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BACKGROUND: To evaluate the prognostic value of the pre-treatment aspartate transaminase (AST)/alanine transaminase (ALT) ratio in hepatocellular carcinoma (HCC) patients receiving radiofrequency ablation (RFA)/microwave ablation (MWA) combined with simultaneous TACE. METHODS: The data for 117 patients were retrospectively analyzed in this study. The endpoint of prognosis was overall survival (OS). The Youden index was used to choose the optimal cut-off value of the pre-treatment AST/ALT ratio for OS prediction. Univariate and multivariate analyses were used to identify independent risk factors, then integrated to establish the nomogram. RESULTS: The AST/ALT ratio cut-off value for OS prediction was 0.89, and patients with a higher AST/ALT ratio had poorer OS. The median OS for the high-value AST/ALT group was not reached, while the median OS for the low-value AST/ALT group was 48.5 months (P = 0.0047). The univariate and multivariate analysis showed that AST/ALT ratio, AFP, and tumor numbers were independent prognostic indicators for OS. The integrated nomogram showed higher predictive accuracy for OS (C-index 0.674, 95%CI: 0.600-0.748). CONCLUSIONS: The preoperative AST/ALT ratio could be a prognostic indicator for HCC patients receiving thermal ablation combined with simultaneous TACE.
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Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/patologia , Prognóstico , Alanina Transaminase , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Aspartato Aminotransferases , Resultado do TratamentoRESUMO
Infrared-to-visible photon upconversion could benefit applications such as photovoltaics, infrared sensing, and bioimaging. Solid-state upconversion based on triplet exciton annihilation sensitized by nanocrystals is one of the most promising approaches, albeit limited by relatively weak optical absorption. Here, we integrate the upconverting layers into a Fabry-Pérot microcavity with quality factor Q = 75. At the resonant wavelength λ = 980 nm, absorption increases 74-fold and we observe a 227-fold increase in the intensity of upconverted emission. The threshold excitation intensity is reduced by 2 orders of magnitude to a subsolar flux of 13 mW/cm2. We measure an external quantum efficiency of 0.06 ± 0.01% and a 2.2-fold increase in the generation yield of upconverted photons. Our work highlights the potential of triplet-triplet annihilation-based upconversion in low-intensity sensing applications and demonstrates the importance of photonic designs in addition to materials engineering to improve the efficiency of solid-state upconversion.
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Colloidal quantum dots (CQDs) are a promising gain material for solution-processed, wavelength-tunable lasers, with potential application in displays, communications, and biomedical devices. In this work, we combine a CQD film with an array of nanoantennas, made of titanium dioxide cylinders, to achieve lasing via bound states in the continuum (BICs). Here, the BICs are symmetry-protected cavity modes with giant quality factors, arising from slab waveguide modes in the planar CQD film, coupled to the periodic nanoantenna array. We engineer the thickness of the CQD film and size of the nanoantennas to achieve a BIC with good spatial and spectral overlap with the CQDs, based on a second-order transverse-electric (TE)-polarized waveguide mode. We obtain room-temperature lasing with a low threshold of approximately 11 kW/cm2 (peak intensity) under 5-ns-pulsed optical excitation. This work sheds light on the optical modes in solution-processed, distributed-feedback lasers and highlights BICs as effective, versatile, surface-emitting lasing modes.
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Solid-state room-temperature lasing with tunability in a wide range of wavelengths is desirable for many applications. To achieve this, besides an efficient gain material with a tunable emission wavelength, a high quality-factor optical cavity is essential. Here, we combine a film of colloidal CdSe/CdZnS core-shell nanoplatelets with square arrays of nanocylinders made of titanium dioxide to achieve optically pumped lasing at visible wavelengths and room temperature. The all-dielectric arrays support bound states in the continuum (BICs), which result from lattice-mediated Mie resonances and boast infinite quality factors in theory. In particular, we demonstrate lasing from a BIC that originates from out-of-plane magnetic dipoles oscillating in phase. By adjusting the diameter of the cylinders, we tune the lasing wavelength across the gain bandwidth of the nanoplatelets. The spectral tunability of both the cavity resonance and nanoplatelet gain, together with efficient light confinement in BICs, promises low-threshold lasing with wide selectivity in wavelengths.
