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Polyethylene terephthalate has been widely used in the packaging industry. Degraded PET micro(nano)plastics could pose public health concerns following release into various environments. This study focuses on PET degradation under ultraviolet radiation using the NIST SPHERE facility at the National Institute of Standards and Technology in saturated humidity (i.e., ≥95% relative humidity) and dry conditions (i.e., ≤5% relative humidity) with varying temperatures (30 °C, 40 °C, and 50 °C) for up 20 days. ATR-FTIR was used to characterize the chemical composition change of degraded PET as a function of UV exposure time. The results showed that the cleavage of the ester bond at peak 1713 cm−1 and the formation of the carboxylic acid at peak 1685 cm−1 were significantly influenced by UV radiation. Furthermore, the formation of carboxylic acid was considerably higher at saturated humidity and 50 °C conditions compared with dry conditions. The ester bond cleavage was also more pronounced in saturated humidity conditions. The novelty of this study is to provide insights into the chemical degradation of PET under environmental conditions, including UV radiation, humidity, and temperature. The results can be used to develop strategies to reduce the environmental impact of plastic pollution. [ABSTRACT FROM AUTHOR]

Microplastics are tangible particles of less than 0.2 inches in diameter that are ubiquitously distributed in the biosphere and accumulate in water bodies. During the east-coast hot summers (23–29 °C) of 2021 and 2022, June through September, we captured copious amounts of the jellyfish Chrysaora chesapeakei, a predominant species found in the Patuxent River of the Chesapeake Bay in Maryland on the United States East Coast. We determined that their gelatinous bodies trapped many microplastics through fluorescent microscopy studies using Rhodamine B staining and Raman Spectroscopy. The chemical nature of the microplastics was detected using gas chromatography–mass spectroscopy headspace (SPME-GC-MS) and solvent extraction (GC-MS) methods through a professional commercial materials evaluation laboratory. Numerous plastic-affiliated volatile organic compounds (VOCs) from diverse chemical origins and their functional groups (alkanes, alkenes, acids, aldehydes, ketones, ethers, esters, and alcohols) along with other non-microplastic volatile organic compounds were observed. Our findings corroborate data in the available scientific literature, distinguishing our finding's suitability. [ABSTRACT FROM AUTHOR]

This paper presents a novel parametrically controllable multi-scroll conservative chaotic system with a concise mathematical model and rich dynamic properties. The number of scrolls in the chaotic system can be regulated by a single control parameter c. Numerical simulations and theoretical analyses were performed to verify the conservative and hidden properties of the proposed system in terms of Lyapunov exponent, Equilibrium points, Kaplan–Yorke dimension. In addition, several interesting dynamical phenomena are found here, including the hidden extreme multistability, a special offset boosting and similar transient behaviors. To increase the diversity and complexity of the system, we propose a universal cascade control model with the purpose of achieving geometric control of digitized chaotic systems. The proposed scheme can flexibly and effectively control chaotic phase diagrams in 3-D space by changing the forward and reverse regulation matrices of the cascade control model. Finally, a microcontroller-based platform was built to implement the proposed 3-D system. The novel multi-scroll conservative chaotic system has rich and peculiar dynamics and is suitable for application in chaotic secure communication. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel 4D conservative chaotic system with a variety of interesting dynamic behaviors. By analyzing the divergence, Lyapunov exponent, equilibrium point and K-Y dimension of the proposed system, it is found that the system has hidden attractors and conservative characteristics. When the control parameters and initial values of the 4D conservative chaotic system are set to different values, the system shows hidden extreme multistability and offset boosting behaviors. In addition, in the case of fixed control parameters, when different initial values are selected, the system exhibits a variety of special transient transition behaviors, including quasi-periodic to periodic, quasi-periodic to hyperchaotic state. Subsequently, compared with existing systems, the complexity analysis of the chaotic sequence shows that the proposed system has a significant improvement in terms of sequence complexity. Finally, the system is implemented through a DSP hardware platform, preparing for subsequent engineering applications. [ABSTRACT FROM AUTHOR]

Background: Spontaneous fungal peritonitis (SFP) and fungiascites is less well-recognized and described in patients with liver cirrhosis. The aims of this study were to determine the clinical characteristics, prognosis, and risk factors of cirrhotic patients with SFP/fungiascites and to improve early differential diagnosis with spontaneous bacterial peritonitis (SBP). Methods: This was a retrospective case–control study of 54 cases of spontaneous peritonitis in cirrhotic patients (52 SFP and 2 fungiascites) with fungus-positive ascitic culture. Fifty-four SBP cirrhotic patients with bacteria-positive ascitic culture were randomly enrolled as a control group. A nomogram was developed for the early differential diagnosis of SFP and fungiascites. Results: Hospital-acquired infection was the main cause of SFP/fungiascites. Of the 54 SFP/fungiascites patients, 31 (57.41%) patients carried on with the antifungal treatment, which seemed to improve short-term (30-days) mortality but not long-term mortality. Septic shock and HCC were independent predictors of high 30-day mortality in SFP/fungiascites patients. We constructed a predictive nomogram model that included AKI/HRS, fever, (1,3)-β-D-glucan, and hospital-acquired infection markers for early differential diagnosis of SFP/fungiascites in cirrhotic patients with ascites from SBP, and the diagnostic performance was favorable, with an AUC of 0.930 (95% CI: 0.874–0.985). Conclusions: SFP/fungiascites was associated with high mortality. The nomogram established in this article is a useful tool for identifying SFP/fungiascites in SBP patients early. For patients with strongly suspected or confirmed SFP/fungiascites, timely antifungal therapy should be administered. [ABSTRACT FROM AUTHOR]

