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The changes in the intensity of the southern tropical Indian Ocean dipole mode (STIOD) are investigated using observations and the Community Earth System Model Large Ensemble (CESM-LE) project in this study. The positive STIOD is characterized as cold SST anomalies over the tropical southeastern Indian Ocean (SEIO) and warm SST anomalies over the southcentral Indian Ocean (SCIO), which peak in boreal summer. It is suggested that the intensity of interannual variability in the STIOD experienced prominent interdecadal changes from 1970 to the present. The STIOD was relatively weak before the late 1980s, while it is enhanced significantly during the late 1980s to early-2000s and displayed some decrease in the intensity after the early-2000s. As an important generation mechanism, changes in the strengths of the Bjerknes feedback between the SCIO and SEIO mainly contribute to the variations of the STIOD intensity. The changes in Bjerknes feedback are associated with the variations in climatological mean states over the tropical Indian Ocean. The warmer climatological SST strengthens the efficiency of the SEIO SST in driving wind. On the other hand, the combined effects of the Indonesian Throughflow and surface climatological zonal winds alter the mean thermocline depth over the SEIO, contributing to the variations in the relationship between the thermocline depth and SST anomalies in situ. Two sets of historical and RCP8.5 simulations from CESM1-LE with 35 ensemble members are analyzed to confirm the roles of mean state changes on the intensity of interannual variability of STIOD. [ABSTRACT FROM AUTHOR]

It is well known that the Indian Ocean dipole (IOD) is closely related to El Niño-Southern Oscillation (ENSO). In this study, it is found that spring–summer north tropical Atlantic (NTA) sea surface temperature (SST) anomalies can contribute to the development of the IOD since the mid-1980s as well as ENSO. After the mid-1980s, an anticyclonic circulation over the subtropical northeastern Pacific could be excited by cool NTA SST anomalies in spring and summer due to a Gill-type Rossby-wave response. A low-level cyclonic circulation appears in the west Pacific in turn. The anomalous lower-level southwesterlies on the southeastern flank of the cyclonic circulation reduce the climatological wind speed, and thus, warm SST anomalies appear and extend to the central tropical Pacific via the wind-evaporation-SST (WES) feedback. As a result, Walker circulation over the Indo-Pacific region is changed, with anomalous descending in the eastern tropical Indian Ocean and ascending in the central tropical Pacific. The descending branch of anomalous Walker circulation generates surface southeasterly wind anomalies along the coast off Sumatra and lifts the thermocline in the eastern tropical Indian Ocean, which produces a positive IOD event in autumn. Such a cross-basin mechanism is supported by a coupled model experiment with warm SST perturbations over the NTA. In contrast, although cold NTA SST anomalies can induce warm SST anomalies in the eastern equatorial Pacific through interhemispheric meridional circulation before the mid-1980s, the responses in the tropical Indian Ocean are rather weak. In addition, the enhancement in the NTA-IOD relationship after the mid-1980s is suggested to result from the changes in the SST mean state under the context of global warming, which is confirmed by two coupled model experiments with different mean SST backgrounds. [ABSTRACT FROM AUTHOR]

• Three 1.6 m (Length) × 1.6 m (Width) diesel oil pool fire tests were carried out on two URTS in hot summer. • Shafts exhausted out of much smoke, but backflow occurred farther away from the fire sources. • Temperatures/velocities under the ceiling decayed longitudinally with the power index law. • The measured mass flow rates out of unit shafts were in range of 0.31 ∼ 1.76 kg/s.m2. • Dimensionless number Ri′ was adopted to assess the smoke flow under the shafts. Shallow-buried urban road tunnels with shafts (URTS) have been operated in large cities of China, and successfully released the traffic congestion. Fire smoke is expected to exhaust out of one-side shaft groups driven by its own thermal buoyancy. However, full-scale test data of the fire smoke spreading in such tunnel are still lacked, and the prediction models needs to be verified. In hot summer of year 2020, three full-scale experiments were carried out on two URTS. A 1.6 m (length) × 1.6 m (width) iron pan was placed on ground with diesel oil used as the fire source. Testing systems were arranged under the ceiling, on top openings of shafts and at bottoms of shafts. Lots of smoke were rapidly exhausted out of the shafts closer to the fire sources, but backflow occurred at bottoms of those shafts farther from the fire sources being not conducive to smoke extraction. Other three results of full-scale fire experiments conducted on one URTS in cold winter are provided here for comparison. The findings are that both the ceiling smoke temperatures and the smoke spreading velocities decayed longitudinally well with the exponential function, and the downstream temperature attenuation coefficient k 2 were in range of 0.042 ∼ 0.188 being smaller than that of the upstream, also the hotter the weather, the smaller the k 2 ; maximum values on top openings of the shafts were measured to be 47 °C in temperature, 5 m/s in velocity and 180 ppm in CO concentration; mass flow rates of the unit shafts were measured to decrease away from the fire sources that were 0.30 ∼ 1.77 kg/(s·m2) in Fires 1 and 2, and 0.46 ∼ 1.27 kg/(s·m2) in Fire 3, also the prediction models were confirmed not to be accurate enough; number R i ′ differed among all unit shafts of Shaft 6#, and were about 13.5 ∼ 15.2 in Fire 1, but smaller to be about 1.4 in Fire 2. [ABSTRACT FROM AUTHOR]

Slurry wall protection is the key to the success of the design and construction of underground diaphragm walls; however, in the analysis of its grooving mechanism, the original slurry in the surrounding environment was usually equivalated to the slurry pressure, while the slurry penetration characteristics and the formation of a filter cake were often neglected, leading to obvious defects in the existing literature. In this paper, by combining computational fluid dynamics (CFD) and the discrete element method (DEM), a model based on the strain softening constitutive equation was proposed to investigate the formation of a filter cake by the effects of slurry penetration and cementation and to calculate the stability of grooving. In this model, material parameters were used to describe the mechanical properties of the filter cake, and the microscopic parameters that were calibrated through experiments were used to explore the optimal particle radius ratio of the filter cake. Then, the feasibility and rationality of the model in describing the slurry penetration and failure trends were verified through comparative analysis. In the stability analysis, the safety factor was introduced to evaluate the impact of the slurry and other influencing factors on the grooving process. The results show that the properties of slurry and the environmental factors such as groundwater level have significant effects on the formation of the filter cake and stress distribution, thereby affecting the grooving effect. The findings of this study can provide useful guidance and reference for theoretical research and practical engineering. [ABSTRACT FROM AUTHOR]

The aim of this study is to explore the prognostic values and optimal cutoff point of time to positivity (TTP) of blood culture in children with Klebsiella pneumoniae (K. pneumoniae) bloodstream infection. Ninety-four children with K. pneumoniae bloodstream infection hospitalized in Children's Hospital of Chongqing Medical University from April 2014 to January 2019 were enrolled retrospectively. TTP and risk factors were determined and analyzed by receiver operating characteristic (ROC) analysis and logistic regression analysis. The standard cutoff point of TTP was 13 h. Patients in early TTP (≤ 13 h) group had significantly higher in-hospital mortality (37.93% vs 6.15%, P = 0.000), higher incidence of septic shock (44.83% vs 6.15%, P = 0.000), higher proportion of PRISM III scores ≥ 10 (48.28% vs 20.00%, P = 0.005), and higher proportion of hypoalbuminemia on admission (44.83% vs 18.46%, P = 0.008). Multivariate analysis indicated PRISM III scores ≥ 10, early TTP, and hypoalbuminemia on admission were independent risk factors of in-hospital mortality (OR 8.36, 95% CI 1.80–38.92, P = 0.007; OR 5.85, 95% CI 1.33–25.61, P = 0.019; OR 5.73, 95% CI 1.30–25.22, P = 0.021, respectively) and septic shock (OR 14.04, 95% CI 2.63–75.38, P = 0.002; OR 11.26, 95% CI 2.10–60.22, P = 0.005; OR 10.27, 95% CI 2.01–52.35, P = 0.005, respectively). Conclusion: Early TTP (TTP ≤ 13 h), PRISM III scores ≥ 10, and hypoalbuminemia on admission appeared to be associated with worse outcomes for K. pneumoniae bloodstream infection children. What is Known: • Klebsiella pneumoniae bloodstream infection is an important cause of infectious disease morbidity and mortality worldwide in children. • Short duration of time to positivity indicated poor clinical outcomes. What is New: • Time to positivity ≤ 13 h, along with PRISM III scores ≥ 10 and hypoalbuminemia on admission, indicated higher in-hospital mortality and incidence of septic shock in Klebsiella pneumoniae bloodstream infection children. • The cut-off point of TTP in this pediatric study was much longer than that reported in adult patients. [ABSTRACT FROM AUTHOR]

