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Background: The ongoing coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) and the Omicron variant presents a formidable challenge for control and prevention worldwide, especially for low- and middle-income countries (LMICs). Hence, taking Kazakhstan and Pakistan as examples, this study aims to explore COVID-19 transmission with the Omicron variant at different contact, quarantine and test rates. Methods: A disease dynamic model was applied, the population was segmented, and three time stages for Omicron transmission were established: the initial outbreak, a period of stabilization, and a second outbreak. The impact of population contact, quarantine and testing on the disease are analyzed in five scenarios to analysis their impacts on the disease. Four statistical metrics are employed to quantify the model's performance, including the correlation coefficient (CC), normalized absolute error, normalized root mean square error and distance between indices of simulation and observation (DISO). Results: Our model has high performance in simulating COVID-19 transmission in Kazakhstan and Pakistan with high CC values greater than 0.9 and DISO values less than 0.5. Compared with the present measures (baseline), decreasing (increasing) the contact rates or increasing (decreasing) the quarantined rates can reduce (increase) the peak values of daily new cases and forward (delay) the peak value times (decreasing 842 and forward 2 days for Kazakhstan). The impact of the test rates on the disease are weak. When the start time of stage II is 6 days, the daily new cases are more than 8 and 5 times the rate for Kazakhstan and Pakistan, respectively (29,573 vs. 3259; 7398 vs. 1108). The impact of the start times of stage III on the disease are contradictory to those of stage II. Conclusions: For the two LMICs, Kazakhstan and Pakistan, stronger control and prevention measures can be more effective in combating COVID-19. Therefore, to reduce Omicron transmission, strict management of population movement should be employed. Moreover, the timely application of these strategies also plays a key role in disease control. [ABSTRACT FROM AUTHOR]

To overcome limitations with respect to the low sensitivity of rapid immunoassay methods due to dilution of the extract in extraction solution, ultra-sensitive antibodies are needed. The linker-tethering site between the target and carrier protein, the length of the spacer arm, and the atomic charge of the linker-tethering site between the target and spacer arm in haptens design play a pivotal role in the preparation of ultra-sensitive antibodies. In this study, carbendazim (CBZ), a systemic broad-spectrum fungicidal pesticide, was used as model compound. 2-Aminobenzimidazole was chosen as the common skeletal structure and reacted with different groups, such as alkanes and urine groups, to form haptens H1 (previously reported), H2 (novel), and H3 (novel), respectively. Subsequently, eight monoclonal antibodies (mAbs) were generated using these three haptens, which exhibited notable variation in sensitivity. The half maximal inhibitory concentration (IC 50) value of mAb 4B11 based on hapten H3 against CBZ was 0.04 ng/mL, which was seven times better than that of mAb 5B10 (IC 50 value of 0.28 ng/mL) prepared using hapten H2 and 129 times better than that of mAb 6D5 (IC 50 value of 5.15 ng/mL) prepared using hapten H1. Finally, the optimal antigen–antibody combination was employed to establish a sensitive colloidal gold lateral flow immunoassay (CG-LFA) for CBZ detection in vegetables and fruits with convenient sample pretreatment. The developed CG-LFA shows promising practical utility and prospects for application due to its low limit of detection (0.10–0.18 ng/mL) and high recovery ratios (76.0%–96.1%) in six different samples. [Display omitted] • A novel hapten design strategy focuses on the link site and spacer arm length of the target compound. • An ultra-sensitive monoclonal antibody (mAb) 4B11 against carbendazim was prepared. • A sensitive colloidal gold lateral flow immunoassay in fruits and vegetables was developed. [ABSTRACT FROM AUTHOR]

• Mesoporous materials with different pore sizes of 16.9 nm and 23.1 nm were prepared respectively. • The smaller pore size increases the pseudo-capacitance and decreases the R ct. • Pore size optimization facilitates material charge/discharge capacity and rate performance. The mesopore structure is critical to the performance of anode for LIBs, while the effect of pore size on the electrochemical properties of the materials remains unclear. In this study, mesoporous MnO 2 /acetylene black composites with different pore sizes exhibit similar reaction mechanisms but significantly differ in rate performance. This difference may be primarily attributed to the local electrochemical environment of the electrode. This study provides a new perspective for enhancing the rate capability of manganese-based oxides from the microstructure tuning. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two materials that are not electrochemically active towards lithium ions are compounded and the resulting Fe/Li 2 O composite has excellent rate performance. • The Fe/Li 2 O composites consisting of two non-electrochemically active materials have excellent rate performance. • Composite materials with a large number of heterogeneous interfaces are obtained after the compounding of Fe and Li 2 O by a facile balling method. • Composite materials with a large number of heterogeneous interfaces are obtained after a facile balling method. • The storage of lithium ions is controlled by a combination of capacitance and diffusion, in which the interface capacitance process dominates. • The kinetic properties of lithium-ion storage are mainly controlled by interfacial capacitance processes. Based on the "job-sharing" mechanism, we have designed novel anode materials for LIBs, consisting of nano-transition metal and lithium oxide particles. The composites exhibit excellent rate performance, maintaining a specific capacity of 29% of the stabilized capacity at 6 A g−1. Since neither metallic iron nor lithium oxide has lithium storage capacity, the lithium storage behavior of the composites is mainly related to the interface. Moreover, the interface facilitates the improvement of the ion diffusion ability and pseudocapacitance percentage of the composite material. This study provides new horizons for designing anode materials for high power density LIBs. [ABSTRACT FROM AUTHOR]

Human calcium sensing receptor (CaSR) senses calcium ion concentrations in vivo and is an important class of drug targets. Mutations in the receptor can lead to disorders of calcium homeostasis, including hypercalcemia and hypocalcemia. Here, 127 CaSR-targeted nanobodies were generated from camels, and four nanobodies with inhibitory function were further identified. Among these nanobodies, NB32 can effectively inhibit the mobilization of intracellular calcium ions (Ca2+ i) and suppress the G 12/13 and ERK 1/2 signaling pathways downstream of CaSR. Moreover, it enhanced the inhibitory effect of the calcilytics as a negative allosteric modulator (NAM). We determined the structure of complex and found NB32 bound to LB2 (Ligand-binding 2) domain of CaSR to prevent the interaction of LB2 domains of two protomers to stabilize the inactive state of CaSR. • 127 CaSR-targeting nanobodies were screened from camels. • NB32 effectively inhibit the mobilization of intracellular calcium ions. • NB32 enhanced the inhibitory effect of the calcilytics as a negative allosteric modulator (NAM). • Cryo-EM revealed that NB32 binds to the LB2 domain of CaSR. [ABSTRACT FROM AUTHOR]

In this paper, we study the complex dynamical behaviors of a discrete-time SIR epidemic model. Analysis of the model demonstrates that the Diseases Free Equilibrium (DFE) point is globally asymptotically stable if the basic reproduction number is less than one while the Endemic Equilibrium (EE) point is globally asymptotically stable if the basic reproduction number is greater than one. The results are further substantiated visually with numerical simulations. Furthermore, numerical results demonstrate that the discrete model has more complex dynamical behaviors including multiple periodic orbits, quasi-periodic orbits and chaotic behaviors. The maximum Lyapunov exponent and chaotic attractors also confirm the chaotic dynamical behaviors of the model. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the global dynamics of a general susceptible-infected-recovered-susceptible (SIRS) epidemic model. By using LaSalle's invariance principle and Lyapunov direct method, the global stability of equilibria is completely established. If there is no input of infectious individuals, the dynamical behaviors completely depend on the basic reproduction number. If there exists input of infectious individuals, the unique equilibrium of model is endemic equilibrium and is globally asymptotically stable. Once one place has imported a disease case, then it may become outbreak after that. Numerical simulations are presented to expound and complement our theoretical conclusions. [ABSTRACT FROM AUTHOR]