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Background: Teleophthalmology programs are expanding, but have not been adapted into many emergency departments (EDs) in the United States. Introduction: Determining the potential demand for teleophthalmology services in the United States. EDs could enable development of new strategies to improve access to eye care in resource-limited regions. Methods: Telephone surveys were administered to ED physicians and nurses in Florida. Perceptions of ophthalmologist availability, equipment availability, and perceived utility of teleophthalmology services were measured. Results: Responses were from 104 of 207 facilities (50.2%); 88/181 (48.6%) designated as nonrural hospitals (NRHs) and 16/26 (61.5%) as rural hospitals (RHs). NRHs reported a median of 1 ophthalmologist available on call compared with a median of 0 at RHs (p < 0.001). NRHs were more likely to have a slit lamp (98.9% NRH, 50.0% RH; p < 0.001) and tonometer (100% NRH, 75.0% RH; p < 0.001). On a scale from 1 (lowest) to 5, most (68/93; 73.1%) perceived the value of teleophthalmology for remote consults as a 4 or 5. The most common perceived benefit of teleophthalmology use was to provide second/expert opinion (26.5% of responses). The most commonly cited perceived disadvantage was the physical unavailability of an ophthalmologist for examination and follow-up care (35.5% of responses). Discussion: RHs have less access to ophthalmologists and ophthalmic equipment when managing eye-related complaints in the ED. At both RHs and NRHs, providers face limitations in managing eye complaints and perceived teleophthalmology as a potentially valuable tool for remote expert consultation. Conclusions: Results suggest teleophthalmology services may be used to improve access to expert ophthalmic care, particularly in rural communities.
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Oftalmologia , Consulta Remota , Telemedicina , Serviço Hospitalar de Emergência , Florida , Humanos , Estados UnidosRESUMO
PURPOSE: To evaluate the ability of OCT optic nerve head (ONH) and macular parameters to detect disease progression in eyes with advanced structural glaucomatous damage of the circumpapillary retinal nerve fiber layer (cRNFL). DESIGN: Longitudinal study. PARTICIPANTS: Forty-four eyes from 37 patients with advanced average cRNFL damage (≤60 µm) followed up for an average of 4.0 years. METHODS: All patients were examined with spectral-domain OCT and visual field (VF) assessment during at least 4 visits. MAIN OUTCOME MEASUREMENTS: Visual field mean deviation (MD) and VF index. OCT cRNFL (average, superior, and inferior quadrants), ganglion cell-inner plexiform layer (GCIPL) (average, superior, and inferior), rim area, cup volume, average cup-to-disc (C:D) ratio, and vertical C:D ratio. RESULTS: At baseline, patients had a median VF MD of -10.18 dB and mean cRNFL of 54.55±3.42 µm. The rate of change for MD and VF index were significant. No significant rate of change was noted for cRNFL, whereas significant (P < 0.001) rates were detected for GCIPL (-0.57±0.05 µm/year) and ONH parameters such as rim area (-0.010±0.001 mm2/year). CONCLUSIONS: Macula GCIPL and ONH parameters may be useful in tracking progression in patients with advanced glaucoma.