Abstract Ibuprofen (IBU), a nonsteroidal anti-inflammatory drug, is becoming an important member of pharmaceuticals and personal care products (PPCPs) as emerging pollutants. To degrade IBU, magnetic Fe 3 C nanoparticles embedded on N-doped carbon (Fe 3 C/NC) were prepared as a catalyst by a sol–gel combustion method. As characterized, the Fe 3 C/NC nanoparticles were composed of a NC nano-sheet and capsulated Fe 3 C particles on the sheet. The Fe 3 C/NC nanoparticles were confirmed an efficient catalyst for peroxymonosulfate (PMS) activation to generate sulfate radicals (SO 4 •-), single oxygen (1O 2) and hydroxyl radicals (•OH) toward the degradation of IBU. The added IBU (10 mg/L) was almost completely removed in 30 min by using 0.1 g/L Fe 3 C/NC and 2 g/L PMS. The catalyst was confirmed to have good ability and excellent reusability through leaching measurements and cycle experiments. A catalytic mechanism was proposed for the catalytic activation of PMS on Fe 3 C/NC, which involves both Fe 3 C reactive sites and N-doped carbon matrix as reactive sites in Fe 3 C/NC. Moreover, the degradation pathway of IBU in the Fe 3 C/NC-PMS system was proposed according to the detections of degradation intermediates. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

The analytical study of the reflection and transmission coefficient of the seafloor interface is essential for the characterization of the ocean bottom in marine seismic exploration. Based on the boundary conditions of the seafloor interface, the analytical expression of the reflection and transmission coefficient at the submarine interface is derived in this study by using the steady-state wave solution of the elastic wave in a homogeneous, isotropic medium. With this analytical expression, the characteristics of the reflection and transmission coefficient at the submarine interface are analysed and discussed using critical angles. The results show that the change in the reflection and transmission coefficient with the incidence angle presents a “segmented” characteristic, in which the critical angle is the dividing point. The amplitude value and phase angle of the coefficient at the submarine interface change dramatically at the critical angle, which is related to the P- and S-wave velocities in the seabed layer. Compared with the stiff seabed, the soft seabed has a larger P-wave critical angle and an absence of the converted S-wave critical angle, owing to the low P- and S-wave velocities in the solid seabed layer. By analysing and discussing the special changes that occur in the coefficient values at the critical angle, the reflection and transmission characteristics of the different incident angles are obtained. Synthetic models of both stiff and soft seafloors are provided in this study to verify the analytical results. Finally, we compared our synthetic results with real data from the Gulf of Mexico, which enabled the validation of our conclusions. [ABSTRACT FROM AUTHOR]

The unprecedented expansion and development of high-speed rail (HSR) in China provides a unique opportunity and a new way of thinking for addressing the problem of urban-rural wealth disparities. In this paper, I examine the impact of the introduction of HSRs on the income disparity between urban and rural residents in China. Using panel data from 285 prefecture-level cities from 2004 to 2018, in this paper I employ the double-difference method to assess the impact of HSR on the income gap between urban and rural populations and the mechanism of its action; furthermore, I explore the influence of HSR on urban residents' per capita disposable income and rural residents' per capita net income, as well as the impact of HSR on the flow of elements such as labor and capital. My research findings reveal that the introduction of HSR has greatly widened the income gap between urban and rural residents; however, there is heterogeneity between different East, Central, and West regions, as well as between different levels of cities. A further mechanism study finds that HSR lowers farmers' per capita net income, raises urban residents' per capita disposable income, and widens the urban/rural income gap via mechanisms such as facilitating the interregional mobility of labor and capital factors. Therefore, it is necessary to comprehensively assess the economic effects brought about by HSR, strengthen the construction of urban-rural transport networks, and improve support for rural areas, so as to promote the coordinated development of inter-regional and urban-rural areas. [ABSTRACT FROM AUTHOR]

Background/Aims: Renal involvement is one of the most common extra-articular complications caused by ankylosing spondylitis (AS). Most studies have focused on the incidence rate, clinical manifestation and pathology, while risk factors have hardly been investigated. Therefore, the objective of this study was to assess the risk factors of renal involvement in patients with AS. Methods: Clinical and biochemical data of 926 AS patients were collected. Based on the manifestations of renal involvement, patients were divided into three groups and the differences in clinical and biochemical characteristics were compared. A group with non-renal involvement served as a control. Multivariable logistic regression was used for analyzing risk factors of renal involvement in AS. Results: Of the 926 AS patients, 201 patients suffered from renal involvement. Moreover, female AS patients faced a higher risk of hematuria compared to male patients. As indicated by the data obtained from multivariate logistic regression analysis, gender, uric acid (UA), immunoglobulin A (IgA), and serum albumin (ALB) were found to be risk factors of renal involvement in AS. An increase in UA or IgA levels, or a decrease in ALB level can increase the risk of renal involvement with multiple manifestations (more than one manifestation of renal damage). According to our findings, no definite variable was identified as a risk factor of proteinuria in AS patients. Conclusion: In AS patients, UA, IgA, and ALB levels can indicate the risk of renal involvement in AS patient and need to be paid special attention. Furthermore, women are subjected to a higher risk of hematuria. [ABSTRACT FROM AUTHOR]

Metastable Bi 3+ self-doped NaBiO 3 (NBO) nanosheets were prepared by using acidic hydrolysis of NaBiO 3 ·2H 2 O in HNO 3 solutions. It was found that the as-prepared NBO nanosheets showed both chemical oxidation ability and photocatalytic oxidation activity for the degradation of carbamazepine under visible light irradiation. The pseudo-zero order reaction kinetic constant for the photodegradation of carbamazepine (20 mmol L −1 ) over the metastable NBO nanosheets was 0.087 min −1 , being 10.4 and 5.0 times that of the photocatalytic oxidation over the stable NBO nanosheets and the chemical oxidation over the metastable NBO nanosheets in dark, respectively. The enhanced photodegradation of carbamazepine over the metastable NBO nanosheets was mainly attributed to a reaction process of photocorrosion of the NBO nanosheets, which increased generation of singlet oxygen from the lattice oxygen of NBO and promoted a synergistic effect between the chemical oxidation and the photocatalytic oxidation. Singlet oxygen and photo-generated holes were identified as the major reactive species for photodegradation of carbamazepine. By a rough estimation, the (dark) chemical oxidation, photocorrosion process and photocatalysis contributed 19.4%, 60% and 20.6% of the total degradation of carbamazepine, respectively. Based on the identification of intermediates by GC– and LC–MS, two degradation pathways of carbamazepine in both chemical oxidation system and photocatalytic system were proposed. The developed dual-reactive-species-based photocatalysis may be a useful technology for the purification of water containing carbamazepine. [ABSTRACT FROM AUTHOR]