• The input population and output population are considered. • 108 scenarios are listed from the input population and quarantine strategies. • The second outbreak of disease is obtained. In this study, an epidemic model was developed to simulate and predict the disease variations of Guangdong province which was focused on the period from Jan 27 to Feb 20, 2020. To explore the impacts of the input population and quarantine strategies on the disease variations at different scenarios, four time points were assumed as Feb 6, Feb 16, Feb 24 and Mar 5 2020. The major results suggest that our model can well capture the disease variations with high accuracy. The simulated peak value of the confirmed cases is 1002 at Feb 10, 2020 which is mostly close to the reported number of 1007 at Feb 9, 2020. The disease will become extinction with peak value of 1397 at May 11, 2020. Moreover, the increased numbers of the input population can mainly shorten the disease extinction days and the increased percentages of the exposed individuals of the input population increase the number of cumulative confirmed cases at a small percentage. Increasing the input population and decreasing the quarantine strategy together around the time point of the peak value of the confirmed cases, may lead to the second outbreak. [ABSTRACT FROM AUTHOR]

This paper investigates the state-feedback stabilization of stochastic nonholonomic systems with an unknown time-varying delay. Without imposing any assumptions on the time-varying delay, a state-feedback controller is skillfully designed by using input-state-scaling technique and backstepping control approach. The switching strategy is proposed to eliminate the phenomenon of uncontrollability and to guarantee that the closed-loop system has an almost surely unique solution for any initial state and the equilibrium of interest is globally asymptotically stable in probability. A simulation example demonstrates the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

Per-/polyfluoroalkyl substances (PFASs), which are widely used in industrial and commercial products, have been identified as global and ubiquitous pollutants. Despite this, limited data are available regarding the impacts of PFAS exposure and intake in non-human primates. Here, we report for the first time on the occurrence of PFASs in the blood and dietary sources of two rare and endangered primate species, namely, the golden snub-nosed monkey (Rhinopithecus roxellana) and Francois' leaf monkey (Trachypithecus francoisi). Results showed that perfluorooctanoate (PFOA) and perfluorononanoate (PFNA) were dominant and found at the highest proportions in the blood of both species at the four study sites. The ∑PFAS levels in blood samples from captive golden snub-nosed monkeys in Tongling Zoo (mean: 2.51 ng/mL) and Shanghai Wild Zoo (3.52 ng/mL) near urbanized areas were one order of magnitude higher than the levels in wild monkeys from Shennongjia Nature Reserve (0.27 ng/mL). Furthermore, significant age positive relationships for perfluorodecanoic acid (PFDA), perfluorooctane sulfonate (PFOS), and 6:2 chlorinated polyfluorinated ether sulfonates (6:2 Cl-PFESA) were observed in both golden snub-nosed monkeys at Shanghai Wild Zoo and Francois' leaf monkeys at Wuzhou Breeding Center. In addition, PFAS levels in frequently consumed food and drinking water were analyzed for Francois' leaf monkeys. Results showed that tree leaves accounted for the highest percentage of total daily intake of PFASs, especially PFOA, thus highlighting tree leaf consumption as a primary PFAS exposure route for this species. Overall, however, dietary exposure to PFASs was of relatively low risk to Francois' leaf monkey health. Unlabelled Image • PFOA and PFNA were the predominant compounds in two colobine monkeys' blood. • F-53B was also detected in monkey's blood. • Levels of PFDA, PFOS, FOSA and F-53B in monkey blood increased with its age. • PFASs in monkey mainly were intake from tree leaves. [ABSTRACT FROM AUTHOR]

This paper focuses on the global stability of an epidemic model with vaccination, treatment and isolation. The basic reproduction number R 0 is derived. By constructing suitable Lyapunov functions, sufficient conditions for the global asymptotic stability of equilibria are obtained. Numerical simulations are performed to verify and complement the theoretical results. Furthermore, we consider the uncertainty and sensitivity analysis of the basic reproduction number R 0 . The results show that the transmission rate, the fraction of infected receives treatment, vaccination rate, the isolation rate are crucial to prevent the spread of infectious diseases. These suggest that public health workers design the control strategies of disease should consider the influence of vaccination, treatment and isolation. [ABSTRACT FROM AUTHOR]

The one-pot synthesis of furfuryl ethyl ether (FEE) over Pd nanoparticles supported on TiO2, Al2O3, SiO2, and active carbon via the catalytic reductive etherification of furfural in ethanol was systematically studied. The Pd nanoparticles supported on SiO2, TiO2 and active carbon are all active for this novel process under mild reaction conditions, with Pd/C showing the highest selectivity to FEE. The effects of palladium loading, reaction temperature, and hydrogen pressure on the activity and selectivity of Pd/C have been investigated in detail. The results demonstrate that suitable Pd amount, low reaction temperature of about 60 °C, and low H2 pressure of about 0.3 MPa are favorable for the formation of the desired ether product. Under the optimized conditions, an unprecedented high yield of up to 81% of FEE was firstly obtained with the major by-products being furfuryl alcohol and 2-methyltetrahydrofuran. Compared with the conventional hydrogenation-etherification route via furfural alcohol as a reaction intermediate, the reductive etherification shows significant advantage in product yield because of its much lower reaction temperature that is required. [ABSTRACT FROM AUTHOR]

Saturated fluorotelomer carboxylic acids (FTCAs) are intermediates in the degradation of fluorotelomer alcohols (FTOHs) to perfluorinated carboxylic acids (PFCAs). Recent studies have detected FTCAs in precipitation, surface waters, and wildlife, but few studies have focused on their toxicity. In this study, zebrafish embryos were exposed to different concentrations of 6:2 FTCA (0, 4, 8, and 12 mg/L) from 6 to 120 h post-fertilization (hpf) to investigate its developmental toxicity. Results showed that 6:2 FTCA exposure decreased the hatching and survival percentages, reduced the heart rate, and increased the malformation of zebrafish embryos. The median lethal concentration of 6:2 FTCA was 7.33 mg/L at 120 hpf, which was lower than that of perfluorooctanoic acid (PFOA), thus indicating higher toxicity for zebrafish. The most common developmental malformation was pericardial edema, which appeared in the 8 and 12 mg/L 6:2 FTCA-exposed embryos from 60 hpf. Using o-dianisidine staining, we found that the hemoglobin content in embryos was reduced in a concentration-dependent manner after 6:2 FTCA exposure at 72 hpf. Based on quantitative real-time polymerase chain reaction (q-RT-PCR) and whole-mount in situ hybridization, the transcriptional levels of hemoglobin markers ( hbae1 , hbbe1 , and hbae3 ) were down-regulated at 48 and 72 hpf, even though no observed malformation appeared in zebrafish at 48 hpf. Moreover, 6:2 FTCA exposure decreased the protein level of gata1 , a principal early erythrocytic marker, in Tg ( gata1 :DsRed) transgenic zebrafish at 72 hpf. We analyzed the transcriptional level of other erythrocyte-related genes using q-RT-PCR assay. For heme formation, the transcription of alas2 , which encodes the key enzyme for heme biosynthesis, was down-regulated after 6:2 FTCA exposure, whereas the transcription of ho-1 , which is related to heme degradation, was up-regulated at 48 and 72 hpf. The transcriptional patterns of gata1 and gata2 , which are related to erythroid differentiation, differed. At 48 hpf, the mRNA level of gata2 was significantly increased, whereas that of gata1 exhibited no significant changes in any treatment group. At 72 hpf, the expressions of both were down-regulated in a concentration-dependent manner. Taken together, 6:2 FTCA exposure decreased the erythrocyte number and disrupted erythroid differentiation during zebrafish embryonic development. Our results suggest that 6:2 FTCA can cause developmental toxicity in zebrafish embryos, and that FTCAs exhibit greater toxicity than that of PFCAs. [ABSTRACT FROM AUTHOR]

