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Objectives: The objective of this study is to compare the incidence and clinical characteristics of severe pneumonia caused by Human metapneumovirus (hMPV) to respiratory syncytial virus (RSV) infection in children. Patients and Methods: A total of 151 children hospitalized with severe pneumonia, were tested for hMPV using reverse-transcription polymerase chain reaction. At the same time, samples were tested for RSV and other common respiratory viruses. Medical records, including clinical, laboratory data, and chest radiography findings, were reviewed for all children. Results: Of the 151 samples, 88 (58.3%) were positive for respiratory viruses. Of the 88 positive, there were 6 (4.0%) with hMPV, 66 (43.7%) with RSV, 13 (8.6%) with influenza A, 2 (1.3%) with parainfluenza virus III, 1 (0.7%) with parainfluenza virus I, 1 (0.7%) with adenovirus and 1 (0.7%) with influenza B. hMPV-infected patients were significantly older than RSV-infected patients (P < 0.001). Children with hMPV pneumonia had fever more frequently (P = 0.03). Two hMPV-positive patients (33.3%) required admission to an intensive care unit, and two patients (33.3%) required mechanical ventilation. The duration of illness was 18.33 ± 7.09 days. These characteristics of hMPV infections were similar to patients with RSV infections. Conclusion: Human metapneumovirus is an infrequent viral pathogen causing severe pneumonia in children. Children with hMPV were older than those with RSV. The disease caused by hMPV was similar in presentation and severity to RSV, with a minority of children requiring additional respiratory support.

Natural hematopoietic stem cells (HSC) are susceptible and tend to lose stemness, differentiate, or die on culture condition in vitro, which adds technical challenge for maintaining bona fide HSC-like cells, if ever generated, in protocol screening from pluripotent stem cells. It remains largely unknown whether gene-editing of endogenous genes can genetically empower HSC to endure the culture stress and preserve stemness. In this study, we revealed that both NUP98-HOXA10HD fusion and endogenous Nras mutation modifications (NrasG12D) promoted the engraftment competitiveness of HSC. Furthermore, the synergy of these two genetic modifications endowed HSC with super competitiveness in vivo. Strikingly, single NAV-HSC successfully maintained its stemness and showed robust multi-lineage engraftments after undergoing the in vitro culture. Mechanistically, NUP98-HOXA10HD fusion and NrasG12D mutation distinctly altered multiple pathways involving the cell cycle, cell division, and DNA replication, and distinctly regulated stemness-related genes including Hoxa9, Prdm16, Hoxb4, Trim27, and Smarcc1 in the context of HSC. Thus, we develop a super-sensitive transgenic model reporting the existence of HSC at the single cell level on culture condition, which could be beneficial for protocol screening of bona fide HSC regeneration from pluripotent stem cells in vitro.

To enhance the anti-wear property of aluminum–silicon (Al–Si) alloy, three processing technologies—chemical etching, mechanical honing and laser finishing—were compared in terms of their effects on anti-wear performance. The treated Al–Si alloy cylinder liner samples were worn against a piston ring by a reciprocating sliding tribotester; the anti-wear performance was represented by the friction coefficient and wear loss; and the wear mechanism was determined by establishing stress contact models. The results showed that the best time for both the chemical etching and mechanical honing treatments was 2 min, and the optimal laser power was 1000 W for the laser finishing treatment. The three processing technologies could all remove the aluminum layer and make the silicon protrude on the surface to avoid the plastic flow of aluminum during the friction process. The laser finishing could not only protrude the silicon particle but also make its edge rounded and smooth, which decreased the stress concentration. Therefore, the Al–Si alloy cylinder liner treated with laser finishing had the best anti-wear performance.

Based on the reservoir characteristics of individual wells, the combined main controlling factor of fracture-vug reservoir and reservoir space synthesized modeling was adopted to establish geological models for the Ordovician reservoirs in the northern slope of the Tazhong palaeouplift and the southern area of the Tabei slope. Geological models for six types of wells were established: (1) cavity + fracture-vug controlled by sequence boundary; (2) cavity + fracture-vug on the top of cavity controlled by fractures; (3) cavity in the surface layer + fracture-vug under the cavity controlled by the sequence boundary and faults; (4) single fracture-vug controlled by the sequence boundary and faults; (5) single vug controlled by deep hydrothermal fluids along faults and fractures; (6) single fracture controlled by faults and fractures. Two types of synthesized geological models were established under the tectonic background of cuesta, namely, platform type slope of the Tazhong area and the gentle slope of the Tabei area. Type 1 and 2 reservoirs are common in the Yijianfang-Yingshan Formation of the HA6-Xinken Region, and type 3 and 5 reservoirs are common in the Yingshan Formation of the ZG8-ZG43 Region. A comprehensive evaluation shows that the reservoir of cavity + fracture-vug on the top of cavity controlled by the sequence boundary is the best, followed by cavity + fracture-vug on the top of cavity controlled by faults. So the areas that meet configuration of cavities and fracture-vugs and single vug controlled by deep hydrothermal fluids along faults and fractures are important targets for exploration and development. Key words: carbonates, fracture-vug reservoir, geological model, main controlling factors, Ordovician, Tazhong-Tabei area