Playing a significant role in electrochemical energy conversion and storage systems, heteroatom-doped transition metal oxides are key materials for oxygen-involving reactions. Herein, mesoporous surface-sulfurized Fe–Co3O4 nanosheets integrated with N/S co-doped graphene (Fe–Co3O4–S/NSG) were designed as composite bifunctional electrocatalysts for the oxygen evolution reaction (OER) and the oxygen reduction reaction (ORR). Compared with the Co3O4–S/NSG catalyst, it exhibited superior activity in the alkaline electrolytes by delivering an OER overpotential of 289 mV at 10 mA cm−2 and an ORR half-wave potential of 0.77 V vs. RHE. Additionally, Fe–Co3O4–S/NSG kept stable at 4.2 mA cm−2 for 12 h without significant attenuation to render robust durability. This work not only demonstrates the satisfactory effect of the transition-metal cationic modification represented by iron doping on the electrocatalytic performance of Co3O4, but it also provides a new insight on the design of OER/ORR bifunctional electrocatalysts for efficient energy conversion. [ABSTRACT FROM AUTHOR]

Nowadays, it is increasingly necessary to improve the encryption and secure transmission performance of images. Therefore, in this paper, a bit-level permutation algorithm based on hyper chaos is proposed, with a newly constructed 5-D hyperchaotic system combined with DNA sequence encryption to achieve bit-wide permutation of plaintexts. The proposed 5-D hyperchaotic system has good chaotic dynamics, combining hyperchaotic sequence with bit-level permutation to enhance the pseudo-randomness of the plaintext image. We adopt a scheme of decomposing the plaintext color image into three matrices of R, G, and B, and performing block operations on them. The block matrix was DNA encoded, operated, and decoded. The DNA operation was also determined by the hyperchaotic sequence, and finally generated a ciphertext image. The result of the various security analyses prove that the ciphertext images generated by the algorithm have good distribution characteristics, which can not only resist differential attacks, but also have the advantages of large cryptographic space. [ABSTRACT FROM AUTHOR]

Background and aim: To develop and validate a novel machine learning-based radiomic model (RM) for diagnosing high bleeding risk esophageal varices (HREV) in patients with cirrhosis. Methods: A total of 796 qualified participants were enrolled. In training cohort, 218 cirrhotic patients with mild esophageal varices (EV) and 240 with HREV RM were included to training and internal validation groups. Additionally, 159 and 340 cirrhotic patients with mild EV and HREV RM, respectively, were used for external validation. Interesting regions of liver, spleen, and esophagus were labeled on the portal venous-phase enhanced CT images. RM was assessed by area under the receiver operating characteristic curves (AUROC), sensitivity, specificity, calibration and decision curve analysis (DCA). Results: The AUROCs for mild EV RM in training and internal validation were 0.943 and 0.732, sensitivity and specificity were 0.863, 0.773 and 0.763, 0.763, respectively. The AUROC, sensitivity, and specificity were 0.654, 0.773 and 0.632, respectively, in external validation. Interestingly, the AUROCs for HREV RM in training and internal validation were 0.983 and 0.834, sensitivity and specificity were 0.948, 0.916 and 0.977, 0.969, respectively. The related AUROC, sensitivity and specificity were 0.736, 0.690 and 0.762 in external validation. Calibration and DCA indicated RM had good performance. Compared with Baveno VI and its expanded criteria, HREV RM had a higher accuracy and net reclassification improvements that were as high as 49.0% and 32.8%. Conclusion: The present study developed a novel non-invasive RM for diagnosing HREV in cirrhotic patients with high accuracy. However, this RM still needs to be validated by a large multi-center cohort. [ABSTRACT FROM AUTHOR]

Tungsten disulfide nanosheets(WS2) and dandelion-like platinum–silver nanoparticles(PtAg NCs) were synthesized by hydrothermal method and seed-mediated growth approach, and a novel dopamine(DA) electrochemical sensor based on PtAg/WS2/GCE was developed and a new method for detecting DA was established. The investigation of scanning electron microscopy (SEM) and transmission electron microscopy(TEM) exhibited that dandelion-like PtAg NCs were successfully dispersed on the surface of WS2 nanosheets with the size about ~ 10 nm and the thickness of WS2 nanosheet could be estimated to be 3.1 ± 0.02 nm with a lattice constants of 0.6 ± 0.03 nm, X-ray diffraction(XRD) and X-ray photoelectron spectroscopy(XPS) patterns proved PtAg exists as alloy form and both were metallic phases. The electrochemical results revealed the obtained sensors possessed ideal electrocatalytic activity toward DA with a wide linear range of 0.6 μM to 1 mM(R2 = 0.9991), high sensitivity (348.8 μA·mM−1·cm−2), low detection limit 0.2 μM (S/R = 3), the relative standard deviation (RSD) was estimated to be 2.3%, current respond toward DA remains 92.79% after several day, showing a good stability, repeatability and selectivity. Moreover, compared with other similar DA sensors, the linear range of the sensor was 2 orders of magnitude wider, and the detection limit was 5 times lower. [ABSTRACT FROM AUTHOR]

Due to the influence of finite calculation accuracy and binary quantization method, the performance of chaotic binary sequences has been degraded in varying degrees, and some sequences emerge as multi-period phenomena. Aiming at the problem that it is difficult to accurately detect this phenomenon, this paper proposes a multi-period positioning algorithm (MPPA), which can accurately detect and locate the accurate period and local period phenomena contained in chaotic binary sequences. In order to test the effectiveness and correctness of the algorithm, the multi-period characteristics of logistic binary sequences with different calculation accuracy are analyzed. MPPA evaluates the randomness of binary sequences from a new perspective, which provides a new idea for the analysis of cryptographic security of chaotic sequences. [ABSTRACT FROM AUTHOR]

