Summary
What is known and objective
Vancomycin is one of the most widely used antibiotics for treating serious Gram‐positive infections in children. Few clinical studies have examined the potential ...risk factors for treatment failure in children receiving vancomycin. The objectives of this study were to evaluate the relationships between vancomycin trough concentration and treatment outcomes in Chinese paediatric patients with suspected Gram‐positive infections and to identify baseline characteristics that may affect treatment failure associated with vancomycin use.
Methods
A retrospective cohort study was conducted from April 2007 to October 2015. Patients were included in this study if they were <18 years old, had received vancomycin for at least 72 h and had at least one bacterial culture and one serum steady‐state vancomycin trough concentration. Treatment outcomes were defined as success or failure. Nephrotoxicity was defined as a serum creatinine (Scr) increase ≥44·2 μmol/L or a ≥50% increase in baseline Scr for at least two consecutive days. Univariate and multivariate logistic regression analyses were performed to identify risk factors for treatment failure with vancomycin.
Results and discussion
One hundred and eighty‐two patients were included. Vancomycin treatment failure occurred in 52 patients (28·6%), and the incidence of nephrotoxicity was low. No significant difference was observed in the vancomycin trough concentrations between the treatment success and failure groups. Multivariate logistic regression analyses showed that the vancomycin trough concentration odds ratio (OR), 1·046; 95% confidence interval (CI), 0·979–1·118; P = 0·179, statistical power: 62·04%) was not associated with treatment outcome, and only intensive care unit (ICU) admission (OR, 3·808; 95% CI, 1·714–8·465; P = 0·001, statistical power: 90·40%) was found to be independently associated with vancomycin treatment failure.
What is new and conclusion
Our findings suggest that the vancomycin trough concentration is not associated with treatment outcome. ICU admission is an independent predictor of treatment failure.
Our findings suggest that the vancomycin trough concentration is not associated with treatment outcome. Intensive care unit (ICU) admission is an independent predictor of treatment failure.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
This paper presents a unified framework of fault diagnosis and fault-tolerant cooperative output regulation (FTCOR) for a linear discrete-time multi-vehicle system with sensor faults. The FTCOR ...control law is designed through three steps. A cooperative output regulation (COR) controller is designed based on the internal mode principle when there are no sensor faults. A sufficient condition on the existence of the COR controller is given based on the discrete-time algebraic Riccati equation (DARE). Then, a decentralised fault diagnosis scheme is designed to cope with sensor faults occurring in followers. A residual generator is developed to detect sensor faults of each follower, and a bank of fault-matching estimators are proposed to isolate and estimate sensor faults of each follower. Unlike the current distributed fault diagnosis for multi-vehicle systems, the presented decentralised fault diagnosis scheme in each vehicle reduces the communication and computation load by only using the information of the vehicle. By combing the sensor fault estimation and the COR control law, an FTCOR controller is proposed. Finally, the simulation results demonstrate the effectiveness of the FTCOR controller.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray ...observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9} GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
Statins, the inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, are widely used cholesterol-lowering drugs. Convincing evidence indicates that statins stimulate apoptotic cell ...death in several types of proliferating tumor cells in a cholesterol-lowering-independent manner. The objective here was to elucidate the molecular mechanism by which statins induce lymphoma cells death. Statins (atorvastatin, fluvastatin and simvastatin) treatment enhanced the DNA fragmentation and the activation of proapoptotic members such as caspase-3, PARP and Bax, but suppressed the activation of anti-apoptotic molecule Bcl-2 in lymphoma cells including A20 and EL4 cells, which was accompanied by inhibition of cell survival. Both increase in levels of reactive oxygen species (ROS) and activation of p38 MAPK and decrease in mitochondrial membrane potential and activation of Akt and Erk pathways were observed in statin-treated lymphoma cells. Statin-induced cytotoxic effects, DNA fragmentation and changes of activation of caspase-3, Akt, Erk and p38 were blocked by antioxidant (N-acetylcysteine) and metabolic products of the HMG-CoA reductase reaction, such as mevalonate, farnesyl pyrophosphate (FPP) and geranylgeranyl pyrophosphate (GGPP). These results suggests that HMG-CoA reductase inhibitors induce lymphoma cells apoptosis by increasing intracellular ROS generation and p38 activation and suppressing activation of Akt and Erk pathways, through inhibition of metabolic products of the HMG-CoA reductase reaction including mevalonate, FPP and GGPP.
Abstract A Bayesian neural network (BNN) is developed to predict the 1st excitation energy of odd–odd nuclei. Aside from the proton number and neutron number, we introduce two empirical physical ...quantities into the input layer. δ = − 1 N + − 1 Z / 2 is introduced to distinguish even–even, odd–odd and odd-A nuclei; and the so-called Casten factor P ≡ v p v n v p + v n is introduced to stand for collectivity. The BNN is trained with an experimental dataset of the 1st excitation energy for 434 odd–odd, 649 even–even and 1050 odd-A nuclei. After training, the BNN predicts the 1st excitation energy of odd–odd nuclei with a rms of 0.21 MeV. Examples of Dy, Gd, Eu and Cs isotopes are also shown. The BNN results show moderate predictive ability, in comparison with results from the projected Hartree–Fock method.