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Glaucoma de Ângulo Aberto/diagnóstico , Macula Lutea/patologia , Fibras Nervosas/patologia , Disco Óptico/patologia , Doenças do Nervo Óptico/diagnóstico , Células Ganglionares da Retina/patologia , Idoso , Progressão da Doença , Feminino , Seguimentos , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Pressão Intraocular/fisiologia , Macula Lutea/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Disco Óptico/diagnóstico por imagem , Doenças do Nervo Óptico/fisiopatologia , Tomografia de Coerência Óptica , Acuidade Visual/fisiologia , Testes de Campo Visual , Campos Visuais/fisiologiaRESUMO
PURPOSE: Previously, we introduced a state-based 2-dimensional continuous-time hidden Markov model (2D CT HMM) to model the pattern of detected glaucoma changes using structural and functional information simultaneously. The purpose of this study was to evaluate the detected glaucoma change prediction performance of the model in a real clinical setting using a retrospective longitudinal dataset. DESIGN: Longitudinal, retrospective study. PARTICIPANTS: One hundred thirty-four eyes from 134 participants diagnosed with glaucoma or as glaucoma suspects (average follow-up, 4.4±1.2 years; average number of visits, 7.1±1.8). METHODS: A 2D CT HMM model was trained using OCT (Cirrus HD-OCT; Zeiss, Dublin, CA) average circumpapillary retinal nerve fiber layer (cRNFL) thickness and visual field index (VFI) or mean deviation (MD; Humphrey Field Analyzer; Zeiss). The model was trained using a subset of the data (107 of 134 eyes [80%]) including all visits except for the last visit, which was used to test the prediction performance (training set). Additionally, the remaining 27 eyes were used for secondary performance testing as an independent group (validation set). The 2D CT HMM predicts 1 of 4 possible detected state changes based on 1 input state. MAIN OUTCOME MEASURES: Prediction accuracy was assessed as the percentage of correct prediction against the patient's actual recorded state. In addition, deviations of the predicted long-term detected change paths from the actual detected change paths were measured. RESULTS: Baseline mean ± standard deviation age was 61.9±11.4 years, VFI was 90.7±17.4, MD was -3.50±6.04 dB, and cRNFL thickness was 74.9±12.2 µm. The accuracy of detected glaucoma change prediction using the training set was comparable with the validation set (57.0% and 68.0%, respectively). Prediction deviation from the actual detected change path showed stability throughout patient follow-up. CONCLUSIONS: The 2D CT HMM demonstrated promising prediction performance in detecting glaucoma change performance in a simulated clinical setting using an independent cohort. The 2D CT HMM allows information from just 1 visit to predict at least 5 subsequent visits with similar performance.
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Glaucoma/diagnóstico , Pressão Intraocular/fisiologia , Disco Óptico/patologia , Células Ganglionares da Retina/patologia , Tomografia de Coerência Óptica/métodos , Acuidade Visual , Campos Visuais/fisiologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Valor Preditivo dos Testes , Estudos Prospectivos , Estudos Retrospectivos , Fatores de TempoRESUMO
AIM: To validate the prognostic value of lactic dehydrogenase to albumin ratio (LAR) in patients with unresectable pancreatic cancer treated by intervention chemotherapy. MATERIALS & METHODS: There were 139 patients retrospectively analyzed in this study. The survival was depicted with Kaplan-Meier curves and calculated by log-rank test. We used Cox proportional hazards regression model with univariate and multivariate analyses, and integrated all independent risk factors to establish the nomogram. RESULTS: Patient with higher LAR group had poorer overall survival (OS). The Tumor, Node, Metastasis stage, carcinoembryonic antigen and LAR have been shown to be independent prognostic indicators for OS. The nomogram indicated superior predictive accuracy for OS. CONCLUSION: The preoperative LAR can be a prognostic indicator for unresectable pancreatic cancer patients with interventional therapy.
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Antineoplásicos/uso terapêutico , L-Lactato Desidrogenase/sangue , Neoplasias Pancreáticas/sangue , Albumina Sérica/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígeno Carcinoembrionário/sangue , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Nomogramas , Cuidados Paliativos/métodos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Período Pré-Operatório , Prognóstico , Estudos Retrospectivos , Resultado do TratamentoRESUMO
The adaptive coordination of trust services can provide highly dependable and personalized solutions for industrial requirements in the service-oriented industrial internet of things (IIoT) architecture to achieve efficient utilization of service resources. Although great progress has been made, trust service coordination still faces challenging problems such as trustless industry service, poor coordination, and quality of service (QoS) personalized demand. In this paper, we propose a QoS-driven and adaptive trust service coordination method to implement Pareto-efficient allocation of limited industrial service resources in the background of the IIoT. First, we established a Pareto-effective and adaptive industrial IoT trust service coordination model and introduced a blockchain-based adaptive trust evaluation mechanism to achieve trust evaluation of industrial services. Then, taking advantage of a large and complex search space for solution efficiency, we introduced and compared multi-objective gray-wolf algorithms with the particle swarm optimization (PSO) and dragonfly algorithms. The experimental results showed that by judging and blacklisting malicious raters quickly and accurately, our model can efficiently realize self-adaptive, personalized, and intelligent trust service coordination under the given constraints, improving not only the response time, but also the success rate in coordination.