Early childhood development intervention has gained considerable achievements in eliminating intergenerational transmission of poverty in rural areas. Paying further attention to rural children's community inclusion can also promote the sustainable development of the village. However, there is a lack of systematic theoretical constructs on the village inclusion of rural children. In this study, an attempt was made to explore the problem mechanism and solution strategy of community inclusion of rural children using a grounded theory approach of in-depth interviews. Seventeen parents of children in a national-level poverty-stricken county in Inner Mongolia of China were investigated, adopting the strategy of intensity sampling. The results revealed that (1) the content of rural children's activities demonstrates enhanced participation in the virtual environment and weakened participation in the real community environment. That is, the activities are characterized by more virtualization and individualization. (2) Rural parents and community peers are two major channels for children's community inclusion, while both the community peer environment and parental community participation show a weakening trend. This may be an important reason for the virtualization and individualization of the children's psychological development environment. (3) Developmental intervention programs for rural children in poverty-stricken areas should focus on the reconstruction of children's community peer environment, encourage the community participation of parents, and fully mobilize local-based educational resources. [ABSTRACT FROM AUTHOR]

In this paper, we have studied the dynamic compression performance of the RSW of QP980 steel and TRIP800 steel by using a split Hopkinson pressure bar (SHPB), and we have also examined the fracture mode of the two research objects. It is found that the spot welding zone is primarily composed of the martensite structure, and there is a sparse defect of crystal structure adjacent to the center of nugget. In addition, there are evident gaps between the plates on both sides of the spot welding zone. Through the measurement of the microhardness of the two grade steel, it is found that the average hardness of the RSW of QP980 steel is higher than that of TRIP800 steel. There is a softening region in the interface of the heat affected zone and the substrate zone. The dynamic compression experiments are carried out on the RSW of QP980 steel and TRIP800 steel under 200°C and 300°C conditions, and it is found that the strain rate would increase with the rising temperature, but the compressive strength would experience declines. Furthermore, the sparse defects of crystal structure adjacent to the center of nugget would lead to stress rebound when the specimen is compressed. Moreover, through the observation of the fracture surface of the recovered specimens, it is found that the fracture of the nugget is brittle, whereas the fracture mode of the sample is more complicated. In addition, the fracture surface features a number of "river pattern" cleavage facets, and there are very few dimples of ductile tearing. This study is expected to have huge implications to the safety of vehicle body under high-speed impact. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to evaluate the potential utility of [68Ga]Ga-FAPI-04 PET/CT for diagnosing primary and metastatic lesions in patients with liver cancer, as well as to compare it with contrast-enhanced CT (CE-CT), liver MRI, and [18F]-FDG PET/CT. Methods: We performed a single-center post hoc retrospective analysis of data obtained from a prospective parent study (NCT04416165). This study included 34 patients diagnosed with or suspected hepatic lesions who underwent concomitant [68Ga]Ga-FAPI-04 and [18F]-FDG/CT scans. Moreover, these patients underwent liver MRI (n = 34) and CE-CT (n = 25). Histopathologic (n = 62) or radiographic follow-up (n = 128) served as the reference standard for the final diagnosis. Results: Among the 34 patients, 20, 12, and 2 patients presented with hepatocellular carcinomas, intrahepatic cholangiocarcinomas, and benign hepatic nodules, respectively. The sensitivities of CE-CT, MRI, [68Ga]Ga-FAPI-04, and [18F]-FDG/CT for detecting primary liver tumors were 96%, 100%, 96%, and 65%, respectively. Regarding the diagnosis of all intrahepatic lesions, the per-lesion detection rate of [68Ga]Ga-FAPI-04 PET/CT was slightly lower than that of MRI (85% vs. 100%, P = 0.34) and significantly higher than that of [18F]-FDG PET/CT (85% vs. 52%, P < 0.001). Regarding the diagnosis of all malignant lesions (including extrahepatic disease), the tumor detection rate of [68Ga]Ga-FAPI-04 PET/CT was 87.4%, which was significantly higher than that of [18F]-FDG PET/CT (65.0%, P < 0.001). Conclusions: Our findings indicate that the sensitivity of [68Ga]Ga-FAPI-04 PET/CT to correctly identify primary liver tumors and metastatic lesions is equivalent to that of CE-CT and liver MRI. Moreover, [68Ga]Ga-FAPI-04 PET/CT is better at identifying liver lesions than [18F]-FDG PET/CT, and its use may improve tumor staging, recurrence detection, and implementation of necessary treatment modifications. [ABSTRACT FROM AUTHOR]

