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To reduce fossil fuel consumption, blending sludge pyrolysis gas and ammonia (NH 3) for combustion enables the energy utilization of sludge pyrolysis gas while improving combustion characteristics of NH 3. This study employs chemiluminescence to investigate the structure of sludge pyrolysis gas/ammonia/air flame for the first time. A thorough investigation was conducted into the impacts of various swirl structure parameters on the stable combustion range and pollutant emissions. To further reduce pollutant emissions, staged combustion was used, and the effects of ammonia doping ratio, secondary air equivalence ratio, and secondary air inlet height on pollutant emissions were analyzed. The findings demonstrate that increasing the ammonia ratio narrows stable combustion equivalence ratio range. Additionally, at a thermal power of 5 kW, stable combustion was observed in the equivalence ratio range of 0.41–1.70, an improvement of 95.5%. Notably, staged combustion significantly reduced NO emissions, achieving concentrations as low as 32.7 ppm under stoichiometric conditions, compared to 1912.6 ppm in non-staged pure NH 3 combustion. This study provides valuable insights into the stability and emission characteristics of sludge pyrolysis gas/ammonia swirl burners for efficient and cleaner low-carbon fuels utilization. • First study on the stability and emissions of pyrolysis gas/NH 3 swirling flames. • Ammonia addition reduces OH* radiation intensity, particularly in lean combustion. • Increasing ammonia narrows the stable combustion equivalence ratio. • The optimal swirl parameters for stable combustion are proposed. • Staged combustion at 150 mm height reduces NO emissions to 32.7 ppm. [ABSTRACT FROM AUTHOR]

Accurate prediction neoadjuvant chemotherapy (NACT) response in ovarian cancer (OC) is essential for personalized medicine. We aimed to develop and validate a deep learning (DL) model based on pretreatment contrast-enhanced CT (CECT) images for predicting NACT responses and classifying high-grade serous ovarian cancer (HGSOC) to identify patients who may benefit from NACT. This multicenter study, which contained both retrospective and prospective studies, included consecutive OC patients (n = 757) from three hospitals. Using WHO RECIST 1.1 for the reference standard, a total of 587 women with 1761 images were included in the training and validation sets, 67 women with 201 images were included in the prospective sets, and 103 women with 309 images were included in the external sets. A multitask DL model based on the multiperiod CT image was developed to predict NACT response and HGSOC. Logistic regression analysis showed that peritoneal invasion, retinal invasion, and inguinal lymph node metastasis were independent predictors. The DL achieved promising segmentation performances with DICE mean = 0.83 (range: 0.78-0.87). For predicting NACT response, the DL model combined with clinical risk factors obtained area under the receiver operating characteristic curve (AUCs) of 0.87 (0.83-0.89), 0.88 (0.86-0.91), 0.86 (0.82-0.89), and 0.79 (0.75-0.82) in the training, validation, prospective, and external sets, respectively. The AUCs were 0.91 (0.87-0.94), 0.89 (0.86-0.91), 0.80 (0.76-0.84), and 0.80 (0.75-0.85) in four sets in HGSOC classification. The multitask DL model developed using multiperiod CT images exhibited a promising performance for predicting NACT response and HGSOC with OC, which could provide valuable information for individualized treatment. [ABSTRACT FROM AUTHOR]

Brain trauma can activate an attenuation of connexin gap junction that is implicated in neuronal injury, but the underlying cellular mechanisms remain incompletely understood. Here, we aimed to study whether autophagy, a stress-response process for recycling of intracellular proteins and organelles, is involved in the reduction of connexin 40 (Cx40) during the late phase of traumatic brain injury (TBI). In a rat model of TBI induced by controlled cortical impact (CCI), we found that Cx40 protein in the brain started to decline at post-surgery day 2 and the decrease continued for up to day 6. Such a relatively late response of Cx40 following TBI was found to be coincident with the substantial induction of neuron degeneration and autophagy, elevated autophagic vacuole numbers, and induced LC3-II and p62 levels. At day 4 post-injury, the extent of co-localization between LC3 and Cx40 was greatly enhanced, and the reduction of Cx40 was rescued by the administration of an autophagy inhibitor chloroquine. Thus, autophagy stimulated in the injured brains may act as a suppressing mechanism to decrease gap junction protein Cx40 in the late phase of TBI. [ABSTRACT FROM AUTHOR]