As an alternative to perfluorooctanesulfonate (PFOS), 6:2 chlorinated polyfluorinated ether sulfonate (commercial name: F-53B) has been used as a mist suppressant in Chinese electroplating industries for over 30 years. It has been found in the environment and fish, and one acute assay indicated F–53B was moderately toxic. However, the toxicological information on this compound was incomplete and insufficient for assessment of their environment impact. The object of this study was to examine the developmental toxicity of F–53B using zebrafish embryos. Zebrafish embryos were incubated in 6-well plates with various concentrations of F–53B (1.5, 3, 6, and 12 mg/L) from 6 to 132 h post fertilization (hpf). Results showed that F–53B exposure induced developmental toxicity, including delayed hatching, increased occurrence of malformations, and reduced survival. Malformations, including pericardial and yolk sac edemas, abnormal spines, bent tails, and uninflated swim bladders, appeared at 84 hpf, and increased with time course and dose. A decrease in survival percentages was noted in the 6 and 12 mg/L F-53B-treated groups at 132 hpf. Continuous exposure to 3 mg/L F–53B resulted in high accumulation levels in zebrafish embryos, suggesting an inability for embryos to eliminate this compound and a high cumulative risk to fish. We also examined the cardiac function of embryos at specific developmental stages following exposure to different concentrations, and found that F–53B induced cardiac toxicity and reduced heart rate. Even under low F–53B concentration, o-dianisidine staining results showed significant decrease of relative erythrocyte number at 72 hpf before the appearance of observed effects of F–53B on the heart. To elucidate the underlying molecular changes, genes involved in normal cardiac development were analyzed using real-time qPCR in the whole-body of zebrafish embryos. F–53B inhibited the mRNA expression of β-catenin ( ctnnb2 ) and wnt3a . The mRNA levels of β-catenin targeted genes ( nkx2.5 and sox9b ), which play critical roles in cardiogenesis, were also reduced after exposure. Thus, exposure to F–53B impaired the development of zebrafish embryos and disrupted cardiac development, which might be mediated by effects on the Wnt signaling pathway and decrease of erythrocyte numbers. [ABSTRACT FROM AUTHOR]

In this paper, we study a discrete susceptible-infected-removed epidemic model with vaccination and treatment and it is shown that the global dynamics is determined by the basic reproduction number. If, then the disease-free equilibrium is globally asymptotically stable and if, then the endemic equilibrium is globally asymptotically stable. [ABSTRACT FROM PUBLISHER]

Entomopathogenic fungus is proposed to be one of the best biocontrol agents against the destructive insect pest Plutella xylostella. In this study, we tested the virulence of 11 Metarhizium strain isolates against P. xylostella using a leaf dipping method, and found one strain, named 609, which had displayed the highest pathogenicity. Bioassay results showed that the accumulated corrected mortality rate was 86.7 % on the eighth day after inoculation with a spore concentration 1 × 10 conidia/mL, and that the time to 50 % lethality was 5.7-day. The strain was identified as Metarhizium anisopliae var. acridum by internal transcribed spacer (ITS) region sequencing. A green fluorescent protein (GFP) marker containing vector, camben-gfp, was constructed and delivered into strain 609 by Agrobacterium tumefaciens-mediated transformation. Six positive clones expressing GFP were selected and tested for toxicity against P. xylostella, all of which displayed the same toxicity as the parental wild type strain. The survival rate of transformant T1 was investigated by monitoring GFP levels at 4-day intervals after inoculation into soil. We found that the concentration of Metarhizium spores decreased sharply from 1 × 10 conidia/g to 1 × 10 conidia/g in the first 5 days after inoculation. The decreasing trend then stabilized and the spore count declined to approximately 1 × 10-10 conidia/g after 1 month. The results of this study indicate that the expression of gfp gene in strain 609 does not alter the virulence capability of Metarhizium. This strain will therefore be useful for the control of P. xylostella and as a tool to study molecular biology properties and monitor colonization of M. anisopliae in the field. [ABSTRACT FROM AUTHOR]

An non-standard finite difference scheme is employed to discuss a class of SIR epidemic model with vaccination and treatment. The dynamical properties of the discretized model are then analysed. The results demonstrate that the discretized epidemic model is dynamically consistent with the continuous model since it maintains essential properties of the corresponding continuous model, such as positivity property and boundness of solutions, equilibrium points and their local stability properties. [ABSTRACT FROM PUBLISHER]

[Display omitted] • 3D thin wall with turgor pressure finite element model of bacterial cell was build. • The AFM indentation experiments of E. coli cell were simulated using 3D-TWTP-FEM. • Investigation of mechano-bactericidal mechanism of nanostructured surfaces. • This study reveals the maximum stress location of the cells adhered to nanopillars. • Optimal nanopillar geometry for mechanically killing bacteria. The mechano-bactericidal property of nanostructured surfaces has become the focus of intensive research toward the development of a new generation of antibacterial surfaces, especially in the current era of spreading antibiotic resistance. However, the mechanisms underlying nanostructured surfaces mechanically damaging bacteria remain unclear, which ultimately limits translational potential toward real-world applications. Using finite element simulation technique, we developed the three-dimensional thin wall with turgor pressure finite element model (3D-TWTP-FEM) of bacterial cell and verified the reliability of this model by the AFM indentation experiment simulation of the cell, and the cell model is able to simulate suspended bacterial cell and the process of cell adhering to the flat and nanopillar surfaces. Since bacterial cells suffer greater stress and deformation on the nanopillar surfaces, a two-stage model of the elastic and creep deformation stage of the cells on the nanostructured surfaces was developed. The calculations show that the location of the maximum stress/strain on the cells adhered to the nanopillar surfaces is at the liquid-cell-nanopillar three phase contact line. The computational results confirmed the ability of nanostructured surfaces to mechanically lyse bacteria and gave the effect of nanopillar geometry on the efficiency and speed of bacterial cell rupture. This study provides fundamental physical insights into how nanopillar surfaces can serve as effective and fast mechanical antimicrobial materials. [ABSTRACT FROM AUTHOR]

Wuxiang virus (WUXV) is the first sandfly-borne Phlebovirus isolated from Phlebotomus chinensis collected in China and has been established as a consistent viral presence in the local sandfly populations of both Wuxiang County and Yangquan City. However, its distribution in the Shanxi Province remains unclear. In this study, three novel WUXV strains were isolated from sandflies collected from Jiexiu City, Shanxi Province, China, in 2022. Subsequently, whole-genome sequences of these novel strains were generated using next-generation sequencing. The open reading frame (ORF) sequences of the WUXV strains from the three locations were subjected to gene analysis. Phylogenetic analysis revealed that WUXV belongs to two distinct clades with geographical differences. Strains from Wuxiang County and Yangquan City belonged to clade 1, whereas strains from Jiexiu City belonged to clade 2. Reassortment and recombination analyses indicated no gene reassortment or recombination between the two clades. However, four reassortments or recombination events could be detected in clade 1 strains. By aligning the amino acid sequences, eighty-seven mutation sites were identified between the two clades, with seventeen, sixty, nine, and one site(s) in the proteins RdRp, M, NSs, and N, respectively. Additionally, selection pressure analysis identified 17 positively selected sites across the entire genome of WUXV, with two, thirteen, one, and one site(s) in the proteins RdRp, M, NSs, and N, respectively. Notably, sites M-312 and M-340 in the M segment not only represented mutation sites but also showed positive selective pressure effects. These findings highlight the need for continuous nationwide surveillance of WUXV. [ABSTRACT FROM AUTHOR]