Purpose: This prospective study aimed to evaluate the potential usefulness of [68Ga]Ga-DOTA-FAPI-04 positron emission tomography/computed tomography (PET/CT) in the oncological evaluation of patients presenting with inconclusive [18F]FDG PET/CT findings. Methods: [68Ga]Ga-DOTA-FAPI-04 was performed in patients presenting with inconclusive [18F]FDG PET/CT findings. Tumour uptake was quantified by the maximum standard uptake value (SUV). Histopathology or follow-up imaging served as the standard for the final diagnosis. Results: A total of 68 patients with inconclusive [18F]FDG PET/CT findings underwent additional [68Ga]Ga-DOTA-FAPI-04 PET/CT. Of them, 18 (26.5%) were for discrimination of mass lesions detected on conventional imaging, 6 (8.8%) for detection of the unknown primary site in biopsy-proven metastatic malignancy, 21 (30.9%) for the staging of cancer, and the other 23 (33.8%) for evaluation of suspected disease recurrence. Most of the primary and metastatic lesions demonstrated higher uptake of [68Ga]Ga-DOTA-FAPI-04 than did [18F]FDG, which resulted in favourable tumour-to-background contrast in various types of cancer. As a result, [68Ga]Ga-DOTA-FAPI-04 PET/CT identified suspicious mass lesions with an accuracy of 12/18 (66.7%), detected the primary site in 4/6 patients (66.7%) with unknown malignancy, upgraded tumour staging in 7/21 patients (33.3%), and detected disease recurrence in 20/23 patients (87.0%). Conclusions: In patients undergoing oncological evaluation with inconclusive [18F]FDG PET/CT findings, [68Ga]Ga-DOTA-FAPI-04 may have a complementary role in discriminating mass lesions on conventional imaging, locating the primary site of unknown malignancy, modifying tumour staging, and detecting suspected disease recurrence. Nevertheless, careful attention should be paid when reading the [68Ga]Ga-DOTA-FAPI-04 PET/CT images in tumours complicated with inflammation. [ABSTRACT FROM AUTHOR]

To analyze the effects of finite computational precision on the dynamical degradation of digital chaotic maps, we designed a periodic orbit detection algorithm that is based on a functional graph. The algorithm can calculate the transient length of each chaotic orbit, weak secret keys, fixed points and the period distribution of digital chaotic systems with various limited computational precisions accurately. Furthermore, an effective method based on quadratic congruential generator is proposed to counteract the performance degradation of digital chaos. Based on the method, a new chaotic model can be constructed with full cycle. Numerical experiments are carried out to evaluate the feasibility of the proposed scheme in terms of phase portrait, autocorrelation function, complexity and periodicity analysis. Finally, as an application, a pseudorandom bit generator with satisfactory performance is designed for chaotic secure communication. [ABSTRACT FROM AUTHOR]

Adaptive feeding is a strategy used by many organisms to maintain growth and reproduction success while encountering varying feeding conditions. Oysters are sessile benthic and non‐siphon filter feeders. Oysters are well adapted to modify the ambient microenvironment through their pumping behavior and particle selection activity. Rejection of unsuitable food particulates bound in pseudofeces via ejection events are an integral part of oyster feeding during which oysters produced strong flow opposite to their inhalant feeding flow. The strong opposite pulsatile flow during the ejection event inevitably disrupts the oyster's normal feeding cycle, but how oysters restart their feeding and allocate their energy consumption during an ejection event has not been investigated. The present study used particle image velocimetry (PIV) to examine the impact of ejection events on the feeding of the American oyster, Crassostrea virginica. The strong pulsatile flow resulting from pseudofecal ejection altered the external flow fields by moving water away from the shell. The initial feeding zone after pseudofecal ejection was relatively narrow, possessed a low pulsatile flow, and did not exploit the full flow field. The feeding zone gradually expanded as the pulsatile flow weakened. The strong shear rate at the stable feeding zone then sustained the feeding flow that facilitated oyster feeding. Furthermore, the volumetric fluxes often increased after the ejection event, suggesting increase in feeding efficiency after ejection events. These PIV studies provide new insight on the interactions between feeding oysters and the surrounding physical environment at small yet ecologically relevant scales. [ABSTRACT FROM AUTHOR]

Untangling organisms' multi‐scale spatial distributions is challenging due to their interactions with environments at multiple spatial and temporal scales. We deployed an Adaptive Resolution Imaging Sonar (ARIS) in a Chesapeake Bay sub‐estuary to investigate multi‐scale spatial distributions of the bay nettle (Chrysaora chesapeakei) in May–September of 2016 and 2017. Nettles were found to be dispersed in aggregations of multiple individuals. The average density of bay nettles in 2017 was higher than in 2016. Small aggregations (<5 m) were persistent in both years but only contributed <10% of total observed nettles. Large patches (>30 m) contributed ~40% of the total observed nettles. Large patches were more common in creek habitat where nettle density was higher. Nettle density was found to hit a peak value once in 2016, while there were two density peaks in 2017. Different aggregation patterns were observed during the second peak period in 2017 in which the number of large patches increased dramatically. Within the surveyed waterscape, the spatial patterns were consistent over time with higher abundance in the source creek than in the river channel, which underscores that C. chesapeakei requires hard substrate in shallow creeks for its benthic polyp stage. Using the ratio between nettles in the creek and near creek mouth as a proxy for dispersal rate, more nettles were transported out of the creek in 2017 than in 2016. The increase in patch size and high dispersion rate in peak periods in 2017 suggests that individuals were moving out of the creek habitat as density increased. Results highlight the complex spatial structure of bay nettles, which has major impacts on density estimates and subsequently affects our understanding of jellyfish population dynamics and long‐term trends. [ABSTRACT FROM AUTHOR]

The Subei Shoal is a special coastal area with complex physical oceanographic properties in the Yellow Sea. In the present study, the distribution of phytoplankton and its correlation with environmental factors were studied during spring and summer of 2012 in the Subei Shoal of the Yellow Sea. Phytoplankton species composition and abundance data were accomplished by Utermöhl method. Diatoms represented the greatest cellular abundance during the study period. In spring, the phytoplankton cell abundance ranged from 1.59×103 to 269.78×103 cell/L with an average of 41.80×103 cell/L, and Skeletonema sp. and Paralia sulcata was the most dominant species. In summer, the average phytoplankton cell abundance was 72.59×103 cell/L with the range of 1.78×103 to 574.96×103 cell/L, and the main dominant species was Pseudo-nitzschia pungens, Skeletonema sp., Dactyliosolen fragilissima and Chaetoceros curvisetus. The results of a redundancy analysis (RDA) showed that turbidity, temperature, salinity, pH, dissolved oxygen (DO), the ratio of dissolved inorganic nitrogen to silicate and SiO4-Si (DIN/SiO4-Si) were the most important environmental factors controlling phytoplankton assemblages in spring or summer in the Subei Shoal of the Yellow Sea. [ABSTRACT FROM AUTHOR]

