RESUMO
Classifying individuals with neurological disorders and healthy subjects using EEG is a crucial area of research. The current feature extraction approach focuses on the frequency domain features in each of the EEG frequency bands and functional brain networks. In recent years, researchers have discovered and extensively studied stability differences in the electroencephalograms (EEG) of patients with neurological disorders. Based on this, this paper proposes a feature descriptor to characterize EEG instability. The proposed method starts by forming a signal point cloud through Phase Space Reconstruction (PSR). Subsequently, a pseudo-metric space is constructed, and pseudo-distances are calculated based on the consistent measure of the point cloud. Finally, Distance to Measure (DTM) Function are generated to replace the distance function in the original metric space. We calculated the relative distances in the point cloud by measuring signal similarity and, based on this, summarized the point cloud structures formed by EEG with different stabilities after PSR. This process demonstrated that Multivariate Kernel Density Estimation (MKDE) based on a Gaussian kernel can effectively separate the mappings of different stable components within the signal in the phase space. The two average DTM values are then proposed as feature descriptors for EEG instability.In the validation phase, the proposed feature descriptor is tested on three typical neurological disorders: epilepsy, Alzheimer's disease, and Parkinson's disease, using the Bonn dataset, CHB-MIT, the Florida State University dataset, and the Iowa State University dataset. DTM values are used as feature inputs for four different machine learning classifiers, and The results show that the best classification accuracy of the proposed method reaches 98.00 %, 96.25 %, 96.71 % and 95.34 % respectively, outperforming commonly used nonlinear descriptors. Finally, the proposed method is tested and analyzed using noisy signals, demonstrating its robustness compared to other methods.
Assuntos
Eletroencefalografia , Doenças do Sistema Nervoso , Processamento de Sinais Assistido por Computador , Humanos , Eletroencefalografia/métodos , Doenças do Sistema Nervoso/fisiopatologia , Algoritmos , Feminino , MasculinoRESUMO
In the work, the 1/2 order subharmonic wave of two coupling cavitation bubbles is investigated numerically via Fourier spectrum analysis. By analyzing the dynamics of bubble, we find that the mutual interaction between bubbles can affect the appearance of 1/2 order subharmonic. The results of parameter dependence show that the intensity of 1/2 order subharmonic would be promoted or inhibited with the increase of mutual interaction. The higher the driving amplitude or the smaller the distance between bubbles, the stronger the mutual interaction is, and also the greater the promotion or suppression of the 1/2 order subharmonic is. Moreover, while the 1/2 order subharmonic occurs, the energy of bubble would alternate between two different peaks, and the temperature inside bubble has a similar fluctuation while the bubble collapses. This qualitative analysis suggests that the bubble's dynamics for multi-bubble case is complex. Understanding the generation of subharmonic of bubble's dynamics is of great significance for helpful applying of cavitation bubble.
RESUMO
This study aimed to investigate the predictive value of advanced lung cancer inflammation index (ALI) for major adverse cardiovascular events (MACEs) in elderly patients with acute coronary syndrome (ACS).A total of 586 ACS patients undergoing percutaneous coronary intervention (PCI) over 65 years old between January 2017 and December 2018 were retrospectively collected. The patients were divided into two groups by the optimal cutoff value of ALI. Spearman rank correlation coefficient was used to evaluate the correlation between ALI and the Global Registry of Acute Coronary Events (GRACE). Time-dependent receiver operating characteristic (ROC) curves, Cox survival analysis, and Kaplan Meier curves were used to assess the predictive value of ALI for MACEs.Spearman's nonparametric test revealed a moderate correlation between ALI and the GRACE (r: -0.417, P < 0.001). Time-dependent ROC curves showed that the area under the curve for ALI was 0.751 (95% CI, 0.699-0.798) in predicting MACEs, higher than Geriatric Nutritional Risk Index (0.531, 95% CI 0.435-0.627) and Prognostic Nutritional Index (0.590, 95% CI 0.505-0.676), and for combined diagnostic models (ALI + GRACE) was 0.913, (95% CI 0.875 - 0.942, P < 0.001). Multivariate Cox analysis demonstrated that ALI (HR: 0.974, 95% CI: 0.952-0.996, P = 0.017) was an independent risk factor for MACEs. Kaplan Meier survival analysis showed that the cumulative incidence of MACEs was significantly higher in elderly ACS patients with lower ALI (log-rank test, P < 0.001).ALI could be a nutrition-inflammation indicator with independent predictive value for long-term MACEs of elderly ACS patients after PCI.