Cigarette smoke aggravates severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) infection. However, the underlying mechanisms remain unclear. Here, they show that benzo[a]pyrene in cigarette smoke extract facilitates SARS‐CoV‐2 infection via upregulating angiotensin‐converting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS2). Benzo[a]pyrene trans‐activates the promoters of ACE2 and TMPRSS2 by upregulating nuclear receptor subfamily 4 A number 2 (NR4A2) and promoting its binding of NR4A2 to their promoters, which is independent of functional genetic polymorphisms in ACE2 and TMPRSS2. Benzo[a]pyrene increases the susceptibility of lung epithelial cells to SARS‐CoV‐2 pseudoviruses and facilitates the infection of authentic Omicron BA.5 in primary human alveolar type II cells, lung organoids, and lung and testis of hamsters. Increased expression of Nr4a2, Ace2, and Tmprss2, as well as decreased methylation of CpG islands at the Nr4a2 promoter are observed in aged mice compared to their younger counterparts. NR4A2 knockdown or interferon‐λ2/λ3 stimulation downregulates the expression of NR4A2, ACE2, and TMPRSS2, thereby inhibiting the infection. In conclusion, benzo[a]pyrene enhances SARS‐CoV‐2 infection by boosting NR4A2‐induced ACE2 and TMPRSS2 expression. This study elucidates the mechanisms underlying the detrimental effects of cigarette smoking on SARS‐CoV‐2 infection and provides prophylactic options for coronavirus disease 2019, particularly for the elderly population. [ABSTRACT FROM AUTHOR]

Here, we report on the occurrence of a novel perfluoroalkyl ether carboxylic acid, ammonium perfluoro-2-[(propoxy)propoxy]-1-propanoate (HFPO-TA), in surface water and common carp (Cyprinus carpio) collected from the Xiaoqing River and in residents residing near a fluoropolymer production plant in Huantai County, China. Compared with the levels upstream of the Xiaoqing River, HFPO-TA concentrations (5200-68500 ng/L) were approximately 120-1600-times higher downstream after receiving fluoropolymer plant effluent from a tributary. The riverine discharge of HFPO-TA was estimated to be 4.6 t/yr, accounting for 22% of total PFAS discharge. In the wild common carp collected downstream from the point source, HFPO-TA was detected in the blood (median: 1510 ng/mL), liver (587 ng/g ww), and muscle (118 ng/g ww). The log BCFblood of HFPO-TA (2.18) was significantly higher than that of PFOA (1.93). Detectable levels of HFPO-TA were also found in the sera of residents (median: 2.93 ng/mL). This is the first report on the environmental occurrence and bioaccumulation of this novel chemical. Our results indicate an emerging usage of HFPO-TA in the fluoropolymer manufacturing industry and raise concerns about the toxicity and potential health risks of HFPO-TA to aquatic organisms and humans. [ABSTRACT FROM AUTHOR]

In order to achieve rapid and sensitive detection of CYFRA 21-1, a signal-off photoelectrochemical (PEC) immunosensor was devised with NiCo 2 O 4 /CdIn 2 S 4 /In 2 S 3 heterojunction photoactive materials as sensing platform and ReS 2 @Au NPs as the secondary antibody labels amplifying signal based on the energy band-matching cascade structure and double suppression effect. NiCo 2 O 4 possessed a faster charge transfer rate due to the abundance of redox electron pairs (Co3+/Co2+ and Ni3+/Ni2+). To further improve the PEC properties of NiCo 2 O 4 under visible light, CdIn 2 S 4 with matching bandgap energy was selected to form heterojunction with NiCo 2 O 4 and sensitized with In 2 S 3. The proposed heterojunctions with well-matched band structure promoted the transfer of photo-generated carriers and were exploited as signal transducers for immobilization of antibodies and recognition of CYFRA 21-1. Furthermore, a novel urchin-like p-type ReS 2 semiconductor nanostructure functionalized by Au NPs was firstly used as a nanolabel to quench the signal. On the one hand, the Schottky heterojunction generated by ReS 2 and Au NPs could compete with the transducer substrate for both light and electron donors. On the other hand, the large space steric hindrance of ReS 2 prevented contact between the matrix and AA. Subsequently, the sensor was sensitive in a wide range of concentrations for CYFRA 21-1 (0.0001–50 ng/mL), and the detection limit was 0.05 pg/mL. [ABSTRACT FROM AUTHOR]

• Manganese-based ternary composite materials are proposed and synthesized by a facile method. • The obtained anode material exhibits an excellent rate capability of 533.2 mAh/g at 16 A/g and a good long-term cycling stability of 1700 mAh/g after 450 cycles under 1 A/g. • The enhanced electrochemical performance is attributed to the synergistic effect and abundant interfaces. The rate performance of anode materials is desirable for lithium-ion batteries (LIBs) in energy storage and electric vehicle applications. The composite of different transition metal oxides may improve the rate performance of anode materials for LIBs. Ternary metal oxide/acetylene black (Mn/Ni/Fe/AB) materials were prepared by co-precipitation with subsequent annealing treatment and mechanical ball milling. Compared with the binary metal oxides, the ternary metal oxide displays remarkably improved electrochemical performance with an excellent rate performance of 533.2 mAh/g at 16 A/g and a superior reversible capacity of 1700 mAh/g after 450 cycles under 1 A/g. The enhanced electrochemical performance is attributed to the multiphase interface and the synergistic effect in the ternary oxide materials. Considering the multi-component design, the manganese-based ternary oxides will be a promising anode material for superior performance in LIBs. [ABSTRACT FROM AUTHOR]

The adjuvant effect of ginsenoside Rg1 on immune responses against hepatitis B surface antigen (HBsAg) in mice was investigated. Female BALB/c mice were subcutaneously injected with saline or HBsAg antigen with or without Rg1 on days 7 and 21. Samples were collected 2 weeks after the boosting for the detection of anti-HBsAg immunoglobulin G (IgG) isotypes in sera and gamma interferon (IFN-γ) and interleukin-4 (IL-4) produced in splenocytes. The innate and adaptive immune responses were measured in mice immunized as described above. The results showed that ginsenoside Rg1 had adjuvant properties in stimulating IgG, splenocyte proliferation, and mRNA expression of cytokines IFN-γ and IL-4, as well as the expression of cell surface marker TLR4 in the HBsAg-immunized mice. These results indicate that Rg1 enhances both Th1 (IgG2b and IFN-γ) and Th2 (IgG1 and IL-4) responses. In addition, the TLR4 signaling pathway is involved in the adjuvant activities of ginsenoside Rg1. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are promising adsorbents for legacy per-/polyfluoroalkyl substances (PFASs), but they are being replaced by emerging PFASs. The effects of varying carbon chains and functional groups of emerging PFASs on their adsorption behavior on MOFs require attention. This study systematically revealed the structure-adsorption relationships and interaction mechanisms of legacy and emerging PFASs on a typical MOF MIL-101(Cr). It also presented an approach reflecting the average electronegativity of PFAS moieties for adsorption prediction. We demonstrated that short-chain or sulfonate PFASs showed higher adsorption capacities (μmol/g) on MIL-101(Cr) than their long-chain or carboxylate counterparts, respectively. Compared with linear PFASs, their branched isomers were found to exhibit a higher adsorption potential on MIL-101(Cr). In addition, the introduction of ether bond into PFAS molecule (e.g., hexafluoropropylene oxide dimeric acid, GenX) increased the adsorption capacity, while the replacement of CF 2 moieties in PFAS molecule with CH 2 moieties (e.g., 6:2 fluorotelomer sulfonate, 6:2 FTS) caused a decrease in adsorption. Divalent ions (such as Ca2+ and SO 4 2−) and solution pH have a greater effect on the adsorption of PFASs containing ether bonds or more CF 2 moieties. PFAS adsorption on MIL-101(Cr) was governed by electrostatic interaction, complexation, hydrogen bonding, π-CF interaction, and π-anion interaction as well as steric effects, which were associated with the molecular electronegativity and chain length of each PFAS. The average electronegativity of individual moieties (named M e) for each PFAS was estimated and found to show a significantly positive correlation with the corresponding adsorption capacity on MIL-101(Cr). The removal rates of major PFASs in contaminated groundwater by MIL-101(Cr) were also correlated with the corresponding M e values. These findings will assist with the adsorption prediction for a wide range of PFASs and contribute to tailoring efficient MOF materials. [Display omitted] • Short-chain, branched, or sulfonate PFAS show a higher adsorption on MIL-101(Cr). • In PFAS, ether bond aids its adsorption on MIL-101(Cr), but H/F exchanges weaken it. • Divalent ions and pH have a greater effect on more electronegative PFAS adsorption. • Electrostatic, complex, π-CF interactions, and steric effects govern PFAS adsorption. • Moiety electronegativity of each PFAS can be used for adsorption prediction on MOFs. [ABSTRACT FROM AUTHOR]