The dynamics of chaotic maps are severely inhibited by the limited precision of the computational device that is used to implement them, and thus, their applications in cryptography and secure communications are seriously limited. To evaluate the degree of degradation of digital chaotic maps, we designed a fast period search algorithm (FPSA) that is based on a tree structure for analysing the periodicities of digital chaotic maps from a new perspective. FPSA can calculate the maximal transient length, fixed points and periodic limit cycles of digital chaotic maps in finite-precision domains quickly and accurately. Furthermore, based on this algorithm, the security of 1-D logistic maps and 2-D Arnold maps in engineering applications is analysed to demonstrate the versatility and effectiveness of our proposed algorithm. This algorithm plays an active role in analysing the structures of the functional graphs of digital chaotic maps in digital computers. [ABSTRACT FROM AUTHOR]

The performance of digital chaotic systems in secure communications and cryptographic applications is significantly degraded due to the limited precision of digital computational devices that are used to implement digital chaotic systems. However, regardless of the initial value, the digital chaotic map employed in these applications converges to several periodic orbits. Thus, a periodic orbit search algorithm (POSA) can be designed to accurately locate fixed points and limit cycles. In addition, an effective method based on stochastic jumps of chaotic orbits is proposed to counteract the performance degradation of digital chaos. Numerical simulations were performed to assess the effectiveness and feasibility of the proposed method in terms of autocorrelation, phase space inspection, approximate entropy and periodicity analysis. Furthermore, comparison with other existing methods is presented to show the competitiveness of the proposed scheme. Finally, a pseudorandom bit generator (PRBG), with desirable statistical properties, is constructed for chaos cryptography and other applications. [ABSTRACT FROM AUTHOR]

At present, the performance of the digital chaotic sequence generator is affected by the calculation precision of processor and quantization method, which leads to the quantized chaotic binary sequences emerging from some periodic phenomena in the local range of sequences. However, in view of the current methods for analyzing the periodicity and randomness of binary sequences, evaluating the periodic characteristics which exist in the local range of chaotic binary sequences is extremely difficult. Therefore, in this paper, we have proposed a novel algorithm called the GBSPD (General Binary Sequences Periodic Detection) algorithm, which can detect typical periodic phenomena and local periodic phenomena in the chaotic binary sequence. Moreover, it can accurately locate the position of periodic phenomena of binary sequences and perform a detailed statistical analysis. Furthermore, by using the GBSPD algorithm to detect the periodic characteristics of the quantified logistic chaotic binary sequences, the experimental results show that the algorithm can effectively locate multiple periodic phenomena in the binary sequences. [ABSTRACT FROM AUTHOR]

At present, the performance of the digital chaotic sequence generator is affected by the calculation precision of processor and quantization method, which leads to the quantized chaotic binary sequences emerging from some periodic phenomena in the local range of sequences. However, in view of the current methods for analyzing the periodicity and randomness of binary sequences, evaluating the periodic characteristics which exist in the local range of chaotic binary sequences is extremely difficult. Therefore, in this paper, we have proposed a novel algorithm called the GBSPD (General Binary Sequences Periodic Detection) algorithm, which can detect typical periodic phenomena and local periodic phenomena in the chaotic binary sequence. Moreover, it can accurately locate the position of periodic phenomena of binary sequences and perform a detailed statistical analysis. Furthermore, by using the GBSPD algorithm to detect the periodic characteristics of the quantified logistic chaotic binary sequences, the experimental results show that the algorithm can effectively locate multiple periodic phenomena in the binary sequences. [ABSTRACT FROM AUTHOR]

In this paper, we analyzed the periodicity of discrete Logistic and Tent sequences with different computational precision in detail. Further, we found that the process of iterations of the Logistic and Tent mapping is composed of transient and periodic stages. Surprisingly, for the different initial iterative values, we first discovered that all periodic stages have the same periodic limit cycles. This phenomenon has seriously affected the security of chaotic cipher. To solve this problem, we designed a novel discrete chaotic sequence generator based on m-sequence and discrete chaotic mapping. The experimental results indicated that the chaotic sequence generator can generate pseudorandom chaotic sequences with large periodicity and good performance under the condition of limited computational precision. [ABSTRACT FROM AUTHOR]

The chaotic behavior of low-dimensional digital chaotic systems is seriously degraded, and the output sequence has a short period. In this study, a digital sequence generator based on a high-dimensional chaotic system is proposed to ensure performance and security. The proposed generator has low resource consumption, and the digital pseudo-random output sequence has a large period. To avoid the nonchaotic state, the multistability in the high-dimensional discrete chaotic system is analyzed. The statistical performance of the output sequence of the proposed digital high-dimensional chaotic system is evaluated, and the results demonstrate that it is a suitable candidate for a long-period pseudo-random sequence generator. [ABSTRACT FROM AUTHOR]

