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Background: Oral ingestion, inhalation, and skin contact are important exposure routes for humans to uptake per- and polyfluoroalkyl substances (PFAS). However, nasal and dermal exposure to PFAS remains unclear, and accurately predicting internal body burden of PFAS in humans via multiple exposure pathways is urgently required. Objectives: We aimed to develop multiple physiologically based toxicokinetic (PBTK) models to unveil the route- specific pharmacokinetics and bioavailability of PFAS via respective oral, nasal, and dermal exposure pathways using a mouse model and sought to predict the internal concentrations in various tissues through multiple exposure routes and extrapolate it to humans. Methods: Mice were administered the mixed solution of perfluorohexane sulfonate, perfluorooctane sulfonate, and perfluorooctanoic acid through oral, nasal, and dermal exposure separately or jointly. The time-dependent concentrations of PFAS in plasma and tissues were determined to calibrate and validate the individual and combined PBTK models, which were applied in single- and repeated-dose scenarios. Results: The developed route-specific PBTK models successfully simulated the tissue concentrations of PFAS in mice following single or joint exposure routes as well as long-term repeated dose scenarios. The time to peak concentration of PFAS in plasma via dermal exposure was much longer (34.1-83.0 h) than that via nasal exposure (0.960 h). The bioavailability of PFAS via oral exposure was the highest (73.2%-98.0%), followed by nasal (33.9%-66.8%) and dermal exposure (4.59%-7.80%). This model was extrapolated to predict internal levels in human under real environment. Discussion: Based on these data, we predict the following: PFAS were absorbed quickly via nasal exposure, whereas a distinct hysteresis effect was observed for dermal exposure. Almost all the PFAS to which mice were exposed via gastrointestinal route were absorbed into plasma, which exhibited the highest bioavailability. Exhalation clearance greatly depressed the bioavailability of PFAS via nasal exposure, whereas the lowest bioavailability in dermal exposure was because of the interception of PFAS within the skin layers. https://doi.org/10.1289/EHP11969, Introduction Since the 1950s, per- and polyfluoroalkyl substances (PFAS) have been widely used in a variety of industrial and household fields owing to their excellent surface activity, thermal and chemical [...]

Throughout the COVID‐19 pandemic, rhinovirus (RV) remained notable persistence, maintaining its presence while other seasonal respiratory viruses were largely suppressed by pandemic restrictions during national lockdowns. This research explores the epidemiological dynamics of RV infections among pediatric populations on Hainan Island, China, specifically focusing on the impact before and after the zero‐COVID policy was lifted. From January 2021 to December 2023, 19 680 samples were collected from pediatric patients hospitalized with acute lower respiratory tract infections (ARTIs) at the Hainan Maternal and Child Health Hospital. The infection of RV was detected by tNGS. RV species and subtypes were identified in 32 RV‐positive samples representing diverse time points by analyzing the VP4/VP2 partial regions. Among the 19 680 pediatric inpatients with ARTIs analyzed, 21.55% were found to be positive for RV infection, with notable peaks observed in April 2021 and November 2022. A gradual annual decline in RV infections was observed, alongside a seasonal pattern of higher prevalence during the colder months. The highest proportion of RV infections was observed in the 0–1‐year age group. Phylogenetic analysis on 32 samples indicated a trend from RV‐A to RV‐C in 2022. This observation suggests potential evolving dynamics within the RV species although further studies are needed due to the limited sample size. The research emphasizes the necessity for ongoing surveillance and targeted management, particularly for populations highly susceptible to severe illnesses caused by RV infections. [ABSTRACT FROM AUTHOR]

Objective:To study the species of ticks found on cattle in Hainan and the prevalence of Anaplasma carried by these ticks. Methods:This study selected nine counties and cities in the central and northern parts of Hainan as sampling points to collect tick samples from cattle. Tick species were identified through morphological observation and molecular biological techniques. The presence of Anaplasma pathogens was detected using PCR with 16S rRNA, groEL, and gltA as target genes. Phylogenetic analysis methods were further employed to reveal the interspecies relationships of Anaplasma carried by ticks on cattle in Hainan. Results:A total of 335 ticks were collected in this study, including 44 Rhipicephalus sanguineus and 291 Rhipicephalus microplus. PCR results indicated the presence of Candidatus Anaplasma boleense and Anaplasma marginale in the ticks, with positivity rates of 0.60% (2/335) and 0.90% (3/335), respectively. Phylogenetic analysis showed that the Anaplasma obtained in this experiment were homologous to known Anaplasma species. Conclusion:The dominant tick species on cattle in Hainan is Rhipicephalus microplus. The ticks were found to carry Anaplasma pathogens, and this study provides important data support for the prevention and treatment of Anaplasma diseases in the region. [ABSTRACT FROM AUTHOR]

Objective: To develop a TTV detection technique with higher sensitivity and specificity, providing crucial technical support for uncovering the role of TTV in process of various diseases. Methods: For more accurate and sensitive TTV detection, this study analyzed all published subtypes of TTV genome sequences, on the basis of which a real-time PCR assay targeting the UTR was established and compared with the more widely used PCR assays reported in the references. Results: The method established in this study showed good linear relationship within the range of 1 x 107 to 1 x 101 copies/µ L standard sample concentrations, with a correlation coefficient of 1.000, a slope of -3.446, and a detection limit of 1 x 101 copies/µ L. The repeatability test results demonstrated an intra-assay coefficient of variation of 7.22%, indicating strong repeatability and stability of the method. Compared with four sets of primers widely used in previous studies, our established real-time PCR detection method showed significantly higher sensitivity (P<0.01) in detecting 30 clinical samples. Sanger sequencing results confirmed that all 30 positive samples detected by our method were TTV-positive, with a detection specificity of 100%. Conclusion: This study adopts a realtime PCR detection method based on the TaqMan probe, which has high sensitivity and wide coverage of genotype range, especially for quantitative detection in cases of low TTV viral load. It provides important technical support for the pathogenicity of the TTV virus and its application as an immune marker. [ABSTRACT FROM AUTHOR]

According to characteristics of dynamic time sequence, complexity and uncertainty of coal mine production logistics system, security resources index system of coal mine production logistics system was determined that fully considered objective factors of various subsystems of the coal mine production logistics system, and security resources index was quantitatively calculated and analyzed by information entropy method. The safety resource allocation model based on maximum information entropy was built, and the optimization allocation problem of security resources was studied. Application results of example show that transportation subsystem and drainage subsystem belong to focus on increasing security resources investment, and mining subsystem and ventilation subsystem belong to cut safety resource investment. The safety resource allocation based on maximum information entropy method can provide theoretical support for improving level of coal mine safety production and optimizing coal mine security resource allocation.

The aza‐Prins cyclization reaction catalyzed by ZrCl4 and NHC (N‐heterocyclic carbene) metal complexes is firstly reported. NHC‐copper complexes as promoter and ZrCl4 as chloride source are utilized under a mild condition, where homoallylic amines and aldehydes are successfully converted to piperidine derivatives in satisfactory yields and diastereoselectivity. [ABSTRACT FROM AUTHOR]

The aza‐Prins cyclization reaction catalyzed by ZrCl4 and NHC (N‐heterocyclic carbene) metal complexes is firstly reported. NHC‐copper complexes as promoter and ZrCl4 as chloride source are utilized under a mild condition, where homoallylic amines and aldehydes are successfully converted to piperidine derivatives in satisfactory yields and diastereoselectivity. [ABSTRACT FROM AUTHOR]