• We proposed a pulmonary tuberculosis transmission model by considering direct/ indirect infection and the difference between smear positive and negative individuals in transmission capability. • Basic reproduction number R 0 = 2.447 , indicating that the disease has been prevalent in Xinjiang during 2008–2017. • Control measures like early screening, isolating and treating the various types of pulmonary tuberculosis patients, and enhancing the clearance of Mycobacterium tuberculosis in the environment could effectively reduce the disease transmission in Xinjiang. Xinjiang has been one of the high incidence areas of pulmonary tuberculosis (PTB) in China. Besides being infected by direct contacting with active PTB individuals (direct infection), the susceptible would be infected because of the exposure to the environment contaminated by Mycobacterium tuberculosis (indirect infection). Active PTB individuals include not only the smear-positive PTB (PTB+) but also the smear-negative PTB (PTB–) who are infectious due to their ability to release tiny Mycobacterium tuberculosis particles even in the absence of visible Mycobacterium tuberculosis in sputum. By taking account of direct/indirect infection and the difference between PTB+ and PTB– individuals in transmission capability, a periodic dynamical PTB transmission model is proposed. The model is fitted to the newly monthly PTB+ and PTB– cases in Xinjiang from 2008 to 2017 by Markov Chain Monte Carlo algorithm. Moreover, global sensitivity analysis is constructed to address the uncertainty of some key parameters by using Latin hypercube sampling and partial rank correlation coefficient methods. Basic reproduction number R 0 for PTB transmission in Xinjiang is estimated to be 2.447 (95% CrI:(1.203, 3.844)), indicating that PTB has been prevalent in Xinjiang over the study period. Our results suggest that reducing the direct/indirect transmission rates, early screening, isolating and treating the latent, PTB+ and PTB– individuals, and enhancing the clearance of Mycobacterium tuberculosis in the environment could more effectively control PTB transmission in Xinjiang. The model fits the reported PTB data well and achieves acceptable prediction accuracy. We believe that our model can provide heuristic support for controlling PTB transmission in Xinjiang. [ABSTRACT FROM AUTHOR]

The ingestion of fruits containing perfluoroalkyl acids (PFAAs) presents potential hazards to human health. This study aimed to fill knowledge gaps concerning the tissue-specific distribution patterns and bioaccumulation behavior of PFAAs and their isomers, alternatives, and precursors (collectively as per-/polyfluoroalkyl substances, PFASs) within citrus trees growing in contaminated fields. It also assessed the potential contribution of precursor degradation to human exposure risk of PFASs. High concentrations of total target PFASs (∑PFASs target , 92.45–7496.16 ng/g dw) and precursors measured through the total oxidizable precursor (TOP) assay (130.80–13979.21 ng/g dw) were found in citrus tree tissues, and short-chain PFASs constituted the primary components. The total PFASs concentrations followed the order of leaves > fruits > branches, bark > wood, and peel > pulp > seeds. The average contamination burden of peel (∑PFASs target : 57.75%; precursors: 71.15%) was highest among fruit tissues. Bioaccumulation factors (BAFs) and translocation potentials of short-chain, branched, or carboxylate-based PFASs exceeded those of their relatively hydrophobic counterparts, while ether-based PFASs showed lower BAFs than similar PFAAs in above-ground tissues of citrus trees. In the risk assessment of residents consuming contaminated citruses, precursor degradation contributed approximately 36.07% to total PFASs exposure, and therefore should not be ignored. [Display omitted] • The levels of ∑PFASs in order are leaves > fruits > branches in citrus tree tissues. • Bark generally shows higher levels of individual PFASs than the corresponding wood. • Peel contributes the most pollution burden of PFASs in the whole citrus fruit. • Long-chain PFASs, linear isomers, and PFEAs show lower BAFs in citrus tree tissues. • Ignoring precursor degradation potentials will underestimate exposure risks of PFASs. [ABSTRACT FROM AUTHOR]

Breast cancer is the leading cause of tumor-associated death among women worldwide, and new therapeutic strategies are required to improve the post-surgery prognosis and quality of life of patients. Radiofrequency ablation (RFA) is a less invasive approach compared with traditional surgical resection to treat malignancies, and the combination of RFA and chemotherapeutic agents, including formosanin C (FC), can synergistically improve the curative effects against breast carcinoma. However, the detailed mechanisms remain unclear. In the present study, nude mice were used to identify the influence of FC on the therapeutic efficacy of RFA for breast cancer. Flow cytometry was performed to demonstrate the proportional alteration of CD8+ and CD45+ T cells with different biomarkers, including CD107a, IFNγ and TNFα. It was demonstrated that FC enhanced the therapeutic efficacy of RFA in breast cancer, while RFA combined with FC improved the proportion of IFNγ+ and TNFα+ CD8+ T cells and CD107a+ CD8+ T cells in tumor-infiltrating lymphocytes, thus increasing the immune responses caused by surgery and chemotherapy. The present study indicated that FC may promote the curative efficacy of ultrasound-guided RFA against breast tumor by regulating adaptive immune responses. [ABSTRACT FROM AUTHOR]

B Coronavirus Disease b Benzo[a]pyrene is a major active ingredient of cigarette smoke that induces the expression of a transcription factor, NR4A2, and promotes the binding of NR4A2 to promoters of ACE2 and TMPRSS2. Thus, benzo[a]pyrene promotes the infection of SARS-CoV-2 through up-regulating two receptors of SARS-CoV-2. Smoke and Spike: Benzo[a]pyrene Enhances SARS-CoV-2 Infection by Boosting NR4A2-Induced ACE2 and TMPRSS2 Expression (Adv. Sci. 26/2023). [Extracted from the article]

[Display omitted] • Crystal Structure of Two Non-competitive Nanobodies and SARS-CoV-2 RBD. • Two nanobodies neutralize SARS-CoV-2 including omicron variants by targeting ultra-conservative epitopes. • Developed a multivalent nanobody with high affinity and competitiveness. The evolving SARS-CoV-2 Omicron strain has repeatedly caused widespread disease epidemics, and effective antibody drugs continue to be in short supply. Here, we identified a batch of nanobodies with high affinity for receptor binding domain (RBD) of SARS-CoV-2 spike protein, separated them into three classes using high performance liquid chromatography (HPLC), and then resolved the crystal structure of the ternary complexes of two non-competing nanobodies (NB1C6 and NB1B5) with RBD using X-ray crystallography. The structures showed that NB1B5 and NB1C6 bind to the left and right flank of the RBD, respectively, and that the binding epitopes are highly conserved cryptic sites in all SARS-CoV-2 mutant strains, as well as that NB1B5 can effectively block the ACE2. These two nanobodies were covalently linked into multivalent and bi-paratopic formats, and have a high affinity and neutralization potency for omicron, potentially inhibiting viral escape. The binding sites of these two nanobodies are relatively conserved, which help guide the structural design of antibodies targeting future variants of SARS-CoV-2 to combat COVID-19 epidemics and pandemics. [ABSTRACT FROM AUTHOR]

Feature selection aims to select crucial features to improve classification accuracy in machine learning and data mining. Existing methods concentrate on the classification information from candidate features while seldom considering the changing information supported by selected features. In this paper, we construct a dynamic support ratio (DSR), which employs the new information of selected features to support classification. DSR explicitly describes the dynamic interactions between selected features and candidate features. Simultaneously, the feature relevance and feature redundancy are treated adaptively. Thus, distinctive features can be noticed sensitively. Afterward, a novel feature selection method based on a dynamic support ratio (DSRFS) is proposed. The proposed method is established on 18 benchmark data sets with four different classifiers. Classification accuracy, standard deviation, recall and statistical validations are employed to measure the classification performance. Extensive experiments demonstrate that DSRFS not only reduces the dimension of the feature space effectively, but also obtains the best average classification accuracy. [ABSTRACT FROM AUTHOR]