The chaotic system is widely used in chaotic cryptosystem and chaotic secure communication. In this paper, a universal method for designing the discrete chaotic system with any desired number of positive Lyapunov exponents is proposed to meet the needs of hyperchaotic systems in chaotic cryptosystem and chaotic secure communication, and three examples of eight-dimensional discrete system with chaotic attractors, eight-dimensional discrete system with fixed point attractors and eight-dimensional discrete system with periodic attractors are given to illustrate how the proposed methods control the Lyapunov exponents. Compared to the previous methods, the positive Lyapunov exponents are used to reconstruct a hyperchaotic system. [ABSTRACT FROM AUTHOR]

The informed dynamic scheduling (IDS) strategy decoding algorithms performed exceptionally well for low-density parity-check codes in terms of the error-rate performance. However, the IDS decoding algorithm is greedy because of the unfair computation resources allocation among different variables nodes, which leads to poor convergence performance. In order to reduce the greediness of the IDS algorithm, the tabu search (TS) algorithm is introduced to the dynamic scheduling-based decoding in this paper. In the TS-based dynamic scheduling (TSDS) algorithm, the variable nodes in the Tanner graph are temporarily stored in a tabu list. In the decoding process with the TSDS algorithm, variable nodes stored in the tabu list will not be selected and updated until they are shifted out of the tabu list. Besides, an improved updating order is provided for the TSDS algorithm, by which the computational complexity can be decreased without the loss of error correction performance. Simulation results show that the proposed algorithm outperforms other decoding algorithms of interest in terms of bit error rate and convergence performance over the additive white Gaussian noise channel. [ABSTRACT FROM AUTHOR]

Although the association of Internet addiction (IA) with self-regulation has been widely observed in previous studies, its variance with age remains poorly understood. Using dual models of self-regulation, we aimed to test the effects of effortful control and impulsivity on IA and to explore the effect of the interaction between age stage and self-regulation on IA. In this study, 4313 students nested in 100 classes were surveyed using the Internet Addiction Test (IAT), the Dual-Modes of Self-Control Scale (DMSC-S) and a demographic questionnaire. Hierarchical generalized linear models (HGLMs) were then used to test our assumptions. The results indicated that the IA prevalence rate among the surveyed adolescents was 10.9%, and IA was found to be negatively related to the effortful control trait and positively related to the impulsivity trait. Compared with primary school students, middle school students were more likely to be Internet addicts; however, the prevalence of IA among college students was comparable to that among middle school students. A slopes-as-outcome model showed that the association between IA and effort control was stronger among junior high school students than among students in other grade levels, but no grade differences were found in the slopes for impulsivity. We integrate our results with the findings of previous studies and discuss possible theoretical implications. [ABSTRACT FROM PUBLISHER]

A ratiometric fluorescent probe 2-(benzimidazol-2-yl)phenyl phosphoric acid (1) for alkaline phosphatase (ALP) is designed and synthesized. The method employs the modulation of the excited-state intramolecular proton transfer (ESIPT) process of 2-(2'-hydroxyphenyl)benzimidazole (HPBI) through the hydroxyl group protection/deprotection reaction. Upon phosphorylated with POCl3, HPBI shows only an emission peak at 363 nm due to the blockage of ESIPT. However, once selective enzymatic hydrolysis with alkaline phosphatase (ALP) in Tris-HCl buffer occurs, the probe 1 is returned to HPBI and the ESIPT process is switched on, which results in a decrease in the emission band at 363 nm and an increase in a new fluorescence peak around 430 nm. The fluorescence intensity ratio at 430 and 360 nm (I430/I360) increases linearly with the activity of ALP up to 0.050 U/mL and the detection limit is 0.0013 U/mL. The proposed probe shows excellent specificity toward ALP. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Although ego depletion effects have been widely observed in experiments in which participants perform consecutive self-control tasks, the process of ego depletion remains poorly understood. Using the strength model of self-control, we hypothesized that chronic ego depletion adversely affects goal adherence and that mental effort and motivation are involved in the process of ego depletion. In this study, 203 students reported their daily performance, mental effort, and motivation with respect to goal directed behavior across a 3-week time period. People with high levels of chronic ego depletion were less successful in goal adherence than those with less chronic ego depletion. Although daily effort devoted to goal adherence increased with chronic ego depletion, motivation to adhere to goals was not affected. Participants with high levels of chronic ego depletion showed a stronger positive association between mental effort and performance, but chronic ego depletion did not play a regulatory role in the effect of motivation on performance. Chronic ego depletion increased the likelihood of behavior regulation failure, suggesting that it is difficult for people in an ego-depletion state to adhere to goals. We integrate our results with the findings of previous studies and discuss possible theoretical implications. [ABSTRACT FROM AUTHOR]

The Internet has been building a new context, in which adolescents and young people complete their academic tasks, do their work, engage in social interaction, and even conduct anonymous identity experimentation. Therefore, it becomes very significant to assess psychological need satisfaction online, and to relate it to well-being. This study investigated the influence on well-being of psychological need satisfaction perceived online and the regulatory role in this relationship of psychological need satisfaction perceived in daily life. A total of 1,727 students from junior and senior high schools and universities in China were surveyed using the Basic Psychological Needs in General scale, the Basic Psychological Needs in the Online World scale, and the Index of Well- Being, Index of General Affect scale. The mean age of the adolescent sample was 17.47 years (ranging from 12.50 to 25.42 years). The results indicated that both need satisfaction perceived online and that perceived in daily life positively predicted psychological well-being, and psychological need satisfaction in daily life qualified the association between psychological need satisfaction perceived online and well-being. In particular, students who perceived higher psychological need satisfaction in daily life were found to benefit from psychological need satisfaction perceived online, but students with low psychological need satisfaction perceived in daily life did not. We suggest that people who perceive lower basic need satisfaction in daily life are more likely to use the Internet for socioaffective regulation and to consider cyberspace as a new world. Thus, need satisfaction perceived online may not transform into 'real' happiness. [ABSTRACT FROM AUTHOR]