Background: Type I diabetes is a global public health concern that affects young people of reproductive age and can damage oocytes, reducing their maturation rate and blocking embryonic development. Understanding the effects of type I diabetes on oocytes is important to facilitate the maintenance of reproductive capacity in female diabetic patients. Methods: To analyze the effects of type I diabetes on mammalian oocytes, protein profile changes in mice with streptozotocin-induced type I diabetes were investigated using proteomic tools; nondiabetic mouse oocytes were used as controls. Immunofluorescence analysis for the spindle and mitochondria of oocytes. Results: We found that type I diabetes severely disturbed the metabolic processes of mouse oocytes. We also observed significant changes in levels of histone H1, H2A/B, and H3 variants in diabetic oocytes (fold change: > 0.4 or < -0.4), with the potential to block activation of the zygotic genome and affect early embryo development. Furthermore, diabetic oocytes exhibited higher abnormal spindle formation and spatial remodeling of mitochondria than observed in the controls. Conclusion: Our results indicate that type I diabetes disrupts metabolic processes, spindle formation, mitochondria distribution and modulates epigenetic code in oocytes. Such effects could have a major impact on the reproductive dynamics of female patients with type I diabetes. [ABSTRACT FROM AUTHOR]

A novel carbon nanohorns/poly(glycine) based sensor was successfully fabricated by electropolymerization of glycine at carbon nanohorns modified glassy carbon electrode for simultaneous determination of uric acid (UA), dopamine (DA) and ascorbic acid (AA). Electrochemical responses of as-prepared electrodes were investigated by cyclic voltammetry, electrochemical impedance spectroscopy and differential pulse voltammetry. Owing to the synergistic effect of carbon nanohorns and poly(glycine), three well defined and separated oxidation peaks were observed. Peak separations between AA and DA, DA and UA at as-prepared electrode were 130 and 120 mV, respectively. The current of the oxidation peaks showed a linear dependent on the concentrations of UA, DA and AA in the range of 2–350 μM, 1–280 μM and 30–450 μM, respectively, and the detection limits were calculated as 0.18, 0.03 and 0.34 μM (S/N = 3), respectively. Based on the simple preparation and prominent electrochemical properties, the obtained carbon nanohorns/poly(glycine) modified electrode was applied for the simultaneous determination of UA, DA and AA in the urine samples. [ABSTRACT FROM AUTHOR]

The severe soil erosion in the dry-hot valley (DHV) in southwestern China may result in heavy metal pollution in the Red River. However, little is known concerning the level of contamination, spatial distribution and environmental controls of the heavy metals in the soils of the DHV. Heavy metal concentrations in agricultural soils in a typical DHV catchment were investigated. Soil samples from both the topsoil (0–20 cm) and subsoil (20–40 cm) were collected at sixty-two sites, and the soil physical and chemical properties of sand, silt, clay, and organic matter contents; soil pH; bulk density; and the concentrations of Cr, Ni, Cu, Zn, and Pb were determined. Topographic factors of slope gradient, slope aspect, elevation, and topographic wetness index at each site were calculated using DEM. Kriging and canonical correspondence analyses were used to assess the spatial distribution of and environmental controls on heavy metals. The results demonstrated that the concentrations of Cr, Ni, Cu, Zn, and Pb in the DHV were higher than most of the reported values for agricultural soils worldwide and that the DHV may constitute a potential source of heavy metal pollution in the Red River. Considering each heavy metal individually, the vertical distribution in the topsoil and subsoil was similar at all of the sampling sites. High concentrations of Cr, Ni, Zn and Pb were observed at low elevations and low slope areas, and the spatial distribution pattern of Cu was contrary to that of Cr, Ni, Zn and Pb. The concentrations of heavy metals in the topsoil were controlled by both soil and topographical factors, while in the subsoil, they were primarily controlled by soil-related factors. It is concluded that high background concentrations, uncontrolled use of chemical fertilizers, and mining are the sources responsible for heavy metal contamination in the DHV region. [ABSTRACT FROM AUTHOR]

Many existing optimal solar-based hot water system design methods do not quantitatively consider the impact of energy mismatching, which leads to the overestimation of system performance and misleads the optimal design of the system. For addressing such mismatching problems, a solar-based hot water system optimization design method based on real-time energy balancing and co-adaptive matchmaking is proposed. It consists of three main parts: (1) establish a simplified solar hot water system model based on the real-time energy balance to simulate the dynamic energy performance of the system; (2) propose a co-adaptive matchmaking optimization method to minimize the energy mismatch between the supply and demand sides of the system; and (3) identify the scheme with the minimum life-cycle total cost as the optimum design. A multiple-function solar water heating system for the domestic hot water supply, space heating and air conditioning of a kindergarten building in Beijing was optimized based on the proposed optimization method. It was found that the energy mismatch degree between the supply and demand sides can be greatly reduced and leading to a maximum life-cycle saving cost up to 20.13% in the concerned case. [ABSTRACT FROM AUTHOR]

• The Indian continental lithosphere is explored to a depth of 100 km beneath Myanmar. • The underlying Indian lower crust may have experienced partial eclogitization. • A low velocity anomaly beneath the Monywa volcano indicates its latest volcanism. The Indian plate descends obliquely eastward beneath the Eurasian plate along the Burmese arc. Previous tomographic results revealed a high-velocity structure that plunges eastward into the deep mantle beneath Myanmar. However, the shallow structure beneath Myanmar remains unclear due to the lack of local seismic observations. Based on the local seismic data recorded by a newly deployed dense array in Myanmar, we obtain a three-dimensional velocity structure of the crust and lithospheric mantle above 100 km by employing the double-difference tomography method. Our imaging results support the existence of the Indian continental lithosphere to a depth of at least 100 km with a dip angle of ∼25° beneath the Indo-Burma Ranges and the Central Myanmar Basin. At the deep end of the continental slab, the high V P , high Vs and rather low average V P / V S ratio indicate that the lowermost portion of the crust from 80 to 120 km may have experienced partially metamorphic eclogitization. The imaging results also provide direct seismic evidence for the origin of the last Monywa volcanic activity in the Holocene. This subduction-related volcanism is characterized by a prominent low Vs anomaly in the lithospheric mantle, which indicates continental lithosphere dehydration and partial melting in mantle wedge. These findings provide new seismic constraints to understand the continental collision system between India and Eurasia under Myanmar and the related magmatic activities of the Monywa volcano. [ABSTRACT FROM AUTHOR]