Abstract Although 6:2 chlorinated polyfluorinated ether sulfonate (F-53B), an alternative to perfluorooctanesulfonate (PFOS), has been regularly detected in different environmental matrices, information regarding its toxicity remains limited. To explore the transgenerational thyroid-disrupting capacity of F-53B, adult zebrafish (F0) were exposed to different concentrations of F-53B (0, 5, 50, or 500 μg/L) for 180 d, with their offspring (F1 and F2) subsequently reared in uncontaminated water. Thyroid disturbances were then examined in the three (F0, F1, and F2) generations. For F0 adult fish, thyroxine (T4) increased in both sexes after exposure to 50 μg/L F-53B, whereas 3,5,3′-triiodothyronine (T3) decreased in all groups, except for 50 μg/L F-53B-treated males. For F1 embryos, parental exposure resulted in F-53B transfer as well as an increase in T4 content. At 5 days post-fertilization, the significant increase in T4 and decrease in T3 were accompanied by a decrease in body length, increase in mortality, and increase in uninflated posterior swim bladder occurrence in F1 larvae. Although thyroid hormone levels were not changed significantly in F1 adult fish or F2 offspring compared with the control, the transcription levels of several genes along the hypothalamus-pituitary-thyroid axis were significantly modified. Our study demonstrated that F-53B possesses transgenerational thyroid-disrupting capability in zebrafish, indicating it might not be a safer alternative to PFOS. Graphical abstract Unlabelled Image Highlights • F-53B exposure disrupted the balance of thyroid hormone levels in F0 adult fish. • Increased T4 levels in F1 eggs were consistent with the T4 level of F0 female serum. • Parental exposed to F-53B altered THs and the HPT axis genes expression in F1 larvae. • Change of TH levels companied with defected swim bladder in F1 larvae. • The change of some HPT axis genes expression still present in F1 adult and F2 larvae. [ABSTRACT FROM AUTHOR]

As one of the receptors of the TAM family, AXL plays a vital role in stem cell maintenance, angiogenesis, immune escape of viruses and drug resistance against tumors. In this study, the truncated extracellular segment containing two immunoglobulin-like domains of human AXL (AXL-IG), which has been confirmed to bind growth arrest specific 6 (GAS6) by structural studies [1], was expressed in a prokaryotic expression system and then purified. Immunizing camelid with the purified AXL-IG as antigen could lead to the production of unique nanobodies composed of only variable domain of heavy chain of heavy-chain antibody (VHH), which are around 15 kD and stable. We screened out a nanobody A-LY01 specific binding to AXL-IG. We further determined the affinity of A-LY01 to AXL-IG and revealed that A-LY01 could specifically recognize full-length AXL on the surface of HEK 293T/17 cells. Our study provides appropriate support for the development of diagnostic reagents and antibody therapeutics targeting AXL. • AXL-IG protein was expressed in E. coli WK6. • A nanobody phage library was constructed. • A nanobody A-LY01 specifically binds to AXL was screened out by phage display technology. [ABSTRACT FROM AUTHOR]

For the diagnosis and therapy of small cell lung cancer (SCLC), the accurate and sensitive determination of neuron-specific enolase (NSE) content is crucial. This work outlines a dual-quenching electrochemiluminescence resonance energy transfer (ECL-RET) immunosensor based on the double quenching effects of iron base metal organic frameworks (FeMOFs) loaded with small sized CuO nanoparticles (FeMOFs-sCuO) towards CoPd nanoparticles (CoPdNPs) enhanced porous g-C 3 N 4 (P–C 3 N 4 -CoPdNPs). To be specific, we prepared a porous g-C 3 N 4 (P–C 3 N 4) which has a rich porous structure, and significantly increased the specific surface area and the number of reaction sites of P–C 3 N 4. Meanwhile, the CoPdNPs were loaded onto P–C 3 N 4 to improve the ECL luminescence property of P–C 3 N 4 /K 2 S 2 O 8 system through acting as a coreaction accelerator. In addition, the ultraviolet–visible (UV–vis) absorption spectra of FeMOFs and small sized CuO nanoparticles (sCuO) showed considerable overlap with the ECL emission spectra of P–C 3 N 4 appropriately. Therefore, FeMOFs with high specific surface area were prepared and well combined with sCuO to effectively dual-quenching the ECL emission of P–C 3 N 4 based on resonance energy transfer. Hence, a new type ECL-RET couple made up of P–C 3 N 4 -CoPdNPs (donor) and FeMOFs-sCuO (acceptor) were developed for the first time. A certain amount of P–C 3 N 4 -CoPdNPs, Ab 1 , BSA, NSE were modified layer by layer onto the electrode surface. Then FeMOFs-sCuO-Ab 2 bioconjugates was incubated through the immune recognition binding. As a result, a sandwich-type ECL biosensor was manufactured successfully for NSE immunoassay. Under optimal experimental conditions, the limit of detection (LOD) and the limit of quantitation (LOQ) of the prepared ECL sensor for NSE analysis was 20.4 fg mL−1 and 7.99 fg mL−1, respectively, with the relative standard deviation (RSD) of 1.68%. The linear detection range was 0.0000500–100 ng mL−1. The studied immunosensor had satisfactory sensitivity, specificity and reproducibility, manifesting the suggested sensing strategy might offer a good technical means and theoretical basis for the sensitivity analysis of NSE and has a potential application in clinical diagnosis analysis. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFASs) may cross the placental barrier and lead to fetal exposure. However, little is known about the factors that influence maternal-fetal transfer of these chemicals. PFAS concentrations were analyzed in 100 paired samples of human maternal sera collected in each trimester and cord sera at delivery; these samples were collected in Wuhan, China, 2014. Linear regression was used to estimate associations of transfer efficiencies with factors. Chlorinated polyfluorinated ether sulfonates (Cl-PFAESs, 6:2 and 8:2) were frequently detected (>99%) in maternal and cord sera. A significant decline in PFAS levels during the three trimesters was observed. A U-shape trend for transfer efficiency with increasing chain length was observed for both carboxylates and sulfonates. Higher transfer efficiencies of PFASs were associated with advancing maternal age, higher education, and lower glomerular filtration rate (GFR). Cord serum albumin was a positive factors for higher transfer efficiency (increased 1.1-4.1% per 1g/L albumin), whereas maternal serum albumin tended to reduce transfer efficiency (decreased 2.4-4.3% per 1g/L albumin). Our results suggest that exposure to Cl-PFAESs may be widespread in China. The transfer efficiencies among different PFASs were structure-dependent. Physiological factors (e.g., GFR and serum albumin) were observed for the first time to play critical roles in PFAS placental transfer. [ABSTRACT FROM AUTHOR]

Feature selection is a crucial preprocessing technique in data mining and machine learning and has attracted increasing attentions. However, the relevance of existing methods only contains limited information. To enhance the classification ability of filter and information theory-based feature selection methods and reduce the redundancy of the selected subset, a relevant-redundant weight-based feature criterion (FSRRW) is proposed. In this paper, a feature relevant-redundant weight (RRW) is constructed to extract the important relevant and redundant information. Then, a novel feature relevance is defined based on the weight, which contains more comprehensive information from the dynamically changing features. Additionally, a feature evaluation criterion is presented via maximizing the feature relevance and minimizing the feature redundancy. The proposed algorithm and seven compared methods are tested on 20 benchmark datasets. Extensive experiments demonstrate that the proposed criterion exhibits better feature screening abilities, effectively facilitates classification, and has preferable applicability and robustness. • Design a feature relevant-redundant weight and define feature relevance. • Construct a novel feature evaluation criterion named FSRRW. • FSRRW is evaluated on 20 benchmark datasets under three classifiers. • The proposed method outperforms seven popular feature selection methods. [ABSTRACT FROM AUTHOR]

