experimentally determined ßHRS values as a function of irradiation wavelength that derive from substantial singlet-triplet mixing, and complex interactions among multiple different ß tensor components that modulate the long wavelength regime of the nonlinear optical response.
RESUMO
Background and Objectives: Phase lag entropy, an electroencephalographic monitor, evaluates the variety in temporal patterns of phase relationship between frontal and prefrontal brain region. Phase lag entropy can reflect the depth of anesthesia induced by propofol, but the association between sevoflurane and phase lag entropy has not been elucidated. This study examined the effect of sevoflurane on phase lag entropy during induction of general anesthesia. We also explored the pharmacodynamic model between end-tidal anesthetic concentration and electroencephalographic monitor. Materials and Methods: A total of 20 patients were enrolled. General anesthesia was produced by escalating the sevoflurane (1 vol% up to 8 vol%). The relationship between phase lag entropy and end-tidal anesthetic concentration was analyzed. A non-linear mixed-effects model was used to get the relationship of pharmacodynamics between the end-tidal sevoflurane concentration and phase lag entropy. Mean blood pressure, heart rate, and the modified observer's assessment of alertness/sedation scale were also recorded during sevoflurane anesthesia. Results: As level of sedation increased, phase lag entropy decreased. A significant correlation was showed between phase lag entropy and end-tidal sevoflurane concentration (r = -0.759, p < 0.001). The correlation coefficient between the modified observer's assessment of alertness/sedation scale and phase lag entropy was 0.731 (p < 0.001). The pharmacodynamic factors assessed by the sigmoid Emax model were E0 = 84.9, Emax = 42, Ce50 = 1.81, γ = 4.78, and ke0 = 0.692. The prediction probability of phase-lag entropy for measuring the modified observer's assessment of alertness/sedation scale and end-tidal sevoflurane concentration were 0.764 and 0.789, respectively. With the increasing concentration of sevoflurane, mean blood pressure decreased, but heart rate did not change. Conclusions: The continuing escalation in end-tidal sevoflurane concentration caused a decline in phase lag entropy. Phase lag entropy can serve as an indicator of hypnotic depth in patients receiving sevoflurane anesthesia.
Assuntos
Hipnóticos e Sedativos , Propofol , Anestesia Geral , Eletroencefalografia , Entropia , Humanos , SevofluranoRESUMO
INTRODUCTION: Leriche syndrome is an aortoiliac occlusive disease caused by atherosclerotic occlusion. We report a case of Leriche syndrome with a fracture that was suspected as complex regional pain syndrome (CRPS), as the post-traumatic pain gradually worsened in the form of excruciating neuropathic pain. CASE REPORT: A 52-year-old woman with a history of hypertension was referred to the Department of Pain Medicine from a local orthopedic clinic because of suspected CRPS for excruciating neuropathic pain for one month. She complained of gait dysfunction and severe pain in the right foot following an incident of trauma with the right first toe. The average pain intensity assessed using the visual analog scale (VAS) was 90 (0: no pain, 100: the worst pain imaginable), and the neuropathic pain was evident as a score of 6/10 on Douleur neuropathique 4. Allodynia, hyperalgesia, blue discoloration of the skin, asymmetric temperature change (1.38 °C), and edematous soft tissue changes were observed. Ultrasonography showed a chip fracture in the first distal phalanx of the right first toe. The diagnosis was most probably CRPS type I according to the Budapest research criteria for CRPS. However, multiple pain management techniques were insufficient in controlling the symptoms. A month and a half later, an ankle-brachial index score of less than 0.4 suggested severe peripheral artery disease. Computed tomography angiography showed total occlusion between the infrarenal abdominal aorta and the bilateral common iliac arteries. Therefore, she underwent aortic-bifemoral bypass surgery with a diagnosis of Leriche syndrome. Three months after the surgery, the average pain intensity was graded as 10 on the VAS (0-100), the color of the skin of the right first toe improved and no gait dysfunction was observed. CONCLUSION: A chip fracture in a region with insufficient blood flow could manifest as excruciating neuropathic pain in Leriche syndrome.