Early appropriate antimicrobial therapy plays a critical role for patients with Staphylococcus aureus bloodstream infection (SAB). We aim to determine the optimal time-window for appropriate antimicrobial therapy and evaluate the effects of delayed therapy on adverse clinical outcomes (in-hospital mortality, sepsis, and septic shock) in children with SAB by propensity score matching (PSM) analysis. Receiver-operating characteristic was used to determine the cut-off point of the time to appropriate therapy (TTAT), the patients were divided into timely and delayed appropriate antimicrobial therapy (delayed therapy) groups accordingly. The PSM was used to balance the characteristics between the two groups, controlling the effects of potential confounders. Kaplan-Meier methods and Cox proportional hazards regression were applied to the matched groups to analyze the association between delayed therapy and clinical outcomes. Inverse probability of treatment weighting and propensity score covariate adjustment were also performed to investigate the sensitivity of the results under different propensity score-based approaches. In total, 247 patients were included in this study. The optimal cut-off point of TTAT was identified as 6.4 h, with 85.0% sensitivity and 69.2% specificity (AUC 0.803, 95% confidence interval 0.702–0.904). Eighty-seven (35.22%) of the 247 patients who received delayed therapy (TTAT ≥ 6.4 h) had higher in-hospital mortality (19.54% vs 1.88%, p < 0.001), higher incidences of sepsis (44.83% vs 15.00%, p < 0.001) and septic shock (32.18% vs 6.25%, p < 0.001) when compared to timely therapy (TTAT < 6.4 h) patients. After PSM analysis, a total of 134 episodes (67 in each of the two matched groups) were further analyzed. No statistically significant difference was observed in in-hospital mortality between delayed and timely -therapy groups (log-rank test, P = 0.157). Patients with delayed therapy had a higher incidence of sepsis or septic shock than those with timely therapy (log-rank test, P = 0.009; P = 0.018, respectively). Compared to the timely-therapy group, the hazard ratio and 95% confidence interval in delayed-therapy group were 2.512 (1.227–5.144, P = 0.012) for sepsis, 3.109 (1.166–8.290, P = 0.023) for septic shock.    Conclusion: Appropriate therapy delayed 6.4 h may increase the incidence of sepsis and septic shock, with similar in-hospital mortality in patients with SAB.What is Known:• Staphylococcus aureus (S. aureus) is a major cause of bloodstream infections in children. Undoubtedly, early antimicrobial application plays a critical role in the treatment of children with Staphylococcus aureus bloodstream infections (SAB).• However, rapid, and aggressive administration of antimicrobials may lead to the overuse of these drugs and the emergence of multidrug-resistant microorganisms. Therefore, it is crucial to determine the optimal time-window for appropriate antimicrobial administration in children with SAB. Unfortunately, the optimal time-window for appropriate antimicrobial administration in children with SAB remains unclear.What is New:• Determining the optimal time-window for appropriate antimicrobial administration in patients with matched data variables is particularly important. The Propensity score matching (PSM) analysis effectively controls for confounding factors to a considerable extent when assessing the impact of treatment, thereby approximating the effects observed in randomized controlled trials.• To our knowledge, this is the first study using PSM method to assess the effects of delayed appropriate antimicrobial therapy on adverse outcomes in children with SAB. In low-risk populations with SAB, a delay of 6.4 h in appropriate therapy might increase the occurrence rate for sepsis and septic shock; however, no correlation has been found between this delay and an increased risk for hospital mortality.What is Known:• Staphylococcus aureus (S. aureus) is a major cause of bloodstream infections in children. Undoubtedly, early antimicrobial application plays a critical role in the treatment of children with Staphylococcus aureus bloodstream infections (SAB).• However, rapid, and aggressive administration of antimicrobials may lead to the overuse of these drugs and the emergence of multidrug-resistant microorganisms. Therefore, it is crucial to determine the optimal time-window for appropriate antimicrobial administration in children with SAB. Unfortunately, the optimal time-window for appropriate antimicrobial administration in children with SAB remains unclear.What is New:• Determining the optimal time-window for appropriate antimicrobial administration in patients with matched data variables is particularly important. The Propensity score matching (PSM) analysis effectively controls for confounding factors to a considerable extent when assessing the impact of treatment, thereby approximating the effects observed in randomized controlled trials.• To our knowledge, this is the first study using PSM method to assess the effects of delayed appropriate antimicrobial therapy on adverse outcomes in children with SAB. In low-risk populations with SAB, a delay of 6.4 h in appropriate therapy might increase the occurrence rate for sepsis and septic shock; however, no correlation has been found between this delay and an increased risk for hospital mortality. [ABSTRACT FROM AUTHOR]

The authors regrets that there is a typo error on the Abbreviation section of their published paper. "Area under the curve" should have been abbreviated to "AUC" instead of "A". The authors have requested that this be noted. The original article has been corrected. [ABSTRACT FROM AUTHOR]

Release behaviors of drugs from drug deliveries are crucial for the enhancement of therapy efficiency, reduction of toxicity and patient compliance. Herein, antisolvent crystallization is employed to coat methlyene blue (MB)-loaded silica by shellac precipitation (silica-MB@shellac), which is simultaneously induced by outward diffusion of H+ ions from particular silica-MB. The encapsulation of shellac shell on silica-MB modulates the aggregation state of MB, which endows silica-MB@shellac a decreased MB's thermal stability, enhanced photoluminescence intensity, improved stability against in vitro reduction by ascorbic acid and retained photodynamic therapy activity. From the absorbance of MB supernatant obtained during incubation, the concentrations of MB monomers and dimers are determined via a non-linear regression analysis to investigate the influence of shellac coating on MB's release mechanisms from silica-MB@shellac. According to the simulated models, small diffusion constants of MB are caused by limited diffusion through shellac shells with high compaction degrees. These are observed for samples synthesized under high supersaturation degree during antisolvent crystallization. High degree of supersaturation is achieved through increasing shellac concentration, additive amount and dropping rate of antisolvent, as well as decreasing pH values of aqueous buffers as antisolvent. Furthermore, a combined mechanism of Fickian diffusion and Case-IΙ relaxation is proposed to describe the release behaviors of MB monomer and dimers from silica-MB@shellac. Therefore, this work may shed light on the encapsulation method of polymer on drug-loaded powders and the control of aggregation states of photosensitizers to promote the photoluminescence intensity, photodynamic therapy efficiency and controlled release behaviors. Image 1 • Antisolvent crystallization is employed to coat silica-MB by shellac precipitation. • The encapsulation of shellac on silica-MB modulates the aggregation state of MB. • MB diffuses slowly from silica-MB@shellac synthesized with high supersaturation degree. • Fickian diffusion and Case-IΙ relaxation mechanisms describe the release behaviors. [ABSTRACT FROM AUTHOR]

• Neonatal S. pneumoniae pneumonia induced airway HMGB1 production. • HMGB1 activates TLR4 to promote airway smooth muscle myosin heavy chain (SMMHC) expression and AHR in neonatal S. pneumoniae pneumonia mice. • HMGB1/TLR4 promotes SMMHC expression and AHR by inhibiting ERK phosphorylation in neonatal S. pneumoniae pneumonia model. Our previous study showed that neonatal S. pneumoniae pneumonia promoted airway smooth muscle myosin heavy chain (SMMHC) expression and AHR development. Researches demonstrated HMGB1, TLR4 and ERK are involved in smooth muscle contractile protein expression, so we hypothesis that HMGB1/TLR4/ERK pathway participated in airway SMMHC overexpression in neonatal S. pneumoniae pneumonia model. Neonatal (1-week-old) BALB/c mice were intranasal inoculated with D39 to establish non-lethal S. pneumoniae pneumonia model. TLR4 was inhibited 2 weeks after infection with TLR4 specific inhibitor (TAK-242). Five weeks after infection, the bronchoalveolar lavage fluid (BALF) and lungs of neonatal S. pneumoniae pneumonia and mock infection mice with or without TLR4 inhibition were collected to assess the expressions of HMGB1, TLR4 and p-ERK1/2. Airway Hyperresponsiveness (AHR) of the three groups was determined by whole-body plethysmograph. Our results demonstrated that neonatal S. pneumoniae pneumonia promoted HMGB1/TLR4 production, SMMHC expression and AHR development significantly, with ERK1/2 phosphorylation decreased remarkably. TLR4 inhibition after pneumonia significantly increased ERK1/2 phosphorylation, reversed airway SMMHC overexpression and alleviated AHR. Neonatal S. pneumoniae pneumonia promotes airway SMMHC expression and AHR through HMGB1/TLR4/ERK. [ABSTRACT FROM AUTHOR]

The Indian Ocean Dipole (IOD) with worldwide socio-economic impacts has been presented to mature either in boreal summer or autumn, leading to the classification of summer IOD and autumn IOD. Investigating the climate dynamics to distinguish between these two types of IOD can improve our understanding and prediction of the surrounding weather and climate. This study demonstrates that the emergence of the summer IOD is mainly attributed to internal air-sea interactions in the western tropical Indian Ocean (WIO), while the autumn IOD is significantly related to ENSO development. For the summer IOD, broad-scaled warm sea surface temperature anomalies in the WIO are conducive to the enhancement of convective perturbations. Then local ocean–atmosphere feedback associated with changes in convection and surface heat flux into the upper ocean plays a key role in triggering the summer IOD. For the autumn IOD, strong easterly wind anomalies in the eastern Indian Ocean initiate oceanic Rossby waves and Bjerknes feedback, leading to the formation of both the western and eastern poles. It is recognized that these intensified easterly wind anomalies mostly benefit from ENSO variability. The distinctive features and air-sea interactions intrinsic to the summer IOD and the autumn IOD revealed in this study can further contribute to more credible predictive models of diverse IOD events. [ABSTRACT FROM AUTHOR]