Assuntos
Síndrome Coronariana Aguda , Intervenção Coronária Percutânea , Humanos , Síndrome Coronariana Aguda/mortalidade , Síndrome Coronariana Aguda/terapia , Síndrome Coronariana Aguda/complicações , Idoso , Masculino , Feminino , Estudos Retrospectivos , Prognóstico , Inflamação , Idoso de 80 Anos ou mais , Curva ROC , Valor Preditivo dos Testes , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/patologia , Medição de Risco/métodos , Estimativa de Kaplan-MeierRESUMO
Here, we have synthesized six dihydroxyl-functionalized ionic liquids for phase behavior studies at low temperature via crystallographic methods, Raman spectroscopy, differential scanning calorimetry (DSC), and density functional theory (DFT) calculations. Phase varieties are observed depending on the direction and strength of hydrogen bonding. Our studies also show that the ILs could be potentially excellent phase-change thermal storage materials with nearly no change of the phase transition enthalpy.
RESUMO
BACKGROUND AND AIM: The TyG index has been linked with cardiometabolic diseases. Our study aimed to investigate the specific relationship between the triglyceride and glucose index (TyG) and both all-cause and cardiovascular mortality in diabetic patients. METHODS AND RESULTS: We enrolled 3120 participants with diabetes from the National Health and Nutrition Examination Survey. The TyG index was calculated using the formula ln [fasting triglycerides (mg/dL) × fasting glucose (mg/dL)/2]. Hazard ratios (HRs) of TyG associated with mortality risk were assessed using Cox proportional hazard regression models. Over a follow-up period of 10.8 thousand person-years, we observed 768 all-cause deaths and 155 cardiovascular deaths. Compared to the reference quartile, the multivariate-adjusted hazard ratios and 95% confidence intervals for all-cause mortality were 1.02 (1.01-1.05; p = 0.008) in the fourth quartile. Dose-response analysis revealed a non-linear association. However, no significant associations were found between the TyG index and cardiovascular mortality. CONCLUSIONS: The TyG index exhibited a non-linear association with the risk of all-cause mortality in diabetic patients.
Assuntos
Biomarcadores , Glicemia , Causas de Morte , Diabetes Mellitus , Inquéritos Nutricionais , Triglicerídeos , Humanos , Masculino , Feminino , Triglicerídeos/sangue , Pessoa de Meia-Idade , Glicemia/metabolismo , Medição de Risco , Biomarcadores/sangue , Diabetes Mellitus/sangue , Diabetes Mellitus/mortalidade , Diabetes Mellitus/diagnóstico , Idoso , Fatores de Tempo , Prognóstico , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico , Adulto , Fatores de Risco , Valor Preditivo dos TestesRESUMO
Phosphor-in-glass represents a promising avenue for merging the luminous efficiency of high-quality phosphor and the thermal stability of a glass matrix. Undoubtedly, the glass matrix system and its preparation are pivotal factors in achieving high stability and preserving the original performance of embedded phosphor particles. In contrast to the well-established commercial Y3Al5O12:Ce3+ oxide phosphor, red nitride phosphor, which plays a critical role in high-quality lighting, exhibits greater structural instability during the high-temperature synthesis of inorganic glasses. A telluride glass with a refractive index (RI = 2.15@615 nm) akin to that of nitride phosphor (â¼2.19) has been devised, demonstrating high efficiency in photon utilization. The lower glass-transition temperature plays a crucial role in safeguarding phosphor particles against erosion resulting from exposure to high-temperature melts. Phosphor-in-glass retains 93% of the quantum efficiency observed for pure phosphor. The assembled white light-emitting diodes module has precise color tuning capabilities, achieving an optimal color rendering index of 93.7, a luminous efficacy of 80.4 lm/W, and a correlated color temperature of 5850 K. These outcomes hold potential for advancing the realm of inorganic package and high-quality white light illumination.