Assuntos
Síndromes da Dor Regional Complexa , Síndrome de Leriche , Neuralgia , Aorta Abdominal , Síndromes da Dor Regional Complexa/diagnóstico , Síndromes da Dor Regional Complexa/etiologia , Erros de Diagnóstico , Feminino , Humanos , Síndrome de Leriche/complicações , Síndrome de Leriche/diagnóstico , Pessoa de Meia-Idade , Neuralgia/diagnóstico , Neuralgia/etiologiaRESUMO
Molecular assemblies in metal-organic frameworks (MOFs) are reminiscent of natural light-harvesting (LH) systems and considered as emerging materials for energy conversion. Such applications require understanding the correlation between their excited-state properties and underlying topological net. Two chemically identical but topologically different tetraphenylpyrene (1,3,6,8-tetrakis( p-benzoicacid)pyrene; H4TBAPy)-based ZrIV MOFs, NU-901 ( scu) and NU-1000 ( csq), are chosen to computationally and spectroscopically interrogate the impact of topological difference on their excited-state electronic structures. Time-dependent density functional theory-computed transition density matrices for selected model compounds reveal that the optically relevant S1, S2, and S n states are delocalized over more than four TBAPy linkers with a maximum exciton size of â¼1.7 nm (i.e., two neighboring TBAPy linkers). Computational data further suggests the evolution of polar excitons (hole and electron residing in two different linkers); their oscillator strengths vary with the extent of interchromophoric interaction depending on their topological network. Femtosecond transient absorption (fs-TA) spectroscopic data of NU-901 highlight instantaneous spectral evolution of an intense S1 â S n transition at 750 nm, which diminishes with the emergence of a broad (580-1100 nm) induced absorption originating from a fast excimer formation. Although these ultrafast spectroscopic data reveal the first direct spectral observation of fast excimer formation (τ = 2 ps) in MOFs, the fs-TA features seen in NU-901 are clearly absent in NU-1000 and the free H4TBAPy linker. Furthermore, transient and steady-state fluorescence data collected as a function of solvent dielectrics reveal that the emissive states in both MOF samples are electronically nonpolar; however, low-lying polar excited states may get involved in the excited-state decay processes in polar solvents. The present work shows that the topological arrangement of the linkers critically controls the excited-state electronic structures.
RESUMO
Metal-organic frameworks (MOFs) are emerging materials for electro- and photo-chemical applications, where an understanding of the underlying charge-transfer (CT) process will facilitate designing new materials. However, the involvement of counterions in traditional electrochemical experiments complicates the probe on the role of various components during a CT event. A CT reaction between photoexcited MOF linker and a node-anchored ferrocene, within mesoporous framework NU-1000, was spectroscopically probed without the involvement of electrolyte based counterions. Dielectric dependent CT kinetics indicate that the process involves a high reorganization energy that is required to polarize the node bound hydroxyl/aqua ligands. The findings have clear implication on the design of MOF-based electrocatalysis and photoelectrochemical devices.
RESUMO
AIMS: Regional cerebral oxygen saturation (rSO2 ) is currently the most used measure in clinical practice to monitor cerebral ischaemia in patients undergoing carotid endarterectomy (CEA). Although end-tidal carbon dioxide (PET CO2 ) is known as a factor that influences rSO2 , the relationship between PET CO2 and rSO2 has not been quantitatively evaluated in patients with severe arteriosclerosis. This study aimed to evaluate the effect of PET CO2 on rSO2 in patients undergoing CEA under general anaesthesia. METHODS: The intervention to change PET CO2 was conducted between skin incision and clamping of the carotid artery. The rSO2 values were observed by changing PET CO2 in the range of 25-45 mmHg. The PET CO2 -rSO2 relationship was characterized by population analysis using a turnover model. RESULTS: In total, 1651 rSO2 data points from 30 patients were used to determine the pharmacodynamic characteristics. Hypertension (HTN) and systolic blood pressure (SBP) were significant covariates on the slope factor in the stimulatory effect of PET CO2 on rSO2 and fractional turnover rate constant (kout ), respectively. The estimates of the parameters were kout (min-1 ): 3.59 for SBP <90 mmHg and 0.491 for SBP ≥90 mmHg, slope: 0.00321 for patients with HTN and 0.00664 for patients without HTN. CONCLUSION: The presence of HTNattenuates the response of rSO2 after a change in PET CO2 . When cerebral blood flow is in a state of decline caused by a decrease in SBP to <90 mmHg, the response of rSO2 to PET CO2 is increased. It is advisable to maintain SBP >90 mmHg in patients with HTNduring CEA.