Background: Staphylococcus aureus (S. aureus) is a common cause of bacteremia, which leads to significant morbidity and mortality. We investigated the relationship between time to positivity (TTP) and clinical outcomes in children with S.aureus bacteremia in the China.Methods: A retrospective study of Staphylococcus aureus bacteremia inpatient was performed in Children's Hospital of Chongqing Medical University in China between 29 January 2014 and 29 August 2017. TTP and clinical parameters were determined and analyzed. The receiver operating characteristic (ROC) curves were plotted for optimal cut-off selection, multivariate logistic regression tests were performed to evaluate the association between TTP and clinical outcomes.Results: Overall, 84 cases were enrolled. We stated that in-hospital mortality is significantly higher in the early TTP (≤17 h) than in the late TTP (> 17 h) group (57.14% vs 7.14%, P = 0.000). Septic shock occurred in 57.14% of patients with early TTP and in 18.57% of patients with late TTP (P = 0.002). Detailed multivariate and statistical analysis revealed that early TTP, need for vasoactive agent were independent risk factors of in-hospital mortality; early TTP, need for vasoactive agent and APACHE II score ≥ 15 were independent risk factors of septic shock incidence in S. aureus bacteremia children.Conclusions: Overall, TTP of ≤17 h appeared to correlate with the worse outcomes for S. aureus bacteremia children. These results have important implications in the assessments and management of pediatric S. aureus bacteremia in a clinical setting.Trial Registration: Retrospectively registered. [ABSTRACT FROM AUTHOR]

Highlights • EG erosion showed an order of after harvested > before planted > after planted. • EG erosion under different tillage practices were CK＞CT ＞CRT-25＞CRT-40V＞CRT-40S. • Conventional tillage farmlands had to be abandoned since the endless developing of EG. • Tillage practice was the dominant control on EG erosion in the dry-hot valley. Abstract Ephemeral gully (EG) erosion can cause soil loss and result in soil degradation. Appropriate tillage practices are beneficial to soil conservation and avail against soil erosion. Currently, how tillage contributes to soil erosion of EG at the catchment scale is still unclear. To quantify EG erosion and analyze the effects of tillage practice on EG erosion in a typical farmed dry-hot valley catchment, EGs under five tillage practices including conventional tillage (CT), contour ridge tillage in sugarcane land (CRT-40S), vegetable land (CRT-40 V) and in orange land (CRT-25), and without tillage in abandoned land (CK) were investigated. Five field surveys were conducted during two growing seasons from April 2013 to February 2015. The results showed that EG erosion was most serious after crops being harvested, followed by that before crops being planted, after crops being planted subsequently. The average EG erosion modulus of two growing seasons was 231.85 t km−2 a−1. Considering the effect of tillage practices, EG erosion modulus was the largest under CK, followed by CT, CRT-25, CRT-40 V and CRT-40S subsequently, indicating that contour ridge tillage practice would benefit for controlling EG erosion. We found that farmlands with conventional tillage practice had to be abandoned when EGs were developed intensively. But EG erosion did not terminate after being abandoned. The redundancy analysis further confirmed that tillage practice was the dominant control on EG erosion in the dry-hot valley. Our results suggested that appropriate tillage practice such as contour ridge tillage can efficiently restrain EG erosion in the dry-hot valley. [ABSTRACT FROM AUTHOR]

Abstract The patterns of primary flow jet core in steam ejector were investigated using computational fluid dynamics (CFD) method. Simulations based on ideal gas model at different operating conditions were performed. The results demonstrate the pattern of primary pseudo-shock flow was affected by the operating conditions obviously when value of operating condition was bigger than that of the critical condition. Compared with the results generated from ideal gas modelling, the primary pseudo-shock flow predicted by wet steam model has a similar pattern and almost the same effective area. But the wet steam model based simulation gives a further downstream choking position and a higher secondary fluid flow velocity at choking position. The above two factors lead to improved entrainment ratio (E m) and increased critical back pressure of steam ejector compared to the results generated from ideal gas modelling. More importantly, the wet steam model predictions show better agreement with the experimental data. Highlights • Study the pumping mechanism of ejector by primary pseudo-shock flow pattern. • The primary pseudo-shock flow pattern affected by the operating conditions. • Secondary fluid flow divided into three modes based on flow pattern analysis. • Operating condition less than critical parameter sustains a stable entrainment process. • Wet steam model captures primary pseudo-shock flow pattern more accurately. [ABSTRACT FROM AUTHOR]

• Application of basalt fiber in hydraulic asphalt concrete. • Effect of temperature on fracture performance of hydraulic asphalt concrete. • Discrete element method is used to reveal the action mechanism of fiber. • The failure mechanism of hydraulic asphalt concrete is analyzed from the micro level. An asphalt concrete anti-seepage core wall may be faced with the risk of cracking due to problems like uneven settlement of the foundation during the service period. Considering that hydraulic asphalt concrete (HAC) has a high asphalt content while basalt fibers have excellent tensile properties and good compatibility with asphalt, adding basalt fibers into HAC may potentially form a useful material for hydraulic engineering. Therefore, it is of great significance to comprehensively examine the fracture properties of this new composite material from both macroscopic and mesoscopic perspectives. To explore the effect of basalt fibers on the fracture performance of HAC, an experimental study was carried out on hydraulic basalt fiber asphalt concrete (HBFAC) under different temperatures by considering 3 fiber lengths and 4 fiber contents. The results showed that, when the temperature remained constant, the fracture load, fracture toughness and fracture energy of HAC all exhibited an upward trend with the increase of fiber content, and reached the maximum values at the fiber content of 4‰. Of different fiber lengths, the maximum fracture load, fracture toughness and fracture energy were observed at the fiber length of 6 mm. With the growth of temperature, the fracture load and fracture toughness exhibited a decreasing trend, while the fracture energy showed an increasing trend. At the same time, the increase in fracture load and fracture toughness due to the fiber reinforcing effect was gradually enlarged, but the increase in fracture energy was gradually reduced. Overall, the optimum fiber length and fiber content were determined to be 6 mm and 4‰, respectively. Subsequently, the fiber properties were further investigated with the discrete element method, and the results of internal mesoscopic mechanical behavior, crack development and particle displacement indicate that basalt fibers play a positive role in dispersing stress and inhibiting crack development so as to improve the toughness and cracking resistance of HAC. Finally, the failure mechanism of HBFAC at different temperatures was revealed from a mesoscopic level. The outcome of this paper provides a theoretical basis for the research and application of basalt fibers in HAC. [ABSTRACT FROM AUTHOR]

