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Accurate localization of objects of interest in remote sensing images (RSIs) is of great significance for object identification, resource management, decision-making and disaster relief response. However, many difficulties, like complex backgrounds, dense target quantities, large-scale variations, and small-scale objects, which make the detection accuracy unsatisfactory. To improve the detection accuracy, we propose an Adaptive Adjacent Context Negotiation Network (A2CN-Net). Firstly, the composite fast Fourier convolution (CFFC) module is given to reduce the information loss of small objects, which is inserted into the backbone network to obtain spectral global context information. Then, the Global Context Information Enhancement (GCIE) module is given to capture and aggregate global spatial features, which is beneficial for locating objects of different scales. Furthermore, to alleviate the aliasing effect caused by the fusion of adjacent feature layers, a novel Adaptive Adjacent Context Negotiation network (A2CN) is given to adaptive integration of multi-level features, which consists of local and adjacent branches, with the local branch adaptively highlighting feature information and the adjacent branch introducing global information at the adjacent level to enhance feature representation. In the meantime, considering the variability in the focus of feature layers in different dimensions, learnable weights are applied to the local and adjacent branches for adaptive feature fusion. Finally, extensive experiments are performed in several available public datasets, including DIOR and DOTA-v1.0. Experimental studies show that A2CN-Net can significantly boost detection performance, with mAP increasing to 74.2% and 79.2%, respectively. [ABSTRACT FROM AUTHOR]

Background: Most studies support parafunctions play an important role in temporomandibular disorders (TMD), whereas the association between tooth wear and TMD remains controversial. Betel nut chewing as a parafunction is popular in South and Southeast Asia. We therefore investigated the association of severely worn dentition resulting from betel nut chewing with TMD. Methods: A cross-sectional analysis of 408 control participants (male: 380, female: 28, 43.62 ± 9.54 years) and 408 participants with betel nut chewing related severely worn dentition (male: 380, female: 28, 43.73 ± 8.93 years) who received dental and TMD checkup according to Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) in Health Management Center, Xiangya Hospital was performed. Betel nut chewing related severely worn dentition meant all the natural teeth had moderate to severe tooth wear [Tooth Wear Index (TWI) ≥ 2)] including ≥ 2 severe wear teeth (TWI ≥ 3) due to betel nut chewing. Multivariable logistic regression analysis was used. Results: After adjusting for age, gender, betel nut chewing related severely worn dentition, oral submucosal fibrosis, number of missing teeth, number of dental quadrants with missing teeth, visible third molar and orthodontic history, variables of age, gender and betel nut chewing related severely worn dentition were significant for overall TMD. Multivariable analysis showed betel nut chewing related severely worn dentition was significantly associated with intra-articular TMD [odds ratio and 95% confidence intervals: 1.689 (1.271–2.244), P = 0.001] in a betel nut chewing dose-dependent manner. Conclusion: Betel nut chewing related severely worn dentition was associated with intra-articular TMD. [ABSTRACT FROM AUTHOR]

This paper mainly studies the model design of a thin-film heat-flux sensor (TFHFS), and focuses on the comparison of three dynamic calibration methods. The primary motivation for studying this came from the urgent need for heat-flux dynamic measurements in extreme environments, and the one-sidedness of the dynamic performance evaluation of the corresponding TFHFS. The dynamic theoretical model of the TFHFS was originally established on the principle of a temperature gradient on the basis of a thermal radiation boundary. Then, a novel TFHFS sensor was developed, which can be used at temperatures above 880 °C and has a high sensitivity of 2.0 × 10−5 mV/(W/m2). It can function stably for long durations under a heat-flux density of 3 MW/m2. The steady-state, transient, and frequency calibration of a TFHFS were compared to comprehensively analyze the dynamic characteristics of the TFHFS. The steady-state response time measured by the step excitation method was found to be 0.978 s. The QR decomposition method was applied to the steady-state response experimental model construction, and the fitting degree of a second-order transfer function model obtained was 98.61%. Secondly, the transient response time of the TFHFS was 0.31 ms based on the pulse-excitation method. The transient relationship between the surface temperature and the heat flux, and the pulse-width dependence of the TFHFS transient response time were established. Surprisingly, the response frequency of the TFHFS, about 3000 Hz, was efficiently tested using the frequency response function (FRF), which benefitted from the harmonic characteristics of a periodic square-wave excitation signal. Finally, a comprehensive evaluation of the dynamic performance of the TFHFS was realized. [ABSTRACT FROM AUTHOR]