Assuntos
Dióxido de Carbono/sangue , Circulação Cerebrovascular/fisiologia , Endarterectomia das Carótidas , Monitorização Intraoperatória/métodos , Oxigênio/sangue , Idoso , Anestesia Geral , Pressão Sanguínea/fisiologia , Isquemia Encefálica/sangue , Isquemia Encefálica/etiologia , Endarterectomia das Carótidas/efeitos adversos , Feminino , Humanos , Masculino , Modelos Teóricos , Oximetria , Respiração Artificial/métodosRESUMO
In response to ulcerative mucosal injuries, intestinal epithelial restitution is a critical event in the early defense against harmful attacks by luminal Ags. Based on the assumption that epithelial NAG-1 is an endogenous regulator of ulcerative stress-induced injuries, the expression and functions of NAG-1 were investigated. Genetic ablation of NAG-1 decreased survival of mice with dextran sodium sulfate-induced intestinal ulcer and histologically delayed the epithelial restitution, confirming early protective roles of NAG-1 in ulcerative insults. Moreover, enhanced expression of NAG-1 during the wound-healing process was associated with epithelial cell migration and spreading. In response to ulcerative injury, RhoA GTPase, a cytoskeleton modulator, mediated epithelial restitution via enhanced motility. RhoA expression was prominently elevated in the restituting epithelia cells around the insulted wound bed and was attenuated by NAG-1 deficiency. Pharmacological intervention with RhoA thus attenuated NAG-1-mediated epithelial cell migration during epithelial restitution. Taken together, epithelial restitution was promoted by enhanced NAG-1 expression and subsequent enterocyte locomotion during the early wound-healing process, suggesting clinical usefulness of NAG-1 as a novel endogenous muco-protective factor or an indicator of therapeutic efficacy against the ulcerative gastrointestinal diseases, including inflammatory bowel disease.
Assuntos
Doença de Crohn/metabolismo , Enterócitos/imunologia , Fator 15 de Diferenciação de Crescimento/metabolismo , Cicatrização/fisiologia , Adolescente , Adulto , Animais , Western Blotting , Linhagem Celular , Criança , Doença de Crohn/patologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Úlcera , Adulto JovemRESUMO
Patients with chronic intestinal ulcerative diseases, such as inflammatory bowel disease, tend to exhibit abnormal lipid profiles, which may affect the gut epithelial integrity. We hypothesized that epithelial cholesterol depletion may trigger inflammation-checking machinery via cholesterol sentinel signaling molecules whose disruption in patients may aggravate inflammation and disease progression. In the present study, sterol regulatory element-binding protein 2 (SREBP2) as the cholesterol sentinel was assessed for its involvement in the epithelial inflammatory responses in cholesterol-depleted enterocytes. Patients and experimental animals with intestinal ulcerative injuries showed suppression in epithelial SREBP2. Moreover, SREBP2-deficient enterocytes showed enhanced pro-inflammatory signals in response to inflammatory insults, indicating regulatory roles of SREBP2 in gut epithelial inflammation. However, epithelial cholesterol depletion transiently induced pro-inflammatory chemokine expression regardless of the well known pro-inflammatory nuclear factor-κB signals. In contrast, cholesterol depletion also exerts regulatory actions to maintain epithelial homeostasis against excessive inflammation via SREBP2-associated signals in a negative feedback loop. Mechanistically, SREBP2 and its induced target EGR-1 were positively involved in induction of peroxisome proliferator-activated receptor γ (PPARγ), a representative anti-inflammatory transcription factor. As a crucial target of the SREBP2-EGR-1-PPARγ-associated signaling pathways, the mRNA stabilizer, human antigen R (HuR) was retained in nuclei, leading to reduced stability of pro-inflammatory chemokine transcripts. This mechanistic investigation provides clinical insights into protective roles of the epithelial cholesterol deficiency against excessive inflammatory responses via the SREBP2-HuR circuit, although the deficiency triggers transient pro-inflammatory signals.