The clinical value of increased levels of neutrophil gelatinase-associated lipocalin (NGAL) in patients with septic acute kidney injury (AKI) is still unclear. This study aimed to assess the link ...between illness severity and NGAL in patients with septic AKI.
This is a retrospective observational study that took place at the Fourth Hospital of Hebei Medical University, Shijiazhuang, China. The cohort included 365 patients who were admitted to the ICU during the 21-month period. Of them, 18 patients were diagnosed with sepsis (septic group). The average age of patients in the septic group was over 65, and 60.00% of them eventually progressed to septic AKI. Plasma NGAL (pNGAL) and urine NGAL (uNGAL) levels at defined time points were measured. AKI staging was done based on the Kidney Disease Improving Global Outcomes (KDIGO) classification. The Sequential Organ Failure Assessment (SOFA) and Acute Physiology and Chronic Health Evaluation (APACHE) II scores were determined. Patterns and associations between NGAL levels with SOFA scores and different stages of septic AKI were investigated.
Both pNGAL and uNGAL showed a positive correlation with SOFA and proved to be reliable predictors of the same. Furthermore, the accuracy of severe sepsis (SOFA ≥ 8) was 0.67 for pNGAL and 0.66 for uNGAL. Real-time detection of pNGAL and uNGAL indicated that they were good biomarkers of severe septic AKI. Area under the receiver operating characteristic (AUROC) for pNGAL and uNGAL were 0.72 (0.69-0.85), and 0.83 (0.71-0.95), respectively. However, only patients with KDIGO 3 AKI presented significantly elevated levels of pNGAL (p < 0.05). Furthermore, the uNGAL level at each stage of septic AKI was higher than that of the non-AKI period (p < 0.01).
In patients with septic AKI, levels of NGAL correlated with SOFA. Levels of pNGAL were good predictors of severe kidney injury and uNGAL levels could detect mild stages of AKI.
Nitrogen-doped carbon microspheres (NCSs) were fabricated via a simple, fast and energy-saving microwave-assisted method followed by thermal treatment under an ammonia atmosphere. NCSs thermally ...treated at different temperatures were investigated as anode materials for lithium ion batteries (LIBs). The results show that NCSs treated at 900 °C exhibit a maximum reversible capacity of 816 mA h g(-1) at a current density of 50 mA g(-1) and preserve a capacity of 660 mA h g(-1) after 50 cycles, and even at a high current density of 1000 mA g(-1), a capacity of 255 mA h g(-1) is maintained. The excellent electrochemical performance of NCSs is due to their porous structure and nitrogen-doping. The present NCSs should be promising low-cost anode materials with a high capacity and good cycle stability for LIBs.
In this work, the relationship between the accumulation and release of elastic energy during the flow serrations of a bulk metallic glass (BMG) was investigated by use of 10 groups of specimens under ...varying mixed-mode (I/II) loading conditions. The findings have shown that both the elastic energy accumulation rates and load drops have significant variations, and the load drop data are more scattered than elastic energy accumulation rates. The large variations of load drops are intrinsic for BMGs, while the variations of elastic energy accumulation rates can be reduced to improve/control the plastic deformation of BMGs. Moreover, smaller elastic energy accumulation rates can result in smaller load drops, resulting from the formation of more shear-band intersections. The present work is of significance for understanding the underlying mechanisms of flow serrations of BMGs. It also suggests that more attention could be paid into the elastic energy accumulation process in order to uncover the plastic deformation mechanisms of BMGs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
ABSTRACT
GW190814 was reported during LIGO’s and Virgo’s third observing run with the most asymmetric component masses (an ∼23 M⊙ black hole and an ∼2.6 M⊙ compact object). Under the assumption that ...this event is a binary black hole (BBH) merger formed through the isolated binary evolution channel, we reanalyse the publicly released data of GW190814 with the modified astrophysical priors on the effective spin χeff, and further explore its formation history using detailed binary modelling. We show that GW190814 is likely to have been formed through the classical common envelope channel. Our findings show that the properties inferred using the modified astrophysical priors are consistent with those inferred by the uniform priors. With the newly inferred properties of GW190814, we perform detailed binary evolution of the immediate progenitor of the BBH (namely a close binary system composed of a BH and a helium star) in a large parameter space, taking into account mass-loss, internal differential rotation, supernova kicks, and tidal interactions between the helium star and the BH companion. Our findings show that GW190814-like events could be formed in limited initial conditions just after the common envelope phase: an ∼23 M⊙ BH and a helium star of MZamsHe ∼ 8.5 M⊙ at solar metallicity (∼ 7.5 M⊙ at 10 per cent solar metallicity) with an initial orbital period at around 1.0 d. Additionally, the inferred low spin of the secondary indicates that the required metallicity for reproducing GW190814-like events should not be too low (e.g. Z ≳ 0.1 Z⊙).
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