Background: Currently, there are no reliable clinical tools available to identify persistent asthma symptoms among preschool children with recurrent wheezing. We investigated iron homeostasis in the airways of preschoolers with recurrent wheezing and assessed whether iron homeostasis-related indices may reliably predict persistent wheezing. Methods: Iron levels and mRNA expression levels of iron homeostasis molecules were examined in bronchoalveolar lavage samples from 89 preschoolers with recurrent wheezing and 56 controls, with a 12-month follow-up conducted. Risk factors for persistent wheezing were identified using least absolute shrinkage and selection operator and multivariate logistic regression. The addition of predictive values of iron indices to the modified Asthma Predictive Index (mAPI) or clinical predictors was determined using area under receiver operating characteristic curves (AUC). Results: Preschoolers with recurrent wheezing had reduced iron levels in their airways, associated with significantly decreased expression of iron export molecule SLC40A1 and increased expression of iron intake factor TFR1 and iron storage factors FTH and FTL. Risk factors for persistent wheezing included mAPI positivity, iron predictors (lower expression of SLC40A1 and higher expression of FTL), and clinical predictors (aeroallergen sensitivity, shorter breastfeeding duration, and earlier age of first wheezing episode). The addition of information on iron predictors significantly enhanced the power of clinical predictors (AUC: 84%, increase of 12%) and mAPI (AUC: 81%, increase of 14%). Conclusions: Iron homeostasis is altered in the airways of preschoolers with recurrent wheezing. Adding information on iron-related indices to clinical information significantly improves accurate prediction of persistent wheezing in preschool-aged children. [ABSTRACT FROM AUTHOR]

Persistent S. aureus bloodstream infection (PSBSI) increased the incidence of metastatic infection and mortality. We aimed to clarify its risk factors and correlation with metastatic infection and septic shock in children. This retrospective and observational study enrolled children with S. aureus bloodstream infection who admitted to Children's Hospital of Chongqing Medical University between January 2016 and December 2021. The logistic regression model was used for multivariable analyses to determine independent factors associated with PSBSI and clarify the effect of persistent S. aureus bloodstream infection and other factors on metastatic infection and septic shock. One hundred and twenty-seven children were included in this study retrospectively. There were thirty-two cases in the persistent S. aureus bloodstream infection group and ninety-five children in the non-persistent infection group. Multivariate logistic regression analysis indicated that inappropriate empirical antibiotic therapy (OR, 7.26; 95%CI, 2.48–21.30; P<0.01) was an independent risk factor of persistent S. aureus bloodstream infection. Persistent S. aureus bloodstream infection (OR, 6.40; 95%CI, 2.08–19.70; P<0.01) and community-acquired S. aureus bloodstream infection (OR, 4.75; 95%CI, 1.34–16.89; P=0.02) were independent predictors of metastatic infection. Pittsburgh bacteremia scores ≥ 2 (OR, 28.81; 95%CI, 5.26–157.99; P<0.01), hypoalbuminemia (OR, 13.34; 95%CI, 2.43–73.28; P<0.01) and persistent S. aureus bloodstream infection (OR, 5.48; 95%CI, 1.13–26.54; P=0.04) were independent risk factors of septic shock. Conclusion: Inappropriate empirical antibiotic therapy was an independent risk factor of pediatric persistent S. aureus bloodstream infection. Pediatric persistent S. aureus bloodstream infection was associated with metastatic infection and septic shock. What is Known: • Pathogenic features such as Methicillin-resistant S. aureus and sources of infection such as central venous catheter related infection were risk factors of PSBSI in adults. • PSBSI increased the incidence of metastatic infection and mortality in adults. What is New: • Inappropriate empirical antibiotic therapy was an independent risk factor of pediatric persistent S. aureus bloodstream infection. • Pediatric persistent S. aureus bloodstream infection was associated with metastatic infection and septic shock. [ABSTRACT FROM AUTHOR]

In order to examine the compression-shear combined mechanical properties of rubber fiber concrete, an experimental study was carried out on rubber fiber concrete of three different configurations using a material compression-shear testing machine by considering different axial compression ratios. The failure modes and shear stress-strain curves of rubber fiber concrete under different loading conditions were obtained. By comparatively analyzing the mechanical parameters of rubber fiber concrete under different axial compression ratios, the following conclusions were drawn. With the increase of the axial compression ratio, the failure mode in the shear direction gradually developed from a relatively straight crack to a main crack accompanied by a certain amount of axial cracks; meanwhile, the number of concrete slags on the shear failure section was gradually increased and the friction marks were gradually deepened. The addition of rubber particles increased the randomness and discreteness of the concrete upon failure, while fibers inhibited the development of oblique micro-cracks and the dropping of concrete slags. The shear stress of the concrete specimen containing rubber particles was significantly lower than those without rubber particles. Comparatively, fibers showed little effect on the shear stress. As the axial compression ratio increased, the shear stress and shear strain of rubber fiber concrete were gradually increased, but the increasing amplitude of shear stress tended to become flattened. Under the influence of the axial compression ratio, the shear stress of C-0%-0%, C-30%-0%, and C-30%-0.6% was increased by 4.57 times, 3.26 times, and 2.69 times, respectively, suggesting a gradually decreasing trend. At the same time, based on the principal stress space and the octahedral stress space, the compression-shear combined failure criterion was proposed for the three different rubber fiber concretes. The research findings are of great significance to the engineering application and development of rubber fiber concrete. [ABSTRACT FROM AUTHOR]

Magnesium aluminate (MgAl 2 O 4) spinel ceramics have gained widely using in some crucial industries by right of superior properties. However, their further applications have been restricted by the complicated preparing technology and high processing cost. In the present work, a series of MgAl 2 O 4 spinel ceramics with high-density have been fabricated by solid-state reaction sintering. Role of different composite oxide additives including Sm 2 O 3 –Y 2 O 3 , Sm 2 O 3 –Nb 2 O 5 , and Sm 2 O 3 –La 2 O 3 respectively, on phase compositions, morphologies, sintering characteristics, mechanical properties, and thermal stability of as-prepared MgAl 2 O 4 spinel ceramics was investigated. Some secondary phases such as Y 3 Al 5 O 12 , SmAlO 3 , and MgAl 11 LaO 19 were formed. Due to the synergistic effect of the secondary phases and consequent solid solutions, the densification and properties of MgAl 2 O 4 spinel ceramics were obviously promoted. Simultaneously, the positive effects were also intuitively manifested in the decrease of apparent porosity and increase of the cold compressive strength and thermal shock resistance. • A potential candidate for preparing MgAl 2 O 4 spinel ceramics was proposed. • The synergistic effects of Sm 2 O 3 -(Y 2 O 3 , Nb 2 O 5 and La 2 O 3) respectively were investigated. • The phase and microstructure evolution mechanisms were presented graphically. [ABSTRACT FROM AUTHOR]

Background: Pseudomonas aeruginosa (P. aeruginosa) is a major Gram-negative pathogen, which has been reported to result in high mortality. We aim to investigate the prognostic value and optimum cut-off point of time-to-positivity (TTP) of blood culture in children with P. aeruginosa bacteremia.Methods: From August 2014 to November 2018, we enrolled the inpatients with P. aeruginosa bacteremia in a 1500-bed tertiary teaching hospital in Chongqing, China retrospectively. Receiver operating characteristic (ROC) analysis was used to determine the optimum cut-off point of TTP, and logistic regression were employed to explore the risk factors for in-hospital mortality and septic shock.Results: Totally, 52 children with P. aeruginosa bacteremia were enrolled. The standard cut-off point of TTP was18 h. Early TTP (≤18 h) group patients had remarkably higher in-hospital mortality (42.9% vs 9.7%, P = 0.014), higher incidence of septic shock (52.4% vs12.9%, P = 0.06), higher Pitt bacteremia scores [3.00 (1.00-5.00) vs 1.00 (1.00-4.00), P = 0.046] and more intensive care unit admission (61.9% vs 22.6%, P = 0.008) when compared with late TTP (> 18 h) groups. Multivariate analysis indicated TTP ≤18 h, Pitt bacteremia scores ≥4 were the independent risk factors for in-hospital mortality (OR 5.88, 95%CI 1.21-21.96, P = 0.035; OR 4.95, 95%CI 1.26-27.50, P = 0.024; respectively). The independent risk factors for septic shock were as follows: TTP ≤18 h, Pitt bacteremia scores ≥4 and hypoalbuminemia (OR 6.30, 95%CI 1.18-33.77, P = 0.032; OR 8.15, 95%CI 1.15-42.43, P = 0.014; OR 6.46, 95% CI 1.19-33.19 P = 0.031; respectively).Conclusions: Early TTP (≤18 hours) appeared to be associated with worse outcomes for P. aeruginosa bacteremia children. [ABSTRACT FROM AUTHOR]