Plankton imaging systems are capable of providing fine-scale observations that enhance our understanding of key physical and biological processes. However, processing the large volumes of data collected by imaging systems remains a major obstacle for their employment, and existing approaches are designed either for images acquired under laboratory controlled conditions or within clear waters. In the present study, we developed a semi-automated approach to analyze plankton taxa from images acquired by the ZOOplankton VISualization (ZOOVIS) system within turbid estuarine waters, in Chesapeake Bay. When compared to images under laboratory controlled conditions or clear waters, images from highly turbid waters are often of relatively low quality and more variable, due to the large amount of objects and nonlinear illumination within each image. We first customized a segmentation procedure to locate objects within each image and extracted them for classification. A maximally stable extremal regions algorithm was applied to segment large gelatinous zooplankton and an adaptive threshold approach was developed to segment small organisms, such as copepods. Unlike the existing approaches for images acquired from laboratory, controlled conditions or clear waters, the target objects are often the majority class, and the classification can be treated as a multi-class classification problem. We customized a two-level hierarchical classification procedure using support vector machines to classify the target objects (< 5%), and remove the non-target objects (> 95%). First, histograms of oriented gradients feature descriptors were constructed for the segmented objects. In the first step all non-target and target objects were classified into different groups: arrow-like, copepod-like, and gelatinous zooplankton. Each object was passed to a group-specific classifier to remove most non-target objects. After the object was classified, an expert or non-expert then manually removed the non-target objects that could not be removed by the procedure. The procedure was tested on 89,419 images collected in Chesapeake Bay, and results were consistent with visual counts with >80% accuracy for all three groups. [ABSTRACT FROM AUTHOR]

Corpora cavernosum smooth muscle cells (CCSMCs) have been shown to play a critical role in the male erectile response and are involved in the pathogenesis of multiple causes of erectile dysfunction (ED). To investigate the underlying mechanisms, we studied the changes that CCSMCs undergo under hypoxic conditions in vitro. The identified and characterized CCSMCs were exposed to hypoxia for 48 h and its phenotypic changes were examined by light and electron microscopy, MTS assay and flow cytometry. The mRNA and protein levels of TGF-β1 and type I/III collagen, as well as CCSMC phenotype marker proteins and their transcriptional factors, were assessed by qPCR, immunofluorescence analysis and western blotting. Our results showed that CCSMCs became hypertrophic with loss of myofilament bundles and formation of an extensive rough endoplasmic reticulum (RER) under hypoxic conditions, with inhibited cell proliferation and enhanced cell apoptosis. This was accompanied by the increased synthesis of TGF-β1 and types I and III collagen. Moreover, smooth muscle cell phenotypic markers were also affected by hypoxic conditions, as indicated by the decrease in α-SMA, desmin and CNN1 expression and the increase in vimentin expression. These changes corresponded to changes in associated transcriptional factors, such as the increase in Elk-1 and KLF-4 expression and decrease in Myocd expression. In addition, a HIF-1α knockdown effectively reversed the hypoxia-induced CCSMC phenotype, whereas its overexpression induced the dedifferentiation phenotype. These results indicate that CCSMCs undergo a phenotypic transition under hypoxic conditions. [ABSTRACT FROM AUTHOR]

Experiments of dense-phase pneumatic conveying of pulverized coal using nitrogen were performed in an experimental test facility with the conveying pressure up to 4MPa and the solid-gas ratio up to 500 kg/m3. The influences of the total conveying differential pressure, the moisture content, the superficial velocity and the pressure on the mass flow rate and the solid-gas ratio were investigated. Shannon entropy analysis of pressure fluctuation time series was developed to reveal the flow characteristics. Based on the distribution of the Shannon entropy in the different conditions, the flow stability and the evolutional tendency of Shannon entropy in different regimes and the regime transition processes were obtained. The results indicate that the solid gas ratio and Shannon entropy rise with increase in the total conveying differential pressure. A phase diagram and Shannon entropy reveal preferable regularity with superficial velocity. Shannon entropy is different for the different flow regimes, and it can be used to identify the flow regimes. As the moisture content increases, the mass flow rate, the pressure drop and Shannon entropy decrease. Shannon entropy rises with increase in pressure drop. [ABSTRACT FROM AUTHOR]

Experiments of dense-phase pneumatic conveying of pulverized coal were carried out in a test facility with a conveying pressure up to 4 MPa. The influence of fluidization nitrogen flow rate, the flow rate of supplementary nitrogen, and the pressure difference between sending hopper and receiving hopper on the solids to gas ratio and the solid mass flow rate was investigated. Test results indicate that with the increase in fluidization nitrogen flow rate, the solid mass flow rate increases, and the solids to gas ratio increases at first and then declines. When the fluidization of pulverized coal in the sending vessel becomes intensive, with the increase in supplementary nitrogen flow rate, the solids to gas ratio declines and the solid mass flow rate increases. And the solid mass flow rate increases linearly with the increase in pressure difference between two hoppers. The experimental results provide a database for the design and operation of a dense-phase pneumatic conveying system. [ABSTRACT FROM AUTHOR]