A sensitivity-amplifying optical fiber sensor using cascaded Sagnac interferometers (CSIs) was designed and experimentally demonstrated for the dual-parameter measurement of strain and temperature. The proposed CSIs sensor consisted of two Sagnac interferometers (SIs) in which two identical PANDA polarization-maintaining fibers (PMFs) for just slightly different lengths were inserted. An envelope with a period of 123.6 nm, which was amplified more than 10 times than the single SI, was observed in the interference spectrum. Experimental results showed that the strain sensitivity increased from 32.91 pm/μϵ for the single SI to 336 pm/μϵ for the CSIs, while the temperature sensitivity increased from −1.38 nm/°C for the single SI to −14.86 nm/°C for the CSIs, correspondingly. We also found that the envelope of the CSIs shifted in opposite directions when the longer or shorter PMF was selected as the sensing arm. Higher sensitivity could be realized by selecting longer PMF as the sensing arm. Our proposed CSIs sensor possesses the merits of simple structure, high sensitivity, low cost, and low hysteresis effect, which make it a competitive candidate for strain and temperature monitoring. [ABSTRACT FROM AUTHOR]

A high sensitivity plasmonic temperature sensor based on a side-polished photonic crystal fiber is proposed in this work. In order to achieve high sensitivity and high stability, the gold layer is coated on the side-polished photonic crystal fiber to support surface plasmon resonance. The mixture of ethanol and chloroform is used as the thermosensitive liquid. The performances of the proposed temperature sensor were investigated by the finite element method (FEM). Simulation results indicate that the sensitivity of the temperature sensor is as high as 7.82 nm/°C. It has good linearity (R 2 = 0.99803), the resolution of 1.1 Ă— 10âˆ'3 °C, and the amplitude sensitivity of 0.1008 °Câˆ'1. In addition, the sizes of the small air hole and polishing depth have little influence on the sensitivity. Therefore, the proposed sensor shows a high structure tolerance. The excellent performance and high structure tolerance of the sensor make it an appropriate choice for temperature measurement. [ABSTRACT FROM AUTHOR]

Medical imaging modalities, such as magnetic resonance imaging (MRI) and computerized tomography (CT), have allowed medical researchers and clinicians to examine the structural and functional features of the human body, thereby assisting the clinical diagnosis. However, due to the highly controlled imaging environment, the imaging process often creates noise, which seriously affects the analysis of the medical images. In this study, a medical imaging enhancement algorithm is presented for ankle joint talar osteochondral injury. The gradient operator is used to transform the image into the gradient domain, and fuzzy entropy is employed to replace the gradient to determine the diffusion coefficient of the gradient field. The differential operator is used to discretize the image, and a partial differential enhancement model is constructed to achieve image detail enhancement. Three objective evaluation indexes, namely, signal-to-noise ratio (SNR), information entropy (IE), and edge protection index (EPI), were employed to evaluate the image enhancement capability of the proposed algorithm. Experimental results show that the algorithm can better suppress noise while enhancing image details. Compared with the original image, the histogram of the transformed image is more uniform and flat and the gray level is clearer. [ABSTRACT FROM AUTHOR]

A dual-polarized photonic crystal fiber (PCF) sensor based on surface plasmon resonance (SPR) was proposed for measuring the refractive indexes (RIs) of liquids. A gold film and a liquid analyte were successively wrapped around the outer surface of the PCF to stimulate the external SPR effect, which greatly reduced the manufacturing difficulties, compared to depositing the gold film and filling the inner air holes of the PCF with liquid analyte. The performance of the proposed PCF sensor was numerically investigated using the finite-element method. The results show that the proposed PCF sensor can realize dual-polarized detection in the RI range of 1.36–1.42. The x and y polarization (X-P and Y-P) core modes were coupled to the X-P second-order and Y-P first-order surface-plasmon polariton modes, respectively. As the the RI of the analyte increased, the wavelength sensitivity increased and, as a result, maximum values of 15 900 nm RIU−1 for X-P and 16 900 nm RIU−1 for Y-P were achieved. Correspondingly, we obtained a maximum amplitude sensitivity of 2026.05 RIU−1 for X-P and 2102.65 RIU−1 for Y-P. In addition, the fabrication tolerance of the proposed PCF was increased to ±0.4 μm, which made the proposed PCF a favorable candidate for the detection of liquids. [ABSTRACT FROM AUTHOR]