. [ABSTRACT FROM AUTHOR]

Background: Staphylococcus aureus (S. aureus) bacteremia (SAB) has high morbidity and mortality, with the development of methicillin-resistant S. aureus (MRSA) and the recognized shortcomings of vancomycin, its management is becoming more complicated. Considering the capability to penetrate cells, tissues and biofilms, rifampin has been used as adjunctive agent to against staphylococcal activity. Objectives: We performed this meta-analysis, aimed to explore the efficacy of adjunctive rifampin for the treatment of SAB. Methods: Medical literatures were searched in the Pubmed, Medline, Embase and Cochrane databases up to October 2018. Patients with SAB received treatment with or without rifampin were included. The risk ratio (RR) and 95% confidence intervals (CI) of mortality, rate of bacteriological failure and relapse were estimated. Results: Seven articles (five randomized controlled trials and two retrospective cohort studies) enrolling 979 and 636 patients of SAB treated with and without rifampin, respectively, were included. There was no difference of mortality between the adjunctive rifampin therapy and standard therapy on SAB (RR: 0.771, 95% CI: 0.442 to 1.347, I2 = 70.4%). In the subgroup analyses, the decreased mortality was observed in the adjunctive rifampin treatment for patients without MRSA infection (RR: 0.509, 95% CI: 0.372 to 0.697, I2 = 8.8%). In addition, there was no difference of the rate of bacteriologic failure (RR: 0.602, 95% CI: 0.198 to 1.825, I2 = 0.0%) or relapse (RR: 0.574, 95% CI: 0.106 to 3.112, I2 = 77.9%) between the adjunctive rifampin therapy and standard therapy on SAB. Conclusions: In general, insufficient evidence supported the efficacy of adjunctive use of rifampin for treatment of SAB, adding rifampin to standard therapy didn't decrease the incidence of death, rate of bacteriologic failure and relapse. [ABSTRACT FROM AUTHOR]

We aimed to investigate the relationship between time to positivity (TTP) of blood cultures and clinical outcomes in children with S. pneumoniae bacteremia. Children with S. pneumoniae bacteremia hospitalized in Children's Hospital of Chongqing Medical University from May 2011 to December 2017 were enrolled retrospectively. Overall, 136 children with S. pneumoniae bacteremia were enrolled. The standard cutoff TTP was 12 h. We stated that in-hospital mortality is significantly higher in the early TTP (≤ 12 h) group than that in the late TTP (> 12 h) group (41.70% vs 8.00%, P < 0.001). Septic shock occurred in 58.30% of patients with early TTP and in 21.00% of patients with late TTP (P < 0.001). Independent risk factors of in-hospital mortality and septic shock in children with S. pneumoniae bacteremia included early TTP, need for invasive mechanical ventilation, and PRISM III score ≥ 10. Overall, TTP ≤ 12 h appeared to associate with the worse outcomes for children with S. pneumoniae bacteremia. [ABSTRACT FROM AUTHOR]

Abstract In this study, the cause of the boundary layer separation, the determination of the separated region and the effect of the boundary layer separation on ejector performance were comprehensively investigated. The boundary layer separation inside the ejector was studied by using CFD method. A steam ejector refrigeration experimental system was set up to verify the numerical model. The degree of boundary layer separation was determined by back pressure and the ejector geometry parameters. The cause of ejector failure was analyzed. The influence of the boundary layer separation on ejector performance under different throat diameters and the nozzle exit positions (NXP) were investigated in detail. The results indicated that in certain size range of the throat diameter or the NXP, the ejector worked in critical mode and has better pumping performance when the operating conditions were constant. In the case of a small or large throat diameter or a large NXP, the boundary layer separation became more severe, the formation of the shock wave and the choke would be destroyed and the mixed fluid would not overcome the back pressure to discharge from the ejector. The efficiency of the ejector descended to zero, the ejector failed. Highlights • A steam ejector refrigeration system was set up to verify the CFD model. • The GCI method was presented for analyzing the grid density. • Formation and delimitation of the boundary layer separation was investigated. • The boundary layer separation influence on the ejector performance was studied. • Effects of throat diameter and the NXP on the boundary layer separation were analyzed. [ABSTRACT FROM AUTHOR]

Our previous study showed that neonatal S. pneumoniae infection aggravated airway inflammation and airway hyperresponsiveness (AHR) in an OVA-induced allergic asthma model. As airway smooth muscle (ASM) plays a pivotal role in AHR development, we aim to investigate the effects of neonatal S. pneumoniae pneumonia on ASM structure and AHR development. Non-lethal neonatal pneumonia was established by intranasally infecting 1-week-old BALB/C mice with the S. pneumoniae strain D39. Five weeks after infection, the lungs were collected to assess the levels of α-SMA and the contractile proteins of ASM. Our results indicate that neonatal S. pneumoniae pneumonia significantly increased adulthood lung α-SMA and SMMHC proteins production and aggravated airway inflammatory cells infiltration and cytokines release. In addition, the neonatal S. pneumoniae pneumonia group had significantly higher Penh values compared to the uninfected controls. These data suggest that neonatal S. pneumoniae pneumonia promoted an aberrant ASM phenotype and AHR development in mice model. [ABSTRACT FROM AUTHOR]

A composite of Fe/Fe 3 C and N-doped graphitic carbon (Fe/Fe 3 C@NG) was prepared and used as a catalyst for the activation of peroxymonosulfate (PMS) toward the oxidative degradation of Norfloxacin (NOF). It was observed that Fe/Fe 3 C@NG behaved as a bifunctional material, showing both good adsorption ability and catalytic activity. The maximum adsorption capacity of Fe/Fe 3 C@NG for NOF was evaluated as 0.13 mmol g −1 . Under given conditions (NOF concentration 0.1 mmol L −1 , catalyst load 0.1 g L −1 and PMS addition 1 mmol L −1 ), the degradation of NOF was almost completely achieved in 20 min with a degradation rate constant of 0.22 min −1 . A non-radical mechanism was proposed for the activation of PMS by Fe/Fe 3 C@NG by the scavenging test, EPR and chronoamperometry analysis. The fast and complete degradation of NOF was achieved via a rapid electron transform, in which both PMS and NOF molecular were adsorbed on the surface of Fe/Fe 3 C@NG and PMS was activated by obtaining electrons from NOF to oxidize NOF. The present study provides a green bifunctional catalyst for the oxidative removal of organic pollutants in various environmental media. [ABSTRACT FROM AUTHOR]