This work presents a dual-quenching electrochemiluminescence resonance energy transfer (ECL-RET) immunosensor on account of the double quenching effects of polydopamine coated ZnO nanoflowers (ZnONFs@PDA) loaded with small-sized copper oxide nanoparticles (sCuO), named ZnONFs@PDA-sCuO, towards gold dendrite@polypyrrole core–shell nanoparticles (AuD@PPy) enhanced g-C 3 N 4 (g-C 3 N 4 -AuD@PPy) for sensitive analysis of procalcitonin (PCT). To be specific, AuD@PPy with core-shell structure were loaded onto g-C 3 N 4 to enhance the emission performance of g-C 3 N 4. In addition, the ultraviolet absorption spectra of ZnONFs@PDA and sCuO showed considerable overlap with the ECL emission spectra of g-C 3 N 4 appropriately. So sCuO and ZnONFs@PDA were combined and designed as an efficient dual-quencher of ECL luminescence of g-C 3 N 4 by RET interaction. The biosensor showed superior linear detection range from 0.00005 to 50 ng mL−1, with a sensitive detection limit of 17.2 fg mL−1 (S/N = 3). It is worthy to note that a new type ECL-RET couple made up of g-C 3 N 4 -AuD@PPy (donor) and ZnONFs@PDA-sCuO (acceptor) was developed to construct a sandwich ECL biosensor for PCT detection. The studied immunosensor had satisfactory sensitivity, specificity and reproducibility, indicating the proposed sensing method could provide a good technical means and theoretical basis for the diagnosis of serious diseases. • A new ECL-RET donor-receptor was proposed and fabricated for ultrasensitive detection of PCT. • AuD@PPy nanocomposites with core-shell structure were loaded onto g-C3N4 to enhance the ECL emission performance. • ZnONFs@PDA-sCuO was firstly used as an efficient dual-quenching prober of ECL signal. • The designed immunosensor exhibited low detection limit of 17.2 fg mL-1 for PCT. [ABSTRACT FROM AUTHOR]

TiO2, molecularly imprinted TiO2(TiO2/OTC) and a novel Si doped molecularly imprinted TiO2(TiO2/SiO2/OTC) nano photocatalytic materials were prepared by liquid phase deposition method. The products were characterized by XRD and SEM. The photocatalytic activities of the samples were evaluated by the photocatalytic degradation of oxytetracycline wastewater under a xenon lamp irradiation. The results showed that TiO2/SiO2/OTC and TiO2/OTC could improve both the photocatalytic activity and the molecular recognition ability, while the photocatalytic activities of TiO2/SiO2/OTC sample was more effective than TiO2/OTC sample with 5 times reuse. The photocatalytic activity of TiO2/SiO2/OTC photocatalyst sample had a greater improvement and its photocatalytic degradation of oxytetracycline wastewater reached 80.79% in 120 minute reaction. [ABSTRACT FROM PUBLISHER]

Perfluorooctane sulfonate (PFOS) is a commonly used and widely distributed perfluorinated compound proven to cause adverse health outcomes. However, how PFOS affects liver cell proliferation is not well understood. In this experiment, we exposed a human liver cell line (HL-7702) to 50 μM PFOS for 48 h and 96 h. We identified 52 differentially expressed proteins using a quantitative proteomic approach. Among them, 27 were associated with cell proliferation, including hepatoma-derived growth factor (Hdgf) and proliferation biomarkers Mk167 (Ki67) and Top2α. Results from MTT, cell counting, and cell cycle analysis showed low-dose PFOS (<200 μM) stimulated HL-7702 cell viability at 48 h and 96 h, reduced the G0/G1 percentage, and increased the S + G2/M percentage. Moreover, levels of Cyclin D1, Cyclin E2, Cyclin A2, Cyclin B1 and their partner Cdks were elevated, and the expression of regulating proteins like c-Myc, p53, p21 waf/cip1 and Myt1, as well as the phosphorylation levels of p-Wee1(S642), p-Chk1(S345) and p-Chk2(T68), were disturbed. We hypothesized that low-dose PFOS stimulated HL-7702 proliferation by driving cells into G1 through elevating cyclins/cdks expression, and by promoting cell cycle progression through altering other regulating proteins. This research will shed light on the mechanisms behind PFOS-mediated human hepatotoxicity. [ABSTRACT FROM AUTHOR]

Liquid–liquid equilibrium (LLE) data for quaternary systems containing ethanol + 2-propanol + salt [(NH 4 ) 2 SO 4 /Na 2 SO 4 ] + water were experimentally determined at 308.15, 318.15 and 328.15 K. Binodal curves were fitted to four empirical nonlinear equations, whereas tie-lines were fitted to the Setschenow-type equation and its temperature-dependent expression as well as another two-parameter equation. All of the models were successfully correlated with the experimental data. Factors affecting the phase-forming abilities of the investigated systems were also studied, such as the temperature, mass fraction of ethanol in the alcohol mixture and type of salt. The effective excluded volume values for the studied systems also were determined to evaluate the phase separation abilities of investigated systems. These data can be used for the development and design of extraction processes utilizing such systems. [ABSTRACT FROM AUTHOR]

Because of the evolutionary variants of SARS-CoV-2, development of broad-spectrum neutralizing antibodies resilient to virus escape is urgently needed. We identified a group of high-affinity nanobodies from camels immunized with receptor-binding domain (RBD) of SARS-CoV-2 spike protein and resolved the structures of two non-competing nanobodies (NB1A7 and NB1B11) in complex with RBD using X-ray crystallography. The structures show that NB1A7 targets the highly conserved cryptic epitope shared by SARS-CoV-2 variants and some other coronaviruses and blocks ACE2 receptor attachment of the spike protein, and NB1B11 epitope overlaps with the contacting surface of ACE2 and is different from the binding site of NB1A7. These two nanobodies were covalently linked into multivalent and bi-paratopic formats, which significantly improved the avidity and neutralization potency and may further inhibit viral escape. The results contribute to the structure-guided design of antibodies against future variants of SARS-CoV-2 virus to combat coronavirus epidemics and pandemics. [Display omitted] • Two neutralizing nanobodies are generated against the RBD of SARS-CoV-2 • The crystal structures reveal that the two nanobodies have different epitopes • One nanobody targets the highly conserved epitope • Bispecific nanobodies improve neutralization potency to SARS-CoV-2 variants Shi et al. identify two neutralizing nanobodies against SARS-CoV-2. Crystal structures reveal how they prevent the virus and its variants from entering cells. The combination of two nanobodies significantly improves neutralization potency, which is a potential therapeutic candidate to reduce the probability of the emergence of escape variants of SARS-CoV-2. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two plasma proteins were adsorbed on three typical TiO 2 nanostructures. • Surface topographies of nanostructures can be affected by protein adsorption. • Bactericidal performance of nanostructures is weakened due to the changes in geometric dimensions after BSA adsorption. • Bactericidal efficiency of nanostructures against E. coli can be significantly improved due to the presence of HFN layer on the top of the nanostructures, which may cause higher stress of nanocones to cell membrane. Bionic nanostructures have broad potential applications for achieving the surface mechano-bactericidal performance especially for titanium extensively used as implants. However, the surface topographies of these nanostructures may be changed by protein adsorption in vivo, which possibly affects the sterilization of nanostructures. Herein, two plasma proteins, bovine serum albumin (BSA) and human serum fibronectin (HFN), were adsorbed onto three typical TiO 2 nanostructures respectively, and the topographies as well as the subsequent bacterial behavior of Escherichia coli and Staphylococcus aureus were investigated. The results show that after BSA adsorption, the height of the nanostructures is reduced and the radius of the nanocones is increased for three typical nanostructures, weakening the surface bactericidal performance. Whereas, after HFN adsorption, the proteins are adsorbed at different positions of nanostructures, affecting their bactericidal efficiency. Notably, the bactericidal efficiency of nanowire clusters and nanowire/sheet clusters against Escherichia coli is significantly improved from ∼ 49.64% and ∼ 83.25% to ∼ 64.89% and ∼ 93.67% due to the presence of HFN layer on the top of the nanostructures, which may cause higher stress to cell membrane by nanocones. Our results demonstrate that the bactericidal performance of implant is impacted by the combined effect of surface nanostructure and protein layer. [ABSTRACT FROM AUTHOR]