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Water decontamination from As(III) is an urgent but still challenging task. Herein, we fabricated a bifunctional nanocomposite HFO@PS-Cl for highly efficient removal of As(III), with active chlorine covalently binding spherical polystyrene host for in situ oxidation of As(III) to As(V), and Fe(III) hydroxide (HFO) nanoparticles (NPs) embedded inside for specific As(V) removal. HFO@PS-Cl could work effectively in a wide pH range (5-9), and other substances like sulfate, chloride, bicarbonate, silicate, and humic acid exert insignificant effect on As(III) removal. As(III) sequestration is realized via two pathways, that is, oxidation to As(V) by the active chlorine followed by specific As(V) adsorption onto HFO NPs, and As(III) adsorption onto HFO NPs followed by oxidation to As(V). The exhausted HFO@PS-Cl could be refreshed for cyclic runs with insignificant capacity loss by the combined regeneration strategy, that is, alkaline solution to rinse the adsorbed As(V) and NaClO solution to renew the host oxidation capability. In addition, fixed-bed experiments demonstrated that the HFO@PS-Cl column could generate >1760 bed volume (BV) effluent from a synthetic As(III)-containing groundwater to meet the drinking water standard (<10 µg As/L), whereas other two HFO nanocomposites, HFO@PS-N and HFO@D201 could only generate 450 and 600 BV effluents under otherwise identical conditions.
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Compostos Férricos , Nanocompostos , Poluentes Químicos da Água , Purificação da Água , Adsorção , Arsênio , Oxirredução , Polímeros , ÁguaRESUMO
BACKGROUND: Heart failure (HF) patients have a high incidence of new-onset AF. Given the adverse prognostic influence of AF in HF, identifying patients at high risk of developing AF is important. METHODSâANDâRESULTS: The incidence and factors associated with new-onset AF were investigated in patients in sinus rhythm with reduced LVEF enrolled in the Warfarin versus Aspirin in Reduced Cardiac Ejection Fraction (WARCEF) trial. Analyses involved clinical factors alone (n=2,219), and clinical plus echocardiographic findings (n=1,125). During 3.5±1.8 years of follow-up, 212 patients (9.6% of total cohort) developed AF. In both samples, new-onset AF was associated with age, male sex, White race, and IHD. Among echocardiographic variables, only LAD predicted AF. On multivariate Cox modeling, age (HR, 1.02; 95% CI: 1.00-1.03, P=0.008), IHD (HR, 1.37; 95% CI: 1.02-1.84, P=0.036) and LAD (HR, 1.48; 95% CI: 1.15-1.91, P=0.003) remained associated with AF onset. Patients with IHD, LAD>4.5 cm and age>50 years had a 2.5-fold higher risk of AF than patients without any of these characteristics (HR, 2.52; 95% CI: 1.72-3.69, P<0.0001). CONCLUSIONS: Age, IHD and LAD independently predict new-onset AF in HF patients in sinus rhythm, at younger age and smaller LAD than generally believed. This information may be useful to risk-stratify HF patients for AF development, allowing close monitoring and possibly early detection. (Circ J 2016; 80: 619-626).
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Aspirina/administração & dosagem , Fibrilação Atrial , Ecocardiografia , Insuficiência Cardíaca , Varfarina/administração & dosagem , Fatores Etários , Idoso , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/etiologia , Fibrilação Atrial/fisiopatologia , Seguimentos , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Humanos , Pessoa de Meia-Idade , Volume Sistólico/efeitos dos fármacosRESUMO
Triplet excitons are ubiquitous in organic optoelectronics, but they are often an undesirable energy sink because they are spin-forbidden from emitting light and their high binding energy hinders the generation of free electron-hole pairs. Harvesting their energy is consequently an important technological challenge. Here, we demonstrate direct excitonic energy transfer from 'dark' triplets in the organic semiconductor tetracene to colloidal PbS nanocrystals, thereby successfully harnessing molecular triplet excitons in the near infrared. Steady-state excitation spectra, supported by transient photoluminescence studies, demonstrate that the transfer efficiency is at least (90 ± 13)%. The mechanism is a Dexter hopping process consisting of the simultaneous exchange of two electrons. Triplet exciton transfer to nanocrystals is expected to be broadly applicable in solar and near-infrared light-emitting applications, where effective molecular phosphors are lacking at present. In particular, this route to 'brighten' low-energy molecular triplet excitons may permit singlet exciton fission sensitization of conventional silicon solar cells.