RESUMO
Capacity-limited visual working memory (VWM) requires that individuals have sufficient memory space and the ability to filter distractors. Negative emotional states are known to impact VWM storage, yet their influence on distractor filtering within VWM remains underexplored. We conducted direct neural measurement of participants (n = 56) who conducted a lateralized change detection task with distractors, while manipulating the emotional state by presenting neutral or negative images before each trial. We found a detrimental effect of distractors on memory accuracy under both neutral and negative emotional states. Using the event-related potential (ERP) component, contralateral delay activity (CDA; sensitive to VWM load), to observe the VWM load in each condition, we found that in the neutral state, the participants showed significantly higher late CDA amplitudes when remembering 4 targets compared with 2 targets and 2 targets with 2 distractors but no significant difference when remembering 2 targets compared with 2 targets with 2 distractors. In the negative state, no significant CDA amplitude differences were evident when remembering 4 targets and 2 targets, but CDA was significantly higher when remembering 2 targets with 2 distractors compared with 2 targets. These results suggest that the maximum number of items participants could store in VWM was lower under negative emotional states than under neutral emotional states. Importantly, the participants could filter out distractors when in a neutral emotional state but not in a negative emotional state, indicating that negative emotional states impair their ability to filter out distractors in VWM.
Assuntos
Eletroencefalografia , Emoções , Potenciais Evocados , Memória de Curto Prazo , Humanos , Feminino , Masculino , Memória de Curto Prazo/fisiologia , Emoções/fisiologia , Adulto Jovem , Potenciais Evocados/fisiologia , Adulto , Atenção/fisiologia , Encéfalo/fisiologia , AdolescenteRESUMO
Space-based gravitational wave detection missions use multiple satellites to form a very large scale Michelson laser interferometer in space. This requires extremely high precision displacement measurements at the picometer level between test masses even millions of kilometers apart. Drag-free control is a key technology to ensure the ultra-static and ultra-stable space experiment platform for space-based gravitational wave detection. This paper proposes an innovative ground simulation scheme for drag-free control principle based on the Stewart platform. The kinematics and dynamics modeling of the Stewart platform used in the experiment is presented. A drag-free ground simulation experimental equipment is designed and built. A two-degree-of-freedom (2-DOF) drag-free controller is designed based on the H∞ loop shaping algorithm which outperforms a PID controller in Simulink simulation. A semi-physical simulation experiment is conducted to verify the controller designed using rapid control prototyping technology. The experimental results show that the control performance reaches the limit accuracy of the hardware device, thus verifying the effectiveness of the drag-free control algorithm.
RESUMO
A green phosphor Sr2 ZnGe2 O7 :Mn2+ with a melilite structure was prepared using a high-temperature solid-state reaction. When the 535 nm emission was monitored, the excitation spectrum of the Sr2 ZnGe2 O7 :Mn2+ was found to contain two excitation bands in the ultraviolet (UV) region. When excited by UV light, the sample shows bright green emission at 535 nm, which corresponds to the distinctive transition of Mn2+ (4 T1 â6 A1 ). Moreover, the quantum efficiency of Sr2 ZnGe2 O7 :Mn2+ could reach 67.6%. Finally, a high-performance white-light-emitting diode (WLED) with a low correlated colour temperature of 4632 K and a high colour rendering index (CRI) of 92.3 were packaged by coating commercial blue and red phosphors with an optimized Sr2 ZnGe2 O7 :Mn2+ sample on a 310 nm UV chip. This indicated that Sr2 ZnGe2 O7 :Mn2+ has the potential application as a green component in the WLED lighting field.
Assuntos
Substâncias Luminescentes , Substâncias Luminescentes/química , Luz Verde , Luminescência , Raios UltravioletaRESUMO
In a plane acoustic field, a model involving the radial and translational motions of bubble is derived, which is used to numerically investigate the translation of two interacting spherical cavitation bubbles. For the smaller initial distance between bubble centers, we investigate the dynamics of two bubbles, and find that they could come into contact but the velocities of closing to each other are different when the equilibrium radius is different. The results show that when the wavelength of plane acoustic field is much larger than the initial distance, the bubbles are approximately pulsating in phase. Moreover, the velocity of contact process of two bubbles can be changed by adjusting the parameters of plane acoustic field. For increasing in the initial distance, the bubbles would present two translation motions: close to each other for the pulsating in phase and away from each other for the pulsating out of phase, which could be verified by calculating the secondary Bjerknes force. Meanwhile, the larger the initial distance, the smaller the secondary Bjerknes force value is. Understanding the translation of bubble is of great significance for helpful explaining formation of streamer structures in ultrasonic cavitation.