Assuntos
Colesterol/deficiência , Colite Ulcerativa/metabolismo , Proteína Semelhante a ELAV 1/metabolismo , Enterócitos/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Linhagem Celular , Colite Ulcerativa/genética , Proteína Semelhante a ELAV 1/genética , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Enterócitos/patologia , Humanos , Inflamação/genética , Inflamação/metabolismo , NF-kappa B/genética , NF-kappa B/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/genéticaRESUMO
Ultrafast photoinduced electron transfer (PIET) dynamics of a C70-encapsulated bisporphyrin covalent organic polyhedron hybrid (C70@COP-5) is studied in a nonpolar toluene medium with fluorescence and transient absorption spectroscopies. This structurally rigid donor (D)-acceptor (A) molecular hybrid offers a new platform featuring conformationally predetermined cofacial D-A orientation with a fixed edge-to-edge separation, REE (2.8 Å), without the aid of covalent bonds. Sub-picosecond PIET (τET ≤ 0.4 ps) and very slow charge recombination (τCR ≈ 600 ps) dynamics are observed. The origin of these dynamics is discussed in terms of enhanced D-A coupling (V = 675 cm-1) and extremely small reorganization energy (λ ≈ 0.18 eV), induced by the intrinsic structural rigidity of the C70@COP-5 complex.
RESUMO
Realizing chromophores that simultaneously possess substantial near-infrared (NIR) absorptivity and long-lived, high-yield triplet excited states is vital for many optoelectronic applications, such as optical power limiting and triplet-triplet annihilation photon upconversion (TTA-UC). However, the energy gap law ensures such chromophores are rare, and molecular engineering of absorbers having such properties has proven challenging. Here, we present a versatile methodology to tackle this design issue by exploiting the ethyne-bridged (polypyridyl)metal(II) (M; M = Ru, Os)-(porphinato)metal(II) (PM'; M' = Zn, Pt, Pd) molecular architecture (M-(PM')n-M), wherein high-oscillator-strength NIR absorptivity up to 850 nm, near-unity intersystem crossing (ISC) quantum yields (ΦISC), and triplet excited-state (T1) lifetimes on the microseconds time scale are simultaneously realized. By varying the extent to which the atomic coefficients of heavy metal d orbitals contribute to the one-electron excitation configurations describing the initially prepared singlet and triplet excited-state wave functions, we (i) show that the relative magnitudes of fluorescence (k0F), S1 â S0 nonradiative decay (knr), S1 â T1 ISC (kISC), and T1 â S0 relaxation (kT1âS0) rate constants can be finely tuned in M-(PM')n-M compounds and (ii) demonstrate designs in which the kISC magnitude dominates singlet manifold relaxation dynamics but does not give rise to T1 â S0 conversion dynamics that short-circuit a microseconds time scale triplet lifetime. Notably, the NIR spectral domain absorptivities of M-(PM')n-M chromophores far exceed those of classic coordination complexes and organic materials possessing similarly high yields of triplet-state formation: in contrast to these benchmark materials, this work demonstrates that these M-(PM')n-M systems realize near unit ΦISC at extraordinarily modest S1-T1 energy gaps (â¼0.25 eV). This study underscores the photophysical diversity of the M-(PM')n-M platform and presents a new library of long-wavelength absorbers that efficiently populate long-lived T1 states.
RESUMO
BACKGROUND: To determine whether the presence of intra-amniotic infection and elevated proinflammatory cytokine levels in amniotic fluid (AF) are associated with failure in the newborn hearing screen (NHS) test in very preterm neonates. METHODS: This is a retrospective cohort study of 112 premature singleton neonates born to women with preterm labor or preterm premature rupture of membranes at ≤32 wk. AF obtained through amniocentesis was cultured, and interleukin-6 (IL-6) and IL-8 levels were determined. RESULTS: Fourteen (12.5%) neonates failed the NHS test. The prevalence of a positive AF culture was 40% (45/112). Multiple logistic regression analyses indicated that intra-amniotic infection was significantly associated with failure in the NHS test after adjusting for baseline covariates such as maternal white blood cell count (WBC) and periventricular leukomalacia. However, the IL-6 and IL-8 levels in AF were not significantly associated with hearing screen failure. Moreover, neither gestational age at birth nor birth weight was associated with NHS failure. CONCLUSION: The presence of intra-amniotic infection, but not elevated levels of AF IL-6 and IL-8, may contribute to the risk for failure in the NHS test in very preterm neonates. This finding suggests that intra-amniotic infection in utero might contribute to the development of congenital sensorineural hearing loss.