• A new ECL-RET donor-receptor was proposed and fabricated for ultrasensitive detection of PCT. • IRMOF-3 not only acted as a carrier for N-GQDs by internal encapsulation and external decoration, but also a coreaction accelerator. • ZnO@Au nanorod was firstly applied as a dual-quenching prober of ECL signal. • The designed immunosensor exhibited low detection limit of 12.58 fg mL−1 for PCT. Herein a novel electrochemiluminescence resonance energy transfer (ECL-RET) pair of isoreticular metal organic framework-3 (IRMOF-3) enriched nitrogen-doped graphene quantum dots (N-GQDs) luminescent material (N-GQDs@IRMOF-3@N-GQDs, donor) and Au nanoparticles modified zinc oxide nanorod (ZnO@Au, acceptor) were firstly designed to fabricate a dual-quenching sandwich-type ECL immunosensor for ultrasensitive analysis of procalcitonin (PCT). IRMOF-3 not only acted as a carrier for abundantly enriching luminescent N-GQDs by internal encapsulation and external decoration, but also a coreaction accelerator which could boost the transformation of persulfate ion S 2 O 8 2− to generate more anion radical SO 4 −, so as to promote the ECL emission of N-GQDs. Additionally, Au nanoparticles were loaded onto the ZnO nanorods through in-situ modification to obtain ZnO@Au, which was firstly applied as a dual-quencher of ECL signal. In the best test environment, a wide detection range from 0.0001 to 100 ng mL−1 was obtained and the limit of detection is 12.58 fg mL−1 (S/N = 3). With excellent reproducibility and sensitivity, the practical test consequence of PCT in human serum samples was satisfactory. These results suggested that this sensing system could provide a reference model for effective detection of disease markers in clinical medicine. [ABSTRACT FROM AUTHOR]

Experimental studies suggested per- and polyfluoroalkyl substances (PFASs) may disrupt estrogens in animals, however, the epidemiological evidence on the associations of PFASs with estrogens is sparse. We investigated the associations of legacy PFASs and their alternatives, including F-53B, the perfluorooctane sulfonate (PFOS) replacement that is specifically and commonly used in China, with estrogen concentrations in newborns. We quantified six PFASs and three estrogens in the cord sera of 942 newborns from a birth cohort in Wuhan, China, between 2013 and 2014. After adjusting for confounders and correcting for multiple comparisons, we observed that both legacy PFASs and their alternatives were associated with higher serum levels of estradiol (E2). Some of the PFASs were associated with increasing levels of estrone (E1) and estriol (E3). Analysis of PFASs in mixture using weighted quantile sum regressions showed that F-53B contributed 20.1% and 48.5% to the associations between PFASs and E1 and E2, respectively. This study provided epidemiological data on the associations between common PFAS exposures and estrogens in newborns. Additional toxicology studies are needed to fully understand the effects of PFASs on estrogens and the mechanisms. ga1 • 6:2 Cl-PFESA, trade name F-53B, is a PFOS alternative specifically used in China. • 6:2 Cl-PFESA has ranked as 3rd highest PFASs exposed Chinese neonates. • Associations between 6 PFASs and 3 estrogen levels in neonates were assessed. • Both legacy PFASs and the alternatives were related to higher estrogen levels in cord sera. • 6:2 Cl-PFESA weighted more than PFOS and PFOA in association with estradiol in neonates. [ABSTRACT FROM AUTHOR]

• Associations between 11 PFASs and 5 steroids in cord sera were assessed. • F-53B, as Chinese unique PFOS replacement, was associated with cortisol in girls. • PFBS, PFOS and PFHxS were positively associated with progesterone in newborns. • Seven PFASs were positively associated with 11-deoxycortisol, the precursor of cortisol. • The results indicate that PFOS and its replacements may influence neonatal steroids. Exposure to per-/polyfluoroalkyl substances (PFASs) can disrupt endocrine hormones in humans. Prior studies have focused on the harmful effects of the two traditional per-/polyfluoroalkyl substances (PFASs), perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). Other PFASs, used as the replacements of PFOS and PFOA, are widely and increasingly detected in humans. Whether these replacements influence glucocorticoids and progestogens in newborns remains unknown. To investigate the associations between exposures of PFOS, PFOA and their replacements and glucocorticoids and progestogens in newborns. We measured the concentrations of 13 PFASs, 3 glucocorticoids (11-deoxycortisol, cortisol and cortisone) and 2 progestogens [progesterone, 17-hydroxyprogesterone (17OHP)] in the cord sera of 374 neonates in a birth cohort from Wuhan, China, between 2013 and 2014. We evaluated the associations of each PFAS with glucocorticoids and progestogens using multiple linear regression models, and multiple comparisons were additionally corrected via false discovery rates (FDR). Out of the 13 PFASs, 9 were detected in over 95% of cord sera. The Chinese specific PFOS replacement − 6:2 chlorinated polyfluorinated ether sulfonate (6:2 Cl-PFESA, trade name F-53B) was positively associated with 13.13% change in cortisol in girls (95% CI = 4.47%, 22.52%, for each IQR increase in 6:2 Cl-PFESA). Seven PFASs had positive associations with the precursor of cortisol, namely 11-deoxycortisol (percent change ranged from 6.41% to 11.24%, for each IQR increase in PFASs). Perfluorobutane sulfonate (PFBS) in cord sera was positively associated with progesterone in the linear model, whereas PFOS and perfluorohexane sulfonate (PFHxS) levels were associated with progesterone in the quartile models. No PFASs were related to 17OHP or cortisone. In this study, PFOS, PFOA and/or their replacements were positively associated with progesterone, cortisol and 11-deoxycortisol in newborns. These results suggested that not only PFOS and PFOA, but also other PFASs have potential impacts on glucocorticoids and progestogens in newborns. [ABSTRACT FROM AUTHOR]

Background: A clear understanding of the blood vessels in the eye is helpful in the diagnosis and treatment of ophthalmic diseases, such as glaucoma. Conventional techniques such as micro-CT imaging and histology are not sufficiently accurate to identify the vessels in the eye, because their diameter is just a few microns. The newly developed medical imaging technology, X-ray phase-contrast imaging (XPCI), is able to distinguish the structure of the vessels in the eye. In this study, XPCI was used to identify the internal structure of the blood vessels in the eye.Methods: After injection with barium sulfate via the ear border artery, an anesthetized rabbit was killed and its eye was fixed in vitro in 10% formalin solution. We acquired images using XPCI at the Shanghai Synchrotron Radiation Facility. The datasets were converted into slices by filtered back-projection (FBP). An angiographic score was obtained as a parameter to quantify the density of the blood vessels. A three-dimensional (3D) model of the blood vessels was then established using Amira 5.2 software.Results: With XPCI, blood vessels in the rabbit eye as small as 18 μm in diameter and a sixth of the long posterior ciliary artery could be clearly distinguished. In the 3D model, we obtained the level 4 branch structure of vessels in the fundus. The diameters of the arteria centralis retinae and its branches are about 200 μm, 110 μm, 95 μm, 80 μm and 40 μm. The diameters of the circulus arteriosus iridis major and its branches are about 210 μm, 70 μm and 30 μm. Analysis of vessel density using the angiographic score showed that the blood vessels had maximum density in the fundus and minimum density in the area anterior to the equator (scores 0.27 ± 0.029 and 0.16 ± 0.032, respectively). We performed quantitative angiographic analysis of the blood vessels to further investigate the density of the vessels.Conclusions: XPCI provided a feasible means to determine the structure of the blood vessels in the eye. We were able to determine the diameters and morphological characteristics of the vessels from both 2D images and the 3D model. By analyzing the images, we obtained measurements of the density distribution of the microvasculature, and this approach may provide valuable reference information prior to glaucoma filtration surgery. [ABSTRACT FROM AUTHOR]