A three-dimensional probability of detection (POD) model integrating the depth, circumferential angle, and location of pipe wall thinning (PWT) was proposed for the probabilistic analysis of long-range pipe inspection using microwaves. Microwaves in TM 01 mode were used to detect PWT with different sizes and locations (up to 13.5 m). The microwave signals reflected from the PWT were measured and processed, and their amplitudes were extracted and treated as the signal response. The results showed that the signal response was rarely influenced by the axial length of the PWT, while its natural logarithm was proportional to the natural logarithm of the PWT depth and circumferential angle. In addition, the signal response decreased exponentially with the PWT location. Subsequently, a multivariate regression model was established, and the related coefficients were estimated using the maximum likelihood method. The POD calculated from the regression model suggests that a small PWT at a far distance (e.g., 36.0 m) can be reliably detected using microwaves. Compared with a two-dimensional POD model that considers only the PWT cross-section area as the size parameter, the proposed POD model clearly shows that the POD is more dependent on the circumferential angle than on the depth of the PWT. [ABSTRACT FROM AUTHOR]

The hydrogen adsorption capacity on β-cyclodextrin and the changes of adsorption influenced by titanium have been investigated through multiscale theoretical approach. The results show that, in the pristine β-cyclodextrin, hydrogen molecules intend to accumulate at the area outside edge of β-cyclodextrin. However, when β-cyclodextrin is modified by titanium, the accumulated fields of hydrogen molecules are changed. Furthermore, the calculations show that the frontier orbitals of β-cyclodextrin are evidently delocalized and the adsorption energy between β-cyclodextrin and hydrogen are enlarged for Ti modifying β-cyclodextrin. [ABSTRACT FROM AUTHOR]

This paper presents a multivariate probability of detection (POD) analysis method for long-range pipe inspection using microwave non-destructive testing (NDT). The proposed two-dimensional (2D) POD model considers both the size and location of pipe wall thinning (PWT) and is thus able to simultaneously characterize the detectability and detection range. First, the propagation of microwaves in a pipe with PWT was modeled through numerical simulation. The simulated S-parameters (S11) were converted into the time domain and were further processed to correlate the amplitude of the reflection signal with the corresponding PWT depth and location. The simulation results indicate that the logarithmic amplitude of the reflection signal is proportional to the PWT location and logarithmic PWT depth. Therefore, a prior multivariate regression model was established for the above three parameters. Second, an experiment was performed using a 14.5-m-long brass pipe. Twelve short pipes with six different inner diameters were used to emulate PWT and were deployed at eight different locations in the pipe. The experimental results suggest that each PWT can be detected with excellent repeatability, and show consistency with the simulation results. The processed experimental signals were subsequently employed for the regression model of the amplitude of the reflection signal, PWT depth, and location. Finally, a 2D POD model was constructed on the basis of the regression model and a dynamic-static threshold, combining in-pipe microwave signal attenuation with instrumental noises. The POD plot and contour give reasonable interpretations of the detection capability of this testing method against PWTs with different depths, considering the PWT locations. [ABSTRACT FROM AUTHOR]

Acute ischemic stroke is one of the main causes of mortality and morbidity worldwide. The present study aimed to explore the effects of exogenous insulin-like growth factor 1 (IGF-1) on the cognitive injuries induced by acute ischemic stroke and the underlying mechanisms. Acute ischemic stroke rat model was established via transient occlusion of the left middle cerebral artery to male Sprague-Dawley rats. IGF-1 was administered intravenously every other day 24 h after surgery for 14 days. Cognitive functions were determined by Morris water maze assay. Cerebral infarction and edema were determined by riphenyltetrazolium chloride staining and cerebral water content measurement. ELISA and Western blot were performed to detect concentrations of target proteins. Ischemic stroke rats exhibited reduced plasma IGF-1 level and impaired cognitive functions. Intravenous IGF-1 delivery increased the IGF-1 levels in plasma, ischemic amygdala, hippocampus and cortex, improved the neurological dysfunction, cognitive deficits, cerebral infarction and brain edema. Furthermore, IGF-1 relieved the systemic and cerebral inflammatory response by inhibiting the secretion of pro-inflammatory cytokines, interleukin (IL)-6, IL-1β, and tumor necrosis factor alpha (TNF-α), in serum and ischemic hippocampus of ischemic rats. Additionally, IGF-1 attenuated tau phosphorylation in ischemic hippocampus. In short, intravenous IGF-1 administration attenuates acute ischemic stroke-induced cognitive injuries in the experimental rat model possibly via modulating inflammatory response and tau phosphorylation, and might be of promising therapeutic value to ischemic stroke in the future. [ABSTRACT FROM AUTHOR]