Phenolic resin/carbon fiber (PF/CF) composites have good tribological properties; however, their extensive applications are limited because of the poor thermal conductivity of the phenolic resins. In this work, core‑shell particles of polyaniline‐coated (3‐aminopropyl) triethoxysilane‐modified β‐Si3N4 (m‐SiN@PANI) were used to enhance the tribological, electrical, and thermal conductivity properties of a PF/CF composite. A core‑shell particle, consisting of m‐SiN@PANI, was characterized by Fourier Transform Infrared Spectrometry, X‐Ray Diffraction, Scanning Electron Microscope, and Transmission Electron Microscope. The friction, thermal, and electrical properties of the composites were characterized by multifunctional vertical friction testing, wear measurement testing, thermogravimetric analysis, thermal constant analysis, and electrical conductivity testing. Remarkably, the test results showed that compared with the wear surface of the PF/CF composite, that of the phenolic resin/(2.0 wt % m‐SiN@PANI)/carbon fiber composite exhibited a smoother morphology. The results indicated that the addition of m‐SiN@PANI effectively improved the thermal conductivity, electrical conductivity, friction coefficient, and wear rate of the composites, which were 3.164 Wm−1 K−1, 5.33 × 10−6 S/m, 0.1681 and 1.13 × 10−8 mm3/Nm, respectively. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47785. [ABSTRACT FROM AUTHOR]

Background: In this systematic review and meta-analysis, we aimed to determine the risk factors associated with neck hematoma requiring surgical re-intervention after thyroidectomy.Methods: We systematically searched all articles available in the literature published in PubMed and CNKI databases through May 30, 2017. The quality of these articles was assessed using the Newcastle-Ottawa Quality Assessment Scale, and data were extracted for classification and analysis by focusing on articles related with neck hematoma requiring surgical re-intervention after thyroidectomy. Our meta-analysis was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analyses guidelines.Results: Of the 1028 screened articles, 26 met the inclusion criteria and were finally analyzed. The factors associated with a high risk of neck hematoma requiring surgical re-intervention after thyroidectomy included male gender (odds ratio [OR]: 1.86, 95% confidence interval [CI]: 1.60-2.17, P < 0.00001), age (MD: 4.92, 95% CI: 4.28-5.56, P < 0.00001), Graves disease (OR: 1.81, 95% CI: 1.60-2.05, P < 0.00001), hypertension (OR: 2.27, 95% CI: 1.43-3.60, P = 0.0005), antithrombotic drug use (OR: 1.92, 95% CI: 1.51-2.44, P < 0.00001), thyroid procedure in low-volume hospitals (OR: 1.32, 95% CI: 1.12-1.57, P = 0.001), prior thyroid surgery (OR: 1.93, 95% CI: 1.11-3.37, P = 0.02), bilateral thyroidectomy (OR: 1.19, 95% CI: 1.09-1.30, P < 0.0001), and neck dissection (OR: 1.55, 95% CI: 1.23-1.94, P = 0.0002). Smoking status (OR: 1.19, 95% CI: 0.99-1.42, P = 0.06), malignant tumors (OR: 1.00, 95% CI: 0.83-1.20, P = 0.97), and drainage used (OR: 2.02, 95% CI: 0.69-5.89, P = 0.20) were not significantly associated with postoperative neck hematoma.Conclusion: We identified certain risk factors for neck hematoma requiring surgical re-intervention after thyroidectomy, including male gender, age, Graves disease, hypertension, antithrombotic agent use, history of thyroid procedures in low-volume hospitals, previous thyroid surgery, bilateral thyroidectomy, and neck dissection. Appropriate intervention measures based on these risk factors may reduce the incidence of postoperative hematoma and yield greater benefits for the patients. [ABSTRACT FROM AUTHOR]

Maryland Coastal Bays (MCBs) have undergone changes in water quality in the past two decades due to nutrient enrichment but the composition and dynamics of the phytoplankton community have not been adequately described. Microscopic counts and photosynthetic pigments of samples collected monthly in 2012 at selected sites in MCBs that differed with regard to the degree of anthropogenic impacts were examined. Sixty-three (63) phytoplankton genera were recorded, of which 40 species are being reported for the first time in the Bays. Among the dominant species were Dactyliosolen fragilissimus (Bacillariophyta), Paulinella ovalis (Cercozoa) and Cryptomonas sp. (Cryptophyta). Bloom densities of Heterocapsa rotundata (Miozoa), which previously had not been reported in the Bays, were observed bay-wide in December, particularly at the mouth of St. Martin River. Diatoms dominated (>40%) the phytoplankton community in winter and decreased in spring (<40%), while Cercozoa and microphytoflagellates (MPF) co-dominated in summer (July). From August to October, diatoms dominated with maximum contributions from an unidentified small (<10 µM) centric species and co-dominated the assemblage with cryptophytes in late fall (November). Canonical correspondence analysis indicated that diatoms were favored by high salinity and total dissolved phosphorus (TDP), cercozoans and chlorophytes by total dissolved nitrogen (TDN) and cryptophytes by dissolved organic carbon. The spatial and seasonal differences in the composition of phytoplankton species, coupled with the occurrence of potentially toxic species and bloom densities of H. rotundata suggest that important changes have occurred in the phytoplankton assemblage that likely have affected the food web of these eutrophic bays. [ABSTRACT FROM AUTHOR]

In this paper, a novel image encryption scheme is proposed for the secure transmission of image data. A self-synchronous chaotic stream cipher is designed with the purpose of resisting active attack and ensures the limited error propagation of image data. Two-dimensional discrete wavelet transform and Arnold mapping are used to scramble the pixel value of the original image. A four-dimensional hyperchaotic system with four positive Lyapunov exponents serve as the chaotic sequence generator of the self-synchronous stream cipher in order to enhance the security and complexity of the image encryption system. Finally, the simulation experiment results show that this image encryption scheme is both reliable and secure. [ABSTRACT FROM AUTHOR]