RESUMO
Space-borne gravitational wave detection satellite confronts many uncertain perturbations, such as solar pressure, dilute atmospheric drag, etc. To realize an ultra-static and ultra-stable inertial benchmark achieved by a test-mass (TM) being free to move inside a spacecraft (S/C), the drag-free control system of S/C requires super high steady-state accuracies and dynamic performances. The Active Disturbance Rejection Control (ADRC) technique has a certain capability in solving problems with common perturbations, while there is still room for optimization in dealing with the complicated drag-free control problem. When faced with complex noises, the steady-state accuracy of the traditional control method is not good enough and the convergence speed of regulating process is not fast enough. In this paper, the optimized Active Disturbance Rejection Control technique is applied. With the extended state Kalman filter (ESKF) estimating the states and disturbances in real time, a novel closed-loop control structure is designed by combining the linear quadratic regulator (LQR) and ESKF, which can satisfy the design targets competently. The comparative analysis and simulation results show that the LQR controller designed in this paper has a faster response and a higher accuracy compared with the traditional nonlinear state error feedback (NSEF), which uses a deformation of weighting components of classical PID. The new drag-free control structure proposed in the paper can be used in future gravitational wave detection satellites.
RESUMO
The interaction between spherical cavitation bubble and flat wall is transformed into that between the real bubble and imaging bubble by the method of images. Firstly, we investigate the dynamics of real bubble and matched, inversed or mis-matched imaging bubble driven by a small amplitude ultrasound, revealing the characteristics of the interaction between cavitation bubble and rigid, soft and impedance walls. Then, we emphatically study the dynamics of real bubble and mis-matched imaging bubble driven by a finite amplitude ultrasound, and the interaction characteristics between cavitation bubble and real impedance wall are revealed. The results show that the cavitation bubble is always close to the rigid wall and far away from the soft wall; For the impedance wall, whether the cavitation bubble is far away or close depends on the specific wall parameters. Moreover, the direction and magnitude of bubble's translation velocity can be changed by adjusting the driving parameters. Understanding the interaction between cavitation bubble and impedance wall is of great significance for efficient application of ultrasonic cavitation.
RESUMO
The mitogen-activated protein kinase kinase kinase 18 (MAPKKK18) has been reported to play a role in abiotic stress priming in long-term abscisic acid (ABA) response including drought tolerance and leaf senescence. However, the upstream transcriptional regulators of MAPKKK18 remain to be determined. Here, we report ABA-responsive element binding factors (ABFs) as upstream transcription factors of MAPKKK18 expression. Mutants of abf2, abf3, abf4, and abf2abf3abf4 dramatically reduced the transcription of MAPKKK18. Our electrophoresis mobility shift assay and dual-luciferase reporter assay demonstrated that ABF2, ABF3, and ABF4 bound to ABA-responsive element cis-elements within the promoter of MAPKKK18 to transactivate its expression. Furthermore, enrichments of the promoter region of MAPKKK18 by ABF2, ABF3, and ABF4 were confirmed by in vivo chromatin immunoprecipitation coupled with quantitative PCR. In addition, we found that mutants of mapkkk18 exhibited obvious delayed leaf senescence. Moreover, a genetic study showed that overexpression of ABF2, ABF3, and ABF4 in the background of mapkkk18 mostly phenocopied the stay-green phenotype of mapkkk18 and, expression levels of five target genes of ABFs, that is, NYE1, NYE2, NYC1, PAO, and SAG29, were attenuated as a result of MAPKKK18 mutation. These findings demonstrate that ABF2, ABF3, and ABF4 act as transcription regulators of MAPKKK18 and also suggest that, at least in part, ABA acts in priming leaf senescence via ABF-induced expression of MAPKKK18.
Assuntos
Ácido Abscísico , Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Folhas de Planta , Senescência Vegetal , Elementos Reguladores de Transcrição , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , MAP Quinase Quinase Quinases/metabolismo , Senescência Vegetal/genética , Senescência Vegetal/fisiologia , Plantas Geneticamente Modificadas/metabolismo , Fatores de Transcrição/metabolismo , Folhas de Planta/genética , Folhas de Planta/fisiologiaRESUMO
BACKGROUND: Pain can have a significant impact on an individual's life, as it has both cognitive and affective consequences. However, our understanding of how pain affects social cognition is limited. Previous studies have shown that pain, as an alarm stimulus, can disrupt cognitive processing when focal attention is required, but whether pain also affects task-irrelevant perceptual processing remains unclear. METHODS: We examined the effect of laboratory-induced pain on event-related potentials (ERPs) to neutral, sad and happy faces before, during and after a cold pressor pain. ERPs reflecting different stages of visual processing (P1, N170 and P2) were analysed. RESULTS: Pain decreased the P1 amplitude for happy faces and increased the N170 amplitude for happy and sad faces compared to the pre-pain phase. The effect of pain on N170 was also observed in the post-pain phase. The P2 component was not affected by pain. CONCLUSIONS: Our results suggest that pain alters both featural (P1) and structural face-sensitive (N170) visual encoding of emotional faces, even when the faces are irrelevant to the task. While the effect of pain on initial feature encoding seemed to be disruptive and specific to happy faces, later processing stages showed long-lasting and increased activity for both sad and happy emotional faces. SIGNIFICANCE: The observed alterations in face perception due to pain may have consequences for real-life interactions, as fast and automatic encoding of facial emotions is important for social interactions.