A fiber/Ag-Cu films surface plasmon resonance (SPR) refractive index (RI) sensor composed of multimode fiber-no-core-fiber-multimode fiber (MMF-NCF-MMF) structure is designed. The sensing region length and Cu film deposition time of sensor are gradually optimized by the control variable method, which finally achieves the improvement of sensor properties. We experimentally compared the sensing performance of the fiber/Ag film and fiber/Ag-Cu films sensor. Experimental results show that the fiber/Ag-Cu films sensor has good linearity (R-square = 0.993), and its sensitivity is as high as 3957 nm/RIU in the refractive index detection range of 1.3328–1.3853, which is 1109 nm/RIU higher than the sensitivity of a conventional fiber/Ag film sensor. The sensor presented in this paper adopts the structure with composite metal film, which outperforms the common single-layer metal film in chemical stability such as oxidation resistance and mechanical hardness. Meanwhile, the SPR sensor with MMF-NCF-MMF structure has the advantages of convenient manufacture and compact structure. In conclusion, it can bestow a unique advantage in the field of biological detection or chemical analysis. [ABSTRACT FROM AUTHOR]

Abstract: Zirconacyclopentenes, which are easily prepared from alkynes and EtMgBr (or ethylene) and Cp2ZrCl2, reacted with oxalyl chloride in the presence of catalytic amount of CuCl to give cyclopentenones in high yields. The reaction was performed conveniently in one pot from alkynes, EtMgBr, oxalyl chloride, and Cp2ZrCl2. [Copyright &y& Elsevier]

Structure-based forest management is a scientific and easy-to-operate method for sustainable forest management. We analyzed the stand spatial structure of Larix principis-rupprechtii plantation under five reserve densities. The results indicated that with the decrease of densities after thinning, the average mingling degree and uniform angle index had an increasing tendency, but the amplitude was small. Most of the trees were in zero mix, and a few of them were in moderate, strong, and relatively strong mix; the horizontal distribution patterns were uniform or near-uniform random. The distribution of neighborhood comparison and opening degree changed with a fluctuant pattern, but thinning decreased the competitive intensities to some extent. A composite structure index (Ci) was established, based on the relative importance of the above four indicators, to evaluate the overall effect of thinning on stand structure characteristics. The findings showed that Ci increased with the increase of thinning intensity, that is, the stand spatial structure became more complex. This indicated that Ci may be a simple and rapid indicator to evaluate the overall effect of thinning on stand spatial structure within densities after thinning. [ABSTRACT FROM AUTHOR]

• An optical fiber sensor combining the Sagnac interference and modal interference was fabricated and experimentally investigated for the measurements of liquid level and strain. • A sensitivity of 525 pm/mm for liquid level detection, and 32 pm/με for strain detection were obtained. • This sensor has advantages of simple structure, high sensitivity and good accuracy, which is an ideal candidate of liquid level and strain simultaneous detection. An optical fiber sensor for the detections of strain and liquid level was experimentally investigated in this paper. This sensor was fabricated through cascading the Sagnac interference (SI) and multi-mode interference (MMI). A construction of single mode fiber-no core fiber-single mode fiber (SMF-NCF-SMF) was used to excite the MMI, while a section of 10.0 cm long Panda polarization maintaining fiber (PMF) was utilized to generate the polarization modes interference in the Sagnac loop. Two interference valleys corresponding to the MMI and SI appeared in the transmission spectrum and were utilized to detect the liquid level and strain, respectively. The measurement sensitivity of liquid level is higher than most of the reported sensors. This designed sensor could become a good candidate for the liquid level and strain detection owing to the simple structure, high sensitivity, and low hysteresis effect. [ABSTRACT FROM AUTHOR]

A narrowband dual-polarization filter based on photonic crystal fiber (PCF) with Au-Ag double-layer films is proposed. The cladding of PCF is composed of three layers of air holes, and Au-Ag double-layer films are coated on two symmetrical air holes to excite surface plasmon resonance (SPR) effect. The special mechanism of the Au-Ag double-layer films takes advantage of the narrower full width at half maximum (FWHM) of silver. On the other hand, gold is used to protect the silver from oxidation and improve the stability of the filter, and can also enhance SPR effect. The simulation results show that the dual-polarization filter with double-layer metal films has higher resonance absorption and better spectra than that with the single-layer metal film. When the thickness of the double-layer metal films is 22.5 nm (the thickness of silver film is 18 nm), the confinement loss of dual-polarization filter at 1430 nm is achieved to 64.08 dB/cm (y-pol core mode) and at 1530 nm is achieved to 37.26 dB/cm (x-pol core mode). The wavelength range of crosstalk (CT) greater than 20 dB and less than −20 dB are 1410–1450 nm and 1510–1550 nm for the device length of 10 mm, respectively. The CT is achieved 555.07 dB and −321.54 dB at the wavelength of 1430 nm and 1530 nm, respectively. These characteristics show that the filter has excellent performance, and will become a suitable candidate for a narrowband polarization filter. [ABSTRACT FROM AUTHOR]