Assuntos
Líquido Amniótico/microbiologia , Testes Auditivos , Interleucina-6/química , Interleucina-8/química , Triagem Neonatal/métodos , Complicações Infecciosas na Gravidez/diagnóstico , Amniocentese , Líquido Amniótico/química , Corioamnionite , Feminino , Idade Gestacional , Audição , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Inflamação , Interleucina-6/sangue , Interleucina-8/sangue , Leucomalácia Periventricular/sangue , Trabalho de Parto Prematuro , Gravidez , Análise de Regressão , Estudos Retrospectivos , Fatores de RiscoRESUMO
Being a member of the van der Waals class of solids, bilayer MoS2 exhibits polytypism due to different possible stacking arrangements, namely, 2Hc, 2Ha and 3R-polytypes. Unlike monolayer MoS2, these bilayers exhibit indirect band gaps. Band extrema states originate from a linear combination of Mo-(d) and S-(p) orbitals which are sensitive to the interlayer interactions. We have studied the impact of stacking pattern on the electronic structure and electron/hole transport properties of these polytypes. Based on first-principles computations coupled with the Boltzmann transport formalism, we found that a strong electron-hole anisotropy can be realised in the 2Ha-MoS2 polytype unlike in a monolayer which is isotropic in nature. A staggered arrangement between two layers results in a higher relaxation time for electrons compared to holes leading to anisotropy which is of importance in device engineering.
RESUMO
We report on electronically excited-state dynamics of three different trifluoromethyl C60 fullerenes (TMFs, C60(CF3)n: C60/4-1, C60/6-2, and C60/10-1, featuring four, six, and ten trifluoromethyl groups, respectively) using steady-state and time-resolved optical spectroscopy as well as ultrafast pump/probe transient absorption spectroscopy. C60/4-1 and C60/6-2 dissolved in toluene solvent show near-unity S1 â T1 intersystem crossing quantum yield (ΦISC), ca. 1 ns S1-state lifetimes, and microsecond-timescale T1-state lifetimes, which are typical of the fullerene class. On the other hand, C60/10-1 exhibits a dominant sub-nanosecond nonradiative S1 â S0 relaxation mechanism and negligible ΦISC, therefore decreasing the average excited-state lifetime (τavg) by about 5 orders of magnitude compared to that of C60/4-1 and C60/6-2 (τavg ≈ 17 µs and 54 µs for C60/4-1 and C60/6-2, respectively, whereas τavg ≈ 100 ps for C60/10-1). These excited-state characteristics of C60/4-1 and C60/6-2 are preserved in polymer matrix, suggesting that fullerene/polymer interactions do not modulate intrinsic photophysics of trifluoromethyl-substituted fullerenes. The contrasting excited-state study results of C60/4-1 and C60/6-2 to that of C60/10-1 infer that intrinsic optical properties and excited-state dynamics can be affected by the substitution on the fullerene.
RESUMO
Bisphenol A (BPA) is a high-volume industrial chemical used in the global production of polycarbonate plastics and epoxy resins, which are used in food and drink containers, such as tableware (plates and mugs). Due to its broad applications, BPA has been detected in human blood, urine and breast milk as well as environmental substances, including water, indoor and outdoor air, and dust. Indeed, exposure to high concentrations of BPA can result in a variety of harmful effects, including reproductive toxicity, through a mechanism of endocrine disruption. Our comparison of reported BPA urinary concentrations among different countries revealed that exposures in Korea may be higher than those in other Asian countries and North America, but lower than or similar to those in European countries. The current study included a total of 2044 eligible subjects of all ages. The subjects were evenly divided between males and females (48.58% and 51.42%, respectively). The geometric mean (GM) of pre-adjusted (adjusted) urinary BPA concentrations was 1.83µg/L (2.01µg/g creatinine) for subjects of all ages, and there was no statistically difference in BPA concentrations between males (1.90µg/L, 1.87µg/g creatinine) and females (1.76µg/L, 2.16µg/g creatinine). Multiple regression analysis revealed only one positive association between creatinine pre-adjusted urinary BPA concentration and age (ß=-0.0868, p<0.001). The 95th percentile levels of 24-hour recall (HR), food frequency questionnaires (FFQ) and estimated daily intake (EDI) through urinary BPA concentrations were 0.14, 0.13, and 0.22µg/kg bw/day, respectively. According to the Ministry of Food and Drug Safety (MFDS), a tolerable daily intake (tDI) of 20µg/kg bw/day was established for BPA from the available toxicological data. Recently, the European Food Safety Authority (EFSA) established a temporary TDI of 4µg/kg bw/day based on current toxicological data. By comparing these TDIs with subjects' exposure, we conclude that there are no health concerns for any age group as a result of current levels of dietary exposure to BPA.