Assuntos
Eletroencefalografia , Expressão Facial , Eletroencefalografia/métodos , Emoções/fisiologia , Encéfalo , Potenciais Evocados/fisiologiaRESUMO
Face anti-spoofing (FAS) has lately attracted increasing attention due to its vital role in securing face recognition systems from presentation attacks (PAs). As more and more realistic PAs with novel types spring up, early-stage FAS methods based on handcrafted features become unreliable due to their limited representation capacity. With the emergence of large-scale academic datasets in the recent decade, deep learning based FAS achieves remarkable performance and dominates this area. However, existing reviews in this field mainly focus on the handcrafted features, which are outdated and uninspiring for the progress of FAS community. In this paper, to stimulate future research, we present the first comprehensive review of recent advances in deep learning based FAS. It covers several novel and insightful components: 1) besides supervision with binary label (e.g., '0' for bonafide versus '1' for PAs), we also investigate recent methods with pixel-wise supervision (e.g., pseudo depth map); 2) in addition to traditional intra-dataset evaluation, we collect and analyze the latest methods specially designed for domain generalization and open-set FAS; and 3) besides commercial RGB camera, we summarize the deep learning applications under multi-modal (e.g., depth and infrared) or specialized (e.g., light field and flash) sensors. We conclude this survey by emphasizing current open issues and highlighting potential prospects.
RESUMO
This paper studies the simplest system that can possess left-right symmetrical and asymmetrical surroundings, three bubbles in a line. Assuming that the deformations are small, the surfaces of bubbles are described by a combination of the first three Legendre polynomials, that is, spherical symmetrical mode P0, L-R antisymmetrical mode P1, and symmetrical mode P2. A dynamical model is built to describe aspherical oscillations of central and two side bubbles. It is found that when three identical bubbles are separated uniformly, the central bubble only has a P2 component and P1 component tends to zero, while two side bubbles have both P1 and P2 components. When three identical bubbles are separated by different distances, they can be degenerated into a two-bubble system and a free bubble. The bubble deformations contain both P1 and P2 components in the two-bubble system, while both aspherical components P1 and P2 of the free bubble tend to zero. If side bubbles are different in ambient radii but located symmetrically on the left and right of the central bubble, the side bubble pulsated more strongly plays an important role on the deformation of the central one.
RESUMO
Layered bismuth oxychalcogenides have been demonstrated as potential candidates for high-speed and low-power electronics due to their outstanding environmental stability and high carrier mobility, but the photoelectric performance of bulk species is still far from satisfactory. Herein, a novel Bi9O7.5S6/CdS composite film with a type-II heterojunction has been successfully prepared by combining chemical bath deposition (CBD) and spin-coating technologies. The structure, morphology, optical and photoelectric properties of the samples were investigated systematically. The photoelectric current of the Bi9O7.5S6/CdS composite film was obtained as 32.49 µA cm-2 at 1 V, which is about 13.9-fold and 3.3-fold higher than those of bare Bi9O7.5S6 and CdS. An enhanced photoelectric response and photostability were achieved in the Bi9O7.5S6/CdS composite film, and can be appropriately attributed to the improved separation and transfer of photogenerated carriers driven by the type-II heterojunction. This work offers a promising route to develop high-performance visible-light photoelectric devices with type-II heterojunctions.