In this paper, a dual-polarizated photonic crystal fiber filter (PCF) based on surface plasmon resonance (SPR) was proposed. Its polarization characteristics were numerically researched by finite element method (FEM). The results indicate that the polarization filtering of the filter be able to fulfill in dual communication bands of 1310 and 1550 nm. The confinement loss reaches 80,711.4 dB/m for the x polarization core mode at the wavelength of 1310 nm, while 46,614.5 dB/m for the y polarization core mode at the wavelength of 1550 nm. When the length of PCF is 2.5 mm, the extinction ratios of x and y polarization core modes can achieve 1705.27 and − 883.46 dB, respectively. For the communication windows of 1310 and 1550 nm, the filtering bandwidths can reach to 390 and 350 nm, respectively. These excellent characteristics are beneficial to the design and manufacture of filter devices. • A PCF dual windows polarization filter based on SPR is proposed. The square arrangement of air holes is easy to prepare. • The losses of the filter at dual windows can reach 80,711.4 dB/m and 46,614.5 dB/m. • When L PCF = 2.5 mm, the ER of the two orthogonal modes can reach 1705.27 and − 883.46 dB. The bandwidth can reach 390 nm and 350 nm. [ABSTRACT FROM AUTHOR]

• An ultrahigh-sensitive fiber-optic temperature sensor based on cascaded Sagnac interferometers with a nematic liquid crystal film was proposed and experimentally demonstrated. • The molecules of NLC film changed from isotropic to isotropic just by rotating the two single-mode patch cables without any orientation agent, electric, or magnetic devices. • Experimental results revealed that the temperature sensor based on the cascaded configuration showed an ultrahigh sensitivity of 43.13 nm/°C, which was amplified about 5 times contrast to a single Sagnac interferometer. We demonstrated an ultrasensitive fiber-optic temperature sensor based on cascaded Sagnac interferometers (CSIs). One of the Sagnac interferometers (SIs) consisted of a panda polarization-maintaining fiber (PMF) as the reference arm, while the other one contained two single-mode patch cables in a ferrule matching sleeve as the sensing arm, where a nematic liquid crystal (NLC) film was infiltrated into the micron-scale gap of the sleeve. In the sensing SI, the orientation of NLC film was induced by just rotating the two single-mode patch cables without any orientation agent, electric, or magnetic devices. Vernier effect was acquired by adjusting the thickness of NLC film. Experimental results revealed that the temperature sensitivity of the CSIs was up to 43.13 nm/°C, which was enhanced about 5 times compared to the single NLC SI. The designed optical fiber temperature sensor possessed the merits of compact structure, high stability, ultrahigh sensitivity, low hysteresis effect and high resolution, showing a promising application prospect in some scientific filed requiring accurate temperature measurement, such as biomolecules, medicine and other filed. [ABSTRACT FROM AUTHOR]

• A bubble microcavity in an ultra-thin core optical fiber was fabricated to form a Fabry-Perot interferometer. • The size of the bubble decreased gradually with further arc discharges, which was inverse to the reported literature. • The bubble microcavity in the ultra-thin core optical fiber showed a strain sensitivity of 2.08 pm/με and a gravity sensitivity of 2.908 nm/N in a large measurement range. • The bubble microcavity in the ultra-thin core optial fiber was insensitive to temperature and bending, which was benefit to avoid the cross influences. Recent progress in optical fiber sensors based on Fabry-Perot interferometers (FPIs) has achieved much attention. In this paper, we designed and fabricated an FPI sensor by building a bubble in an ultra-thin core optical fiber. The size of the bubble decreased gradually with further arc discharges, which was inverse to the bubble fabrication in standard single mode fibers and multimode fibers. The bubble microcavity in the ultra-thin core optical fiber demonstrated a strain sensitivity of 2.08 pm/με in the range of 0–5000 με and a gravity sensitivity of 2.908 nm/N in the range of 0–4.89 N with high linear responses. Meanwhile, the bubble microcavity sensor was insensitive to temperature and bending, which was benefit to avoid the cross influences. The FPI sensor based on a bubble microcavity in an ultra-thin core optical fiber possesses the properties of easy to fabricate, small size, robustness, and high sensitivity. [ABSTRACT FROM AUTHOR]