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OBJECTIVES: Congenital diaphragmatic hernia (CDH) survivors often have gastrointestinal disorders, and limited outcome data exist. This study reviewed risk factors for low weight and use of feeding tubes after CDH repair at 1 year of age. The hypothesis was that patients who required extracorporeal membrane oxygenation (ECMO) or with significant pulmonary arterial hypertension (PAH) would have lower weight percentiles and more often require tube feedings. METHODS: A retrospective chart review of 89 infants with CDH diagnosed in the neonatal period was conducted. Statistical analysis was performed using χ test, Fisher exact test, and logistic regression. RESULTS: Seventy-two patients (81%) survived to 1 year of age. Of these patients, 35% were <5th percentile for weight and 18% were receiving tube feedings. Both ECMO and PAH were associated with an increased risk for requiring tube feedings at 1 year of age, with respective odds ratios of 6.00 (P = 0.01) and 15.75 (P = 0.02); however, neither ECMO nor PAH was associated with low weight at 1 year of age. No statistical correlation was found between an abnormal pH probe and tube feedings at 1 year of age. CONCLUSIONS: Patients with CDH are at increased risk for having a weight <5th percentile at 1 year of age. A history of ECMO and PAH are independently associated with an increased requirement for tube feedings at 1 year of age. Close nutritional monitoring and counseling should be considered in all of the patients with CDH, particularly those with a history of ECMO or PAH.
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Nutrição Enteral , Transtornos do Crescimento/etiologia , Hérnia Diafragmática/complicações , Hérnias Diafragmáticas Congênitas/complicações , Magreza/etiologia , Oxigenação por Membrana Extracorpórea , Feminino , Hérnia Diafragmática/terapia , Hérnias Diafragmáticas Congênitas/terapia , Humanos , Lactente , Modelos Logísticos , Masculino , Razão de Chances , Prevalência , Estudos Retrospectivos , Fatores de Risco , Taxa de Sobrevida , Magreza/epidemiologiaRESUMO
Sodium p-perfluorous nonenoxybenzene sulfonate (OBS)-one of the main alternatives to perfluorooctane sulfonate-has been increasingly detected in both aquatic environments and human bodies. Therefore, the pathogenic risks of OBS exposure warrant attention, especially its central nervous system toxicity mechanism under long-term exposure. In this study, the effects and mechanisms of OBS on the zebrafish brain at 40 days post exposure were examined. The results demonstrated that at 3.2 µg/L, OBS had no significant effect on the zebrafish brain, but 32 µg/L OBS caused depression or poor social behavior in zebrafish and reduced both their memory and survival ability. These changes were accompanied by histological damage and cell apoptosis. Furthermore, OBS caused the accumulation of excessive reactive oxygen species in the fish brain, leading to oxidative stress and subsequently cell apoptosis. Moreover, an imbalance of both inflammatory factors (IL-6, IL-1ß, IL-10, TNF-α, and NF-κB) and neurotransmitters (GABA and Glu) led to neuroinflammation. Additionally, 32 µg/L OBS induced decreases in mitochondrial membrane potential and Na+-K+-ATPase activity, leading to both mitochondrial structural damage and the emergence of mitochondrial autophagosomes, partly explaining the neurotoxicity of OBS. These results help to analyze the target sites and molecular mechanisms of OBS neurotoxicity and provide a basis for the scientific evaluation of its health risks to humans.