Ammonia (NH 3) has been gaining popularity as a carbon-free alternative fuel in recent years. OH∗ chemiluminescence is a promising method to study the structure of ammonia flames, but research on this aspect is still lacking. In this study, the OH∗ chemiluminescence distributions and structure characteristics in NH 3 /H 2 and NH 3 /cracked gas swirl flames are experimentally investigated. The OH∗ distributions of NH 3 /H 2 and NH 3 /cracked gas under different addition levels and equivalence ratios are compared. The results show that the increase of equivalence ratio and hydrogen doping level significantly increased the OH∗ chemiluminescence peak of NH 3 /air swirling flame. Especially in fuel-lean flames, the equivalence ratio effect is greater than the NH 3 dilution effect, while the two effects are comparable in equivalence and fuel-rich conditions. The stretching effect of NH 3 /cracked gas is stronger, and the flame width is narrower than that of NH 3 /H 2 flame, but the peak value of OH∗ radiation is higher. • Profiles of OH∗chemiluminescence in NH 3 /H 2 swirling flame are visualized. • The intensity of the OH∗ peak increases as φ and X NH3 increase. • The φ effect dominates the increase of OH∗ intensity during lean combustion. • Partially cracked NH 3 /air flame OH∗ chemiluminescence are investigated. [ABSTRACT FROM AUTHOR]

Conductive polymers with high near-infrared absorbance, have attracted considerable attention in the design of intelligent nanomedicines for cancer therapy, especially chemo-photothermal therapy. However, the unknown long-term biosafety of conductive polymers in vivo due to non-degradability hinders their clinic application. Herein, a H 2 O 2 -triggered degradable conductive polymer, polyacrylic acid (PAA) stabilized poly(pyrrole-3-COOH) (PAA@PPyCOOH), is fabricated to form nanoparticles with doxorubicin (DOX) for safe and precise chemo-phototherapy. The PAA@PPyCOOH was found to be an ideal photothermal nano-agent with good dispersity, excellent biocompatibility and high photothermal conversion efficiency (56%). After further loading of doxorubicin (DOX), PAA@PPyCOOH@DOX demonstrates outstanding photothermal performance, as well as pH/H 2 O 2 dual-responsive release of DOX in tumors with an acidic and overexpressed H 2 O 2 microenvironment, resulting in superior chemo-photothermal therapeutic effects. The degradation mechanism of PAA@PPyCOOH is proposed to be the ring-opening reaction between the pyrrole-3-COOH unit and H 2 O 2. More importantly, the nanoparticles can be specifically degraded by excess H 2 O 2 in tumor, and the degradation products were confirmed to be excreted via urine and feces. In vivo therapeutic evaluation of chemo-photothermal therapy reveals tumor growth of 4T1 breast cancer model is drastically inhibited and no apparent side-effect is detected, thus indicating substantial potential in clinic application. [ABSTRACT FROM AUTHOR]

A novel (0.67- x)BiFeO 3 -0.33BaTiO 3 - x (K 0.5 Nd 0.5)TiO 3 (KNT100 x , x = 0.0, 0.02, 0.04, 0.06, 0.08 mol%) ceramics were fabricated and their microstructure and electrical properties were studied. All samples displayed a pseudo-cubic symmetry, and adding of KNT had little effect on grain size. The dielectric analysis displayed the dispersion increases with the addition of KNT compositions, showing strong relaxor properties. Besides, high dielectric constant (ε') of 23000 and dielectric peak temperature (T m) of 390 °C remain at 1 kHz in the x = 0.02 sample while the dielectric loss (tanδ) dropped below 0.5 in the range of 30–400 °C, showing excellent electrical insulation performance. In addition, doping of KNT had obvious influence on the strain, and a large strain (Smax) of 0.26% was obtained at x = 0.02 due to the increase of electrical insulation. More importantly, the strain at 50 kV cm−1 enhanced significantly with temperature increasing, reaching a maximum strain of 0.75% with a small hysteresis coefficient of 30% at 110 °C. Particularly, KNT02 exhibited excellent fatigue resistance within 105 fatigue cycles. Presumably these results are attributed to the coexistence of ferroelectric and non-ergodic relaxor domains and the thermally activated domain wall motion. [ABSTRACT FROM AUTHOR]