Statement of Problem: The association between unreplaced missing posterior teeth and migraine has not been sufficiently reported., Purpose: The purpose of this cross-sectional study was to investigate the relationships between unreplaced missing posterior teeth and migraine or severe headaches., Material and Methods: Data from the US National Health and Nutrition Examination Survey 1999-2004 on 12 662 participants aged between 20 and 85 years were analyzed. The survey produced complete data on dentition examination, dietary intakes, and self-reported migraine or severe headaches. Weighted multivariable logistic regression analyses were performed (α=.05)., Results: A total of 20.28% of the participants had migraine or severe headaches. After adjusting demographic, clinical, and dietary covariates, the total number of missing teeth was not significantly associated with migraine or severe headaches, and only having both anterior and posterior missing teeth was significantly associated with migraine or severe headaches. The odds ratio (OR) and confidence interval (CI) was 1.32(1.09, 1.60) (P=.007). A significantly positive correlation was found between the number of unreplaced missing teeth and migraine or severe headaches. An increase of 1 in the number of unreplaced missing teeth was associated with a 3% increase in migraine or severe headaches (OR and CI: 1.03(1.01, 1.06), P=.012). However, no significant relationship was found between replaced missing teeth and migraine or severe headaches (OR and CI: 1.00(0.99, 1.01), P=.800). Furthermore, unreplaced missing posterior teeth and both unreplaced anterior and posterior teeth were significantly related with more migraine or severe headaches, but no significant association of unreplaced teeth was found with migraine or severe headaches only in the anterior zone in the adjusted model (OR and CI: anterior teeth unreplaced: 0.90(0.43, 1.88), P=.800; posterior teeth unreplaced: 1.14(1.00, 1.30), P=.047; both anterior and posterior teeth unreplaced: 1.61(1.16, 2.22), P=.007). Because of the important association between posterior missing teeth and migraine or severe headaches, further analyses found a 1 tooth increase in unreplaced posterior teeth was related to a 4% increment in migraine or severe headaches (OR and CI: 1.04(1.01, 1.07), P=.017); however, the number of replaced posterior teeth was not associated with migraine or severe headaches (OR and CI: 1.00(0.99, 1.02), P=.900)., Conclusions: The number of unreplaced missing posterior teeth was positively associated with migraine or severe headaches, while missing but restored posterior teeth were not associated with migraine or severe headaches in a US population., (Copyright © 2024 Editorial Council for The Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.)

Advancements in deep neural networks have made remarkable leap-forwards in crop detection. However, the detection of wheat ears is an important yet challenging task due to the complex background, dense targets, and overlaps between wheat ears. Currently, many detectors have made significant progress in improving detection accuracy. However, some of them are not able to make a good balance between computational cost and precision to meet the needs of deployment in real world. To address these issues, a lightweight and efficient wheat ear detector with Shuffle Polarized Self-Attention (SPSA) is proposed in this paper. Specifically, we first utilize a lightweight backbone network with asymmetric convolution for effective feature extraction. Next, SPSA attention is given to adaptively select focused positions and produce a more discriminative representation of the features. This strategy introduces polarized self-attention to spatial dimension and channel dimension and adopts Shuffle Units to combine those two types of attention mechanisms effectively. Finally, the TanhExp activation function is adopted to accelerate the inference speed and reduce the training time, and CIOU loss is used as the border regression loss function to enhance the detection ability of occlusion and overlaps between targets. Experimental results on the Global Wheat Head Detection dataset show that our method achieves superior detection performance compared with other state-of-the-art approaches., Competing Interests: Pengcheng Liu is an Academic Editor for PeerJ., (© 2022 Dong et al.)

A high-sensitivity temperature sensor based on gold-coated D-shaped photonic crystal fiber is proposed in this paper. To enhance the sensing performances, gold as the surface plasmon resonance material is coated on the polishing surface. The thermosensitive liquid consists of ethanol and chloroform, and it is placed on the outer layer of the photonic crystal fiber. As the phase-matching condition is satisfied, the core mode couples to the surface plasmon polariton mode, and energy transfer occurs. The influences of the structural parameters on the sensing characteristics were studied using the finite element method. The numerical results show the average sensitivity can reach up to 10.61 nm/°C, and the linearity R 2 =0.99341 for the temperature sensing ranges of 0-60°C. Moreover, a good spectral shape can be realized by the proposed fiber. Compared with some previously reported temperature sensors, the proposed temperature sensor shows excellent performances in terms of the sensitivity, detection range, and fabrication.

