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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]

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]

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]

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]