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Apoptose , Fluorocarbonos , Mitocôndrias , Estresse Oxidativo , Poluentes Químicos da Água , Peixe-Zebra , Animais , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Poluentes Químicos da Água/toxicidade , Fluorocarbonos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Síndromes Neurotóxicas , ATPase Trocadora de Sódio-Potássio/metabolismo , Ácidos Alcanossulfônicos/toxicidadeRESUMO
To address the low-carbon treatment requirements for municipal wastewater, a novel anaerobic acidification membrane bioreactor (AAMBR) was developed for recovering organic matter in terms of volatile fatty acids (VFAs). While the AAMBR successfully generated VFAs from municipal wastewater through forward osmosis (FO) membrane concentration, its operation was limited to a single pH value of 10.0. Here, performance of the AAMBR operating at acidic condition was evaluated and compared with that at alkaline condition. The findings revealed that the AAMBR with pH 5.0 efficiently transformed organic matter into acetic acid, propionic acid, and butyric acid, resulting in a VFAs yield of 0.48 g/g-CODfeed. In comparison with the AAMBR at pH 10.0, this study achieved a similar VFAs yield, a lower fouling tendency, a lower loss of nutrients and a lower controlling cost. In conclusion, this study demonstrated that a pH of 5.0 is optimal for the AAMBR treating municipal wastewater.
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Reatores Biológicos , Águas Residuárias , Anaerobiose , Ácidos Graxos Voláteis , Concentração de Íons de Hidrogênio , Membranas ArtificiaisRESUMO
Learning about the strain/stress distribution in a material is essential to achieve its mechanical stability and proper functionality. Conventional techniques such as universal testing machines only apply to static samples with standardized geometry in laboratory environment. Soft mechanical sensors based on stretchable conductors, carbon-filled composites, or conductive gels possess better adaptability, but still face challenges from complicated fabrication process, dependence on extra readout device, and limited strain/stress mapping ability. Inspired by the camouflage mechanism of cuttlefish and chameleons, here an innovative responsive hydrogel containing light-scattering "mechano-iridophores" is developed. Force induced reversible phase separation manipulates the dynamic generation of mechano-iridophores, serving as optical indicators of local deformation. Patch-shaped mechanical sensors made from the responsive hydrogel feature fast response time (<0.4 s), high spatial resolution (≈100 µm), and wide dynamic ranges (e.g., 10-150% strain). The intrinsic adhesiveness and self-healing material capability of sensing patches also ensure their excellent applicability and robustness. This combination of chemical and optical properties allows strain/stress distributions in target samples to be directly identified by naked eyes or smartphone apps, which is not yet achieved. The great advantages above are ideal for developing the next-generation mechanical sensors toward material studies, damage diagnosis, risk prediction, and smart devices.
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PURPOSE: Calf muscles play an important role in marathon race, and the incidence of injury is high in this process. This study prospectively quantified diffusion tensor metrics, muscle fat fraction (MFF) and cross-sectional area (CSA) of calf muscles induced by endurance exercise in amateur marathoners, and the potential mechanisms underlying the changes in these parameters were analyzed. METHOD: In this prospective study, 35 marathoners (27 males, 8 females; mean age (standard deviation, SD), 38.92 (4.83) years) and 26 controls (18 males, 8 females; mean age (SD), 38.35 (6.75) years) underwent magnetic resonance imaging (MRI) from September 2022 to March 2023. The diffusion tensor eigenvalues (λ1, λ2, λ3), radial diffusivity (RD), fractional anisotropy (FA), MFF and CSA of calf muscles were compared between marathoners and controls. A binary logistic regression model with gender correction was performed analyze the relationship between marathon exercise and DTI parameters, CSA and MFF of calf muscles. RESULTS: Interobserver agreement was good (κ = 0.71). The results of binary logistic regression model with gender correction showed that the regression coefficients of FA values in anterior group of calf (AC), soleus (SOL), medial gastrocnemius (MG) and lateral gastrocnemius (LG) were negative, and the odds ratios (OR) were 0.33, 0.45, 0.35, 0.05, respectively (P < 0.05). The OR of RD in SOL and λ2 in external group of calf (EC) were relatively higher, 3.74 and 3.26, respectively (P < 0.05). CSA was greater in SOL of marathoners, with an OR value of 1.00(P < 0.05). The MFF in AC and LG was lower in marathoners and OR of two indexes were -0.69 and -0.59, respectively (P < 0.05). CONCLUSIONS: Diffusion tensor imaging (DTI) combined with chemical shift-encoded sequence can noninvasively detect and quantify the adaptive changes of calf muscle morphology, microstructure and tissue composition induced by long-term running training in amateur marathoners.