RESUMO
INTRODUCTION: Early onset sepsis (EOS) remains a potentially fatal newborn condition, especially in very preterm infants. Data on the pathogen distribution and antibiotic susceptibility patterns of EOS among very preterm infants are scarce but essential for the choice of empirical antibiotic administration. We sought to assess the epidemiologic characteristics and antibiotic susceptibility patterns of pathogens causing EOS among a cohort of very preterm infants in China. METHODS: This prospective, observational study included a cohort of infants born at a gestational age (GA) less than 32 weeks of 32 newborn intensive care units (NICUs) in China between January 1, 2018 and December 31, 2020. EOS was defined by isolation of pathogenic species from blood culture within 72 h of birth. RESULTS: A total of 108 EOS cases (18.4 per 1000 admissions) were identified among 5865 very preterm infants. Incidence of EOS increased with the decrease of GA and birthweight. Escherichia coli (n = 44, 40.7%) was the most common pathogen, followed by Klebsiella spp. (n = 10, 9.3%). The distribution and proportion of pathogenic bacteria varied significantly by GA. E. coli and Klebsiella spp. showed high resistance to ampicillin and third-generation cephalosporins, while they showed good susceptibility to carbapenem antibiotics and piperacillin-tazobactam. CONCLUSION: Our data demonstrated that pathogens causing neonatal EOS showed high rates of resistance to ampicillin and third-generation cephalosporins. This raised questions about the best empirical antibiotic choice for preterm infants suspected of having EOS in low- and middle-income countries (LMICs).
RESUMO
OBJECTIVES: To investigate the risk profile of preterm birth (PTB) in 2018 in China. METHOD: A prospective multicentre case-control study was conducted in 15 hospitals located in seven provinces throughout three geographical areas (the Eastern, South-Central and North-Western regions) in China. A total of 3147 preterm (<37+0 weeks) and 3147 term (37+0 to 41+6 weeks) live-birth mothers were included. Designed questionnaires were used to investigate maternal and fetal information. We calculated multivariable logistic regression and population attributable risk (PAR). RESULTS: Iatrogenic PTB accounted for 48.1% of preterm mothers. Multivariable analysis showed PTB was significantly associated with six categories of maternal and fetal factors, adverse life-style and psychological conditions (adjusted odds ratio (aOR) 2.063, 95% confidence interval (CI) 1.601-2.657) had the highest PAR% (60.1%). High school and below education level (PAR% = 25.8%), living in town or village (PAR% = 24.4%), low pregnant weight gain (PAR% = 16.8%), hypertensive disorders in pregnancy (aOR: 5.010, 95% CI: 4.039-6.216, PAR% = 15.3%), placental abnormality (aOR: 4.242, 95% CI: 3.454-5.211, PAR% = 14.1%) and multiple pregnancy (aOR: 10.990, 95% CI: 7.743-15.599, PAR% = 11.8%) were significantly associated with PTB with high PAR% value. CONCLUSION: The main risk factors for PTB in China were placental abnormality, hypertensive disorders in pregnancy and multiple pregnancy. Adverse life-style and psychological conditions and socio-economic disadvantage had high public health significance.
Assuntos
Hipertensão Induzida pela Gravidez , Nascimento Prematuro , Estudos de Casos e Controles , China/epidemiologia , Feminino , Humanos , Recém-Nascido , Placenta , Gravidez , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , Estudos Prospectivos , Fatores de Risco , Inquéritos e QuestionáriosRESUMO
Purpose: Significant antibiotic overuse due to prolonged antibiotic duration has not draw enough attention in developing countries with high antibiotic consumption. We aimed to describe the current status of prolonged early antibiotic duration in very-low-birth-weight (VLBW) infants in a large regional multicenter cohort in China. Patients and Methods: Institution-based prospective cohort study was conducted in all VLBW infants admitted to 16 Grade A tertiary hospitals between January 1, 2019 and December 31, 2020. Early antibiotic use was defined as antibiotic initiation within the first 3 days of life. Prolonged early antibiotic course was defined as early antibiotic initiation for more than 7 days in infants with early-onset sepsis (EOS) or more than 3 days in infants with unlikely EOS. Antibiotic use was described as days of therapy (DOT) per 1000 patient days (PD). Results: Among 1684 eligible VLBW infants, 1544 (91.7%) infants were prescribed with prolonged early antibiotic course, including 618 infants with EOS and 926 infants with unlikely EOS. The median duration of early antibiotic course was 13 (IQR 8;20) days, with 78.0% of courses >7 days and 43.6% of courses >14 days. Total early antibiotic use was 408.3DOT/1000Pd, of which prolonged antibiotic courses accounted for 98.2% of all antibiotic use days. More than three antibiotics used, escalation antibiotic therapy, antibiotics for special use and the use of third generation cephalosporins and carbapenems were significantly common in prolonged courses compared to short courses in both infants with EOS and unlikely EOS group (P<0.05). Conclusion: A large proportion of VLBW infants had excessively prolonged early antibiotic durations in the regional multicenter in China. Timely discontinuation of antibiotics in VLBW infants according to standardized guidelines and limit on the use of third-generation cephalosporins and carbapenems may be key drivers in reducing the antibiotic overuse in developing countries like ours.