Assuntos
Compostos Benzidrílicos/urina , Disruptores Endócrinos/urina , Poluentes Ambientais/urina , Fenóis/urina , Plastificantes/análise , Adolescente , Adulto , Criança , Pré-Escolar , Dieta , Monitoramento Ambiental , Feminino , Contaminação de Alimentos/análise , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , República da Coreia , Medição de Risco , Adulto JovemRESUMO
Benzophenone (BP) and its derivatives are widely used in various cosmetics, personal care products, and food packaging ink. The use of BP has raised concerns about the potential health risks associated with its endocrine-disrupting effects. This study evaluated urinary concentrations of BP derivatives in a national sample of the South Koreans population aged 6-89 years. From July to September in each 2010 and 2011, 1576 urine samples were collected. Urinary concentrations of benzophenone-1 (BP-1), benzophenone-2 (BP-2), benzophenone-3 (BP-3), benzophenone-4 (BP-4), benzophenone-8 (BP-8), and 4-hydroxybenzophenone (4-OH-BP) were analyzed using liquid chromatography-mass spectrometry. The detection rate for BP-1 and 4-OH-BP were 56% [limit of detection (LOD) 0.59ng/mL] and 88% (LOD 0.04ng/mL), respectively, whereas those for BP-2, BP-3, BP-4, and BP-8 were all below 25%. The geometric means of urinary BP-1 and 4-OH-BP concentrations were 1.24ng/mL and 0.45ng/mL, respectively. Multiple linear regression analysis indicated that concentrations of BP-1 in and of 4-OH-BP in adults were associated with sex and age. The BP-1 and 4-OH-BP concentration of children and adolescents was associated with sex, age, income, and current area of residence. The correlation was observed between urinary concentrations of BP derivatives, which is an important indication of exposure biomarkers and the metabolic pathways from BP-3. This is the first national study to evaluate the presence of BP derivatives in urine samples from the South Korean population, stratified by demographic factors.
Assuntos
Benzofenonas/urina , Disruptores Endócrinos/urina , Exposição Ambiental , Poluentes Ambientais/urina , Fatores Socioeconômicos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Disruptores Endócrinos/análise , Monitoramento Ambiental , Poluentes Ambientais/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , República da Coreia , Adulto JovemRESUMO
Parabens are broad-spectrum antimicrobial agents used in a range of consumer products, including personal care products, cosmetics, and food. Recently, the widespread use of parabens has raised concerns about the potential health risks associated with their endocrine-disrupting effect. In the present study, 2541 urine samples were collected and analyzed by liquid chromatography-mass spectrometry for the determination of the concentrations of methyl paraben (MeP), ethyl paraben (EtP), propyl paraben (PrP) and butyl paraben (BuP). The detection rate and geometric mean concentrations of parabens in the general population followed the order MeP (97.7%; 116ng/mL)>EtP (97.2%; 24.7ng/mL)>PrP (96.7%; 11.0ng/mL)>BuP (83.5%; 1.13ng/mL). The composition profiles showed that MeP and EtP accounted for >90% of the urinary paraben concentration. We performed statistical analysis in order to evaluate differences between demographic variables and urinary concentrations. Our results showed that adjusted proportional change of MeP, PrP, and BuP in adults were 2.67-6.13 times higher in females than in males. The urinary concentrations of PrP in adults increased significantly with age. The adjusted proportional changes of MeP and PrP in adults were associated with increased body mass index (BMI). The adjusted proportional changes of BuP and PrP in children and adolescents were 1.44 and 1.69 times higher in females than in males. However, there was no clear association between paraben concentrations and demographic variables in the children and adolescents groups. The estimated daily intake (EDIurine) of MeP and EtP in adults were 301µg/kg bw/day, which is lower than the acceptable daily intake (ADI; 10mg/kg bw/day). In summary, our results revealed that the general population in Korea was exposed to parabens during 2009-2010, and most Koreans are exposed to parabens. The urinary levels of parabens varied by age group with demographic factors in the Korean population. The results of study may be used to establish a nationally representative baseline of exposure to parabens in risk assessment.