Recently, chitosan is discovered as a most abundant natural polymer, which is not only a lightweight, low‐cost, sustainable resource with potentials in energy transformation, but also biocompatibility and biodegradability. In this article, they investigated a highly biocompatible chitosan‐based electro‐active polymer (C‐Polymer) actuator composed of multiwall carbon nanotube, ionic liquid, and polymer‐supported chitosan. As a result, after the changed MCNTs rate (20%, 40%, 60%, and 80%) in the electrode membrane, actuation properties of C‐polymer actuator behaved a great enhancement. With the increase of the ratio of MCNTs, the specific capacitance and the electrode resistance were obviously improved, which were 2.02 F/g and 1.32 Ω under rate of 80%, and the maximum displacement and the response speed behaved a peak value of 7 mm (80%) and 0.032 mm/s (80%). Interestingly, it also showed an increasing for the maximum blocking force and response speed under the ratio of 80%, which presented the maximum value of 6.80 mN and 0.11 mN/s. In order to analyze causes for this enhancement, a valid generated strain values were calculated to evaluate the strain on the electrode layer. However, it is exhibited that the generated strain was very small, which almost kept in the value of 0.5%, and it was unrelated to Young's modulus. Moreover, they also found that the resistance and the specific capacitance could strongly affect the electromechanical properties of C‐polymer actuator with different rate of MCNTs, and revealed a vital potential Ramsay rule between the electrochemical properties and electromechanical properties of C‐polymer actuator. POLYM. COMPOS., 39:E228–E235, 2018. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Background: A growing body of evidence shows that childhood wheezing may lead to recurrent or persistent symptoms in adulthood, such that persistent wheezing associated with lung function deficits often have their roots in the first few years of life. Objectives: We summarized information from several prospective cohort studies following children with or without wheezing into adulthood, to estimate the effect of childhood wheezing on adulthood lung function. Methods: Medical literatures were searched in the Medline, PubMed, ScienceDirect, Web of Science and Embase databases up to October 31, 2016. The adulthood lung function was selected as primary outcome, and chronic obstructive pulmonary disease (COPD) prevalence was selected as secondary outcome. The meta-analysis was performed with the Stata Version 14.0. A random-effects model was applied to estimate standardized mean difference (SMD) of lung function, and relative risk (RR) of COPD. Results: Six articles enrolling 1141 and 1005 children with and without wheezing, respectively. Meta-analysis showed that childhood wheezing decreased adulthood lung function as compared with no-wheezing subjects (SMD = -0.365, 95% confidence interval (CI): -0.569~-0.161, P = 0.000). Subgroup analyses indicated that childhood atopic wheezing reduced adulthood FEV1/FVC and FEV1%pred when compared with no-wheezing subjects. In addition, childhood atopic wheezing was significantly associated with COPD prevalence (RR = 5.307, 95% CI:1.033~27.271, P = 0.046). Conclusions: Our meta-analysis suggests that childhood wheezing may induce ongoing declined lung function that extends into adult life, as well as an increased risk of COPD prevalence when accompanied with atopy. [ABSTRACT FROM AUTHOR]

The authors describe a composite material prepared from carbon nanohorns and poly(2-aminopyridine) that was obtained by electrochemical polymerization of 2-aminopyridine on carbon nanohorns. The material was used to modify a glassy carbon electrode (GCE) to obtain a sensor for non-enzymatic determination of hydrogen peroxide. The modified GCE was characterized by cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometry. The modified electrode is shown to display excellent electrical conductivity and catalytic activity towards hydrogen peroxide, mainly due to the large specific surface area of carbon nanohorns, the good electron charge transfer properties resulting from the use of poly(2-aminopyridine), and their synergistic effect. The response of the modified GCE (best operated at a working potential of −0.45 V vs. SCE) to HO is linear in the 0.05 to 8 mM concentration range. The limits of detection (LOD) and quantitation (LOQ) are 3.6 μM and 12.4 μM, respectively. The electrode is selective, stable and reproducible, this making it a promising tool for non-enzymatic determination of hydrogen peroxide. [ABSTRACT FROM AUTHOR]

Novel molybdenum disulfide nanosheets–decorated polyaniline (MoS 2 /PANI) was synthesized and investigated as an efficient catalyst for hydrogen evolution reaction (HER). Compared with MoS 2 , MoS 2 /PANI nanocomposites exhibited higher catalytic activity and lower Tafel slope for HER in H 2 SO 4 solution. The amount of 19 wt% PANI for coupling with MoS 2 resulted in a high current density of 80 mA cm −2 at 400 mV (vs. RHE). In addition, the optimal MoS 2 /PANI nanocomposite showed impressive long-term stability even after 500 cycles. The enhanced catalytic activity of MoS 2 /PANI nanocomposites was primarily ascribed to the effective electron transport channels of PANI and the increase of electrochemically accessible surface area in composite materials, which was advantageous to facilitate the charge transfer at catalyst/electrolyte interface. [ABSTRACT FROM AUTHOR]

Highlights: [•] Attapulgite was used as a template to control size and morphology of polyaniline. [•] Phosphomolybdic acid was stably anchored on attapulgite/PANI composite. [•] Attapulgite/PANI/PMo12/GCE showed perfect electrocatalytic activity to iodate. [•] Detection limit of attapulgite/PANI/PMo12/GCE for iodate was found to be 0.53μM. [Copyright &y& Elsevier]

Particulate matter (PM) has become the main air pollutant in most cities of in China, which greatly threatens the human health. Numerous studies have reported that PM concentrations could be accurately predicted from previous days' meteorological conditions. However, the hysteretic or lagged effects of meteorological factors on PM concentrations are not clear. In this study, the GeoDetector q statistic method was used to quantify the hysteretic influences of meteorological conditions and their interactions on concentrations of PM 2.5 (particles < 2.5 μm in aerodynamic diameter) and PM 10 (particles < 10 μm in aerodynamic diameter) and the ratio of PM 2.5 to PM 10 (PM 2.5 /PM 10) at multiple spatial and temporal scales in China. We found that the temperature, precipitation, and relative humidity had primary impacts on PM 2.5 concentrations, PM 10 concentrations, and the PM 2.5 /PM 10 ratios, respectively, at both national and annual time scales. At the seasonal time scale, precipitation and relative humidity had hysteretic effects on PM concentrations in spring and summer, respectively. Moreover, precipitation and wind speed were dominant hysteretic factors in autumn and winter, respectively. At the regional scale, the dominant hysteretic effects of meteorological factors showed large variations across all regional subdivisions. The interactions between any two meteorological factors had an enhanced hysteretic effect on PM concentrations compared to a single factor. These findings could help us to develop scientific measures to reduce the emissions of air pollution and improve the performance of air pollution prediction models. Image 1 • Hysteretic effects of meteorological factors on particulate matter were identified. • Temperature, rainfall, and humidity are main lagged factors of particulate matter. • Regional and seasonal variations of hysteretic factors were identified in China. • Urgent need to explore mechanisms of lagged effects of meteorological factors on PM. [ABSTRACT FROM AUTHOR]

Asthma is a major public health concern throughout the world. Numerous researches have shown that the spatial-temporal patterns of asthma are inconsistent, leading to the suggestion that these patterns are determined by multiple factors. This study aims to detect spatial-temporal clusters of asthma and analyze socio-ecological factors associated with the asthma hospitalization rate in Guangxi, China. Asthma hospitalization and socio-ecological data for 88 counties/municipal districts in Guangxi, China in 2015 was collected. Space-time scan statistics were applied to identify the high-risk periods and areas of asthma hospital admissions. We further used GeoDetector and Spearman correlation coefficient to investigate the socio-ecological factors associated with the asthma hospitalization rates. There were a total of 7804 asthma admissions in 2015. The high-risk period was from April to June. The age groups of 0–4 and ≥65 years were both at the highest risk, with hospital admission rates of 45.0/105 and 46.5/105, respectively. High-risk areas were found in central and western Guangxi with relative risk (RR) values of asthma hospitalizations greater than 2.0. GDP per capita and altitude were positively associated with asthma hospitalizations, while air pressure and wind speed had a negative association. The explanatory powers of these factors (i.e., GDP per capita, altitude, air pressure, wind speed) were 22%, 20%, 14% and 10%, respectively. The GDP per capita appears to have the strongest correlation with asthma hospitalization rates. High-risk areas were identified in central and western Guangxi characterized by high GDP per capita. These findings may be helpful for authorities developing targeted asthma prevention policies for high-risk areas and vulnerable populations, especially during high-risk periods. • In Guangxi, the high-risk period for asthma was from April to June. • Age groups of 0–4 and ≥65 years were at the highest risk. • Hotspots were mainly found in central and western Guangxi where the GDP per capita was high. • GDP per capita played an important role in asthma, which was positively correlated with asthma hospitalization rate. • GeoDetector is suitable for detecting risk factors of disease. [ABSTRACT FROM AUTHOR]