In this paper, a D-shaped photonic crystal fiber is designed to achieve a single-polarization filter that has a broadband filtering property. The D-shaped structure is a triangular array of air holes, forming a micro-opening on the side-polished surface and plating a gold layer thereon. The investigation of the polarization filter is based on the finite element method; its principle is surface plasmon resonance. The single-polarization filter in the y direction is realized by adjusting parameters such as the apertures of the fiber, the thickness of the gold layer, and the polishing depth. The confinement loss of the core mode in y polarization reaches to a high value of 376.31 dB/cm at 1.55 μm, and that of the x polarization is 0.17 dB/cm; the former is 2225.35 times the latter. When the fiber length L is 1 mm, the crosstalk reaches a peak value of 326.7 dB at 1.55 μm, and the bandwidth of crosstalk higher than 20 dB is 480 nm. In addition, the external gold coating operation is more conducive to application in the manufacturing process. This filter will be an effective application of the optical communication window near 1.55 μm.

We propose a D-shaped photonic crystal fiber (PCF) refractive index sensor with ultrahigh sensitivity and a wide detection range. The gold layer is deposited on the polished surface, avoiding filling or coating inside the air holes of the PCF. The influences of the gold layer thickness and the diameter of the larger air holes are investigated. The sensing characteristics of the proposed sensor are analyzed by the finite element method. The maximum sensitivity can reach 31,000  nm/RIU, and the refractive index detection range is from 1.32 to 1.40. Our proposed PCF has excellent sensing characteristics and is competitive in sensing devices.

Objective: To assess the significance of elevated serum N-terminal pro-brain natriuretic peptide (NT-proBNP) levels in predicting 30-day mortality rate for patients in intensive care unit (ICU)., Methods: A retrospective study was conducted. The clinical data of 480 patients admitted to ICU in Tianjin First Center Hospital from June 2012 to October 2013 were studied. The characteristics of patients were recorded, the acute physiology and chronic health evaluationII ( APACHEII) score was calculated, and the routine blood tests, blood biochemistry, and serum NT-proBNP level within 24 hours after admission were determined. Patients were divided into non-survival and survival groups according to 30-day outcome, and the characteristics and clinical parameters were compared between two groups, and single factor analysis affecting prognosis was analyzed. All patients were divided into four groups according to four percentile method as NT-proBNP<280 ng/L (group Q1), 280 ng/L≤NT-proBNP<1 200 ng/L (group Q2), 1 200 ng/L≤NT-proBNP<1 990 ng/L (group Q3), 1 990 ng/L≤NT-proBNP<4 700 ng/L (group Q4). A Cox regression analysis was used to test the independence of the predictors. A receiver operator characteristic curve (ROC curve) was plotted to compare the power of APACHEII score and NT-proBNP in predicting the outcome. Kaplan-Meier analysis was used to assess survival rate among different NT-proBNP patients., Results: By single factor analysis it was shown that age, APACHEII score, creatinine, NT-proBNP and severe infection were those influencing the outcome. NT-proBNP 1 200-4 700 ng/L (groups Q3 and Q4) and APACHEII score>20 were independent risk factors for predicting outcome [relative risk (RR) for group Q3 was 3.624, 95% credibility interval (95%CI) was 1.258-10.138; RR for group Q4 was 5.059, 95%CI was 3.202-9.993; RR for APACHEII score>20 was 2.987, 95%CI was 1.345-5.823]. The area under the ROC curve (AUC) for APACHEII score and serum NT-proBNP was similar, and it was 0.831 (95%CI 0.778-0.884) and 0.876 (95%CI 0.827-0.925), respectively. The cut-off value of NT-proBNP for predicting mortality was 1 250 ng/L. Kaplan-Meier analysis showed that groups of Q2, Q3 and Q4 had lower cumulative survival rate compared with group Q1 (26.5%, 25.4%, 16.2% vs. 29.6%), and group Q4 showed most significant extent of lowering of survival rate (χ(2)=122.920, P<0.05)., Conclusions: Elevated NT-proBNP level in ICU patients signify severity of the disease, and it is an independent predictor of death of ICU patients.