A series of composites of Mn-Fe-Ce/GO-x have been synthesized by a hydrothermal method. Their performance in simultaneously performing the catalytic oxidation of Hg0 and the selective catalytic reduction of nitrogen oxides (NOx) in the same temperature range were investigated. In order to investigate the physicochemical properties and surface reaction, basic tests, including Brunauer-Emmett-Teller (BET), XRD, scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS) were selected. The results indicate that the active components deposited on graphene play an important role in the removal of mercury and NOx, with different valences. Especially, the catalyst of Mn-Fe-Ce/GO-20% possesses an excellent efficiency in the temperature range of 170 to 250 °C. Graphene has a huge specific surface area and good mechanical property; thus, the active components of the Mn-Fe-Ce catalyst can be highly dispersed on the surface of graphene oxide. In addition, the effects of O2, H2O, NO and SO2 on the removal efficiency of Hg0 were examined in flue gas. Furthermore, the regeneration experiments conducted by thermal methods proved to be promising methods.

Buffer solutions were widely used for almost all the investigations concerning N-nitrosodimethylamine (NDMA), a member of powerful mutagenic and carcinogenic compounds which are ubiquitous in the environment. However, whether or how the buffer matrixes influence NDMA formation is still unknown. The effect of buffer solutions on NDMA formation from the nitrosation of dimethylamine (DMA) by nitrite (NaNO2) was investigated at pH 6.4 in four kinds of buffer solutions, that is, Na2HPO4/C6H8O7, Na3(C6H5O7)/C6H8O7, NaH2PO4/NaOH, and NaH2PO4/Na2HPO4. Our observations demonstrate an unexpected inhibitory effect of the buffer solutions on NDMA formation and the phosphate buffer plays a more significant role in inhibiting NDMA formation compared to the citrate buffer. Moreover, the amount of the phosphate in the buffer was also found to greatly impact the formation of NDMA. A further investigation indicates that it is the interaction between NaH2PO4 and reactant NaNO2 rather than DMA that leads to the inhibitory effect of phosphate buffer during the DMA nitrosation reaction. This study expands the understanding of the influence of buffer solution on nitrosamines formation through the nitrosation pathway and further gives a hint for water plants to reduce the formation of nitrosamines.

Original citation: J Clin Invest. 2023;133(14):e160309. https://doi.org/10.1172/JCI160309. Citation for this erratum: J Clin Invest. 2024;134(8):e181331. https://doi.org/10.1172/JCI181331. During the preparation of this manuscript, a text error was introduced during copyediting by [...]

Abstract Background Parapneumonic empyema continues to be a disease of significant morbidity and mortality among children despite recent advances in medical management. To date, only a limited number of studies have assessed the burden of empyema in Asia. Methods We surveyed medical records of four representative large pediatric hospitals in China, Korea, Taiwan and Vietnam using ICD-10 diagnostic codes to identify children Results During the study period, we identified 1,379 children diagnosed with empyema or pleural effusion (China, n = 461; Korea, n = 134; Taiwan, n = 119; Vietnam, n = 665). Diagnoses of pleural effusion (n = 1,074) were 3.5 times more common than of empyema (n = 305), although the relative proportions of empyema and pleural effusion noted in hospital records varied widely between the four sites, most likely because of marked differences in coding practices. Although pleural effusions were reported more often than empyema, children with empyema were more likely to have a cultured pathogen. In addition, we found that median age and gender distribution of children with these conditions were similar across the four countries. Among 1,379 empyema and pleural effusion specimens, 401 (29%) were culture positive. Staphylococcus aureus (n = 126) was the most common organism isolated, followed by Streptococcus pneumoniae (n = 83), Pseudomonas aeruginosa (n = 37) and Klebsiella (n = 35) and Acinetobacter species (n = 34). Conclusion The age and gender distribution of empyema and pleural effusion in children in these countries are similar to the US and Western Europe. S. pneumoniae was the second leading bacterial cause of empyema and pleural effusion among Asian children. The high proportion of culture-negative specimens among patients with pleural effusion or empyema suggests that culture may not be a sufficiently sensitive diagnostic method to determine etiology in the majority of cases. Future prospective studies in different countries would benefit from standardized case definitions and coding practices for empyema. In addition, more sensitive diagnostic methods would improve detection of pathogens and could result in better prevention, treatment and outcomes of this severe disease.