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Imagem de Tensor de Difusão , Corrida de Maratona , Músculo Esquelético , Humanos , Imagem de Tensor de Difusão/métodos , Masculino , Feminino , Músculo Esquelético/diagnóstico por imagem , Adulto , Estudos Prospectivos , Corrida de Maratona/fisiologia , Perna (Membro)/diagnóstico por imagem , Adaptação FisiológicaRESUMO
Objective: To investigate the accuracy of calcicum supression (CaSupp) technique derived from double-layer detector spectral computed tomography (DSCT) in the diagnosis of traumatic bone marrow edema in the knee. Methods: Twenty-three patients with trauma in the knee who underwent DSCT and Magnetic Resonance Imaging (MRI) in the Third Hospital of Hebei Medical University from October 2021 to March 2022 were retrospectively collected. To make the evaluation more detailed and accurate, each knee was divided into 10 partitions. Bone marrow edema in each partition of the knee was evaluated by two physicians (physician A and B) using CaSupp images combined with conventional CT-CaSupp fusion false-color images. MRI results were used as the gold standard and the accuracy of the CaSupp technique was analyzed in the diagnosis of traumatic bone marrow edema in the knee. The CaSuppCT values of the normal bone marrow area and the bone marrow edema area were delineated, and receiver operating curve (ROC curve) was drawn to find the optimal cut-off value of CaSuppCT as the quantitative parameter for the diagnosis of bone marrow edema. Results: The diagnostic sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of physician A were 83.1 %, 98.1 %, 95.5 % and 92.1 %, respectively; those of physician B were 93.5 %, 97.4 %, 94.7 % and 96.8 %, respectively. The CaSuppCT values in the bone marrow edema areas were higher than those in the normal areas, and the difference was statistically significant. The area under the receiver operating characteristic curve (AUC) of the CaSuppCT values was 0.979, and the cut-off value was 7.05Hu*. The corresponding diagnostic sensitivity was 87.0 %, and specificity was 100.0 %. Conclusion: The CaSupp technique derived from DSCT has high sensitivity and specificity in the detection of traumatic bone marrow edema in the knee, and can provide more imaging information for clinical practice.
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Owing to high water content and homogeneous texture, conventional hydrogels hardly reach satisfactory mechanical performance. Tensile-resistant groups and structural heterogeneity are employed to fabricate tough hydrogels. However, those techniques significantly increase the complexity and cost of material synthesis, and have only limited applicability. Here, it is shown that ultra-tough hydrogels can be obtained via a unique hierarchical architecture composed of chemically coupled self-assembly units. The associative energy dissipation among them may be rationally engineered to yield libraries of tough gels with self-healing capability. Tunable tensile strength, fracture strain, and toughness of up to 19.6 MPa, 20 000%, and 135.7 MJ cmâ»3 are achieved, all of which exceed the best known records. The results demonstrate a universal strategy to prepare desired ultra-tough hydrogels in predictable and controllable manners.
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While sludge bulking often occurring in activated sludge processes generally leads to serious membrane fouling in membrane bioreactors (MBR), the underlying causes are still unclear. In this study, fouling behaviors of a MBR operated at stages of normal and sludge bulking were compared, and the fouling mechanisms of the different behaviors were explored. It was found that, the MBR could be stably operated in normal stage without membrane cleaning for about 60 days, whereas, daily membrane cleaning had to be carried out when operated in sludge bulking stage. The bulking sludge possessed a rather high specific filtration resistance (SFR) of about 1.36×1014 m·kg-1, which is over 5.33 times than that of the normal sludge. A series of characterizations demonstrated that the bulking sludge had rather lower dewaterability, smaller particle size, higher fractal dimension, higher viscosity, abundant filamentous bacteria and different functional groups of extracellular polymer sustains (EPS). It was suggested that microbial community transition was responsible for the occurrence of sludge bulking, further affecting membrane fouling. Based on these characterizations, it was reported that adhesion propensity (indicated by the thermodynamic interaction) of the bulking sludge to the membrane surface is about 3.6 times than that of the normal sludge. It was proposed that, extra force should be provided to offset a chemical potential gap caused by foulant layer structure transition during sludge bulking in order to sustain filtration of the bulking sludge, resulting in extremely high SFR. This study offered deep thermodynamic mechanisms of MBR fouling during occurrence of sludge bulking.