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Background To evaluate the diagnostic value of metagenomic next-generation sequencing (mNGS) of bronchoalveolar lavage fluid (BALF) in immunocompromised patients for the diagnosis of suspected pneumonia in comparison with that of conventional microbiological tests (CMTs). Methods Sixty-nine immunocompromised patients with suspected pneumonia received both CMTs and mNGS of BALF were analyzed retrospectively. The diagnostic value was compared between CMTs and mNGS, using the clinical composite diagnosis as the reference standard. Results Sixty patients were diagnosed of pneumonia including fifty-two patients with identified pathogens and eight patients with probable pathogens. Taking the composite reference standard as a gold standard, 42 pathogens were identified by CMTs including nine bacteria, 17 fungi, 8 virus, 6 Mycobacterium Tuberculosis , and two Legionella and 19(45%) of which were detected by BALF culture. As for mNGS, it identified 76 pathogens including 20 bacteria, 31 fungi, 14 virus, 5 Mycobacterium Tuberculosis , four Legionella and two Chlamydia psittaci . The overall detection rate of mNGS for pathogens were higher than that of CMTs. However, a comparable diagnostic accuracy of mNGS and CMTs were found for bacterial and viral infections. mNGS exhibited a higher diagnostic accuracy for fungal detection than CMTs (78% vs. 57%, P  < 0.05), which mainly because of the high sensitivity of mNGS in patients with Pneumocystis jirovecii pneumonia (PJP) (100% vs. 28%, P  < 0.05). Nineteen patients were identified as pulmonary co-infection, mNGS test showed a higher detection rate and broader spectrum for pathogen detection than that of CMTs in co-infection. Moreover, Pneumocystis jirovecii was the most common pathogen in co-infection and mNGS have identified much more co-pathogens of PJP than CMTs. Conclusions mNGS of BALF improved the microbial detection rate of pathogens and exhibited remarkable advantages in detecting PJP and identifying co-infection in immunocompromised patients.

Photonic materials with positionally ordered structure can interact strongly with light to produce brilliant structural colors. Here, we found that the nonperiodic nematic liquid crystals of nanoplates can also display structural color with only significant orientational order. Owing to the loose stacking of the nematic nanodiscs, such colloidal dispersion is able to reflect a broad-spectrum wavelength, of which the reflection color can be further enhanced by adding carbon nanoparticles to reduce background scattering. Upon the addition of electrolytes, such vivid colors of nematic dispersion can be fine-tuned via electrostatic forces. Furthermore, we took advantage of the fluidity of the nematic structure to create a variety of colorful arts. It was expected that the concept of implanting nematic features in photonic structure of lyotropic nanoparticles may open opportunities for developing advanced photonic materials for display, sensing, and art applications.

Elucidating the mechanisms that influence the assembly and maintenance of communities is a crucial objective in ecological research. However, the mechanisms underlying the maintenance of macroinvertebrate community structure in large rivers on the Tibetan Plateau are still not well understood. To this end, we systematically investigated the spatial distribution characteristics of community diversity and its maintenance mechanisms, focusing on the upper Jinsha River as our study region. During the period from November to December 2022, we collected a total of 126 macroinvertebrate species, representing 5 phyla, 7 classes, 14 orders, 53 families, and 96 genera. Our findings revealed notable variations in species composition among macroinvertebrate communities inhabiting the mainstem and its tributaries. Macroinvertebrate densities, biomass, and species richness were significantly higher in tributaries compared to the mainstem. Additionally, there were significant differences in the Margalef richness index, Pielou evenness index, Shannon diversity index, functional richness, and functional divergence when comparing the mainstem and tributary streams, whereas phylogenetic diversity showed no significant variations. Redundancy analysis demonstrated that the structure of macroinvertebrate communities was notably influenced by a combination of environmental and spatial variables, although the key factors varied among different water bodies. Furthermore, variance partitioning analysis indicated that deterministic processes predominantly shaped macroinvertebrate community assembly, while stochastic processes had a secondary influence. These findings enhance our understanding of macroinvertebrate community dynamics in high‐altitude river systems and provide a scientific basis for the conservation of riverine ecosystems and aquatic biodiversity in the upper Jinsha River. Macroinvertebrate community structure differed significantly among water bodies. Species and functional diversity are higher in tributaries than in mainstems, whereas phylogenetic diversity shows no significant spatial differences. The macroinvertebrate community in the upper Jinsha River are mainly deterministic processes.

Warping and dross formation are the main defects of an overhang structure formed by laser powder bed fusion. In order to study these defects, a seven−shaped overhang structure with different lengths and heights of the overhang was printed. The influence of the temperature and stress field on the overhang structure was investigated using a 3D finite element (FE) model. The results of the simulation showed that the molten pool in the powder support zone was much larger than the molten pool in the solid support zone. The molten pool sank due to the actions of gravity and the capillary force. This led to the powder melting, which then formed a droplet−like dross formation on the lower surface. The temperature difference between the regions led to a large residual stress. When the residual stress exceeded the material strength, warping deformation occurred in the top area, affecting the subsequent powder−laying process. The warping zone was remelted when the next layer was processed. As the number of forming layers increased, the thermal conductivity and stiffness increased continuously, and the deformation of the top area gradually decreased. The experiment results showed that the longer the overhanging length was, the more serious the warpage was. When the overhanging length was below 3 mm, the warping of the top area continued to decrease to zero as the building process proceeded. Meanwhile, the dross formation appeared at the bottom of the overhanging area in all experimental groups. Studying the process of warping and dross formation was helpful to understand the defect change process in the manufacturing process of an overhang structure.

Understanding long-term precipitation changes in Southeast Asia (SEA) is important because the region is highly vulnerable to precipitation-related disasters. This study examines typhoon and non-typhoon heavy precipitation over SEA during 1960–2024 using a typhoon track dataset and three high-resolution precipitation products. Results show a significant decrease in typhoon-precipitation contribution to total precipitation across the entire SEA, both in its continental and maritime regions, especially during the boreal summer half-year. This trend persists under heavy precipitation conditions (95th and 99th percentiles). In contrast, based on tracking results, non-typhoon heavy precipitation shows increases in precipitation area but decreases in lifespan intensity, yielding more total precipitation per event. Our findings indicate a shifting hazard regime: a decrease in typhoon-related rainfall is being offset by a spatial expansion of non-typhoon heavy precipitation, introducing a new regional risk. The findings provide critical insights into the change of regional precipitation patterns and have implications for disaster management and adaptation in SEA.

All inorganic perovskite nanocrystals (AIPNCs) have attracted tremendous research interest due to their fascinating properties in the field of photoelectron. Conventional synthesis of AIPNCs is usually conducted by using batch reactions under gas protection at high temperatures. Herein, an automated microreactor platform consisting of flow-focusing microfluidics is firstly applied to synthesize AIPNCs without gas protection at room temperature. The nucleation and growth is based on the ultrafast mixing and phase separation in low-toxicity solvent. The AIPNCs formed in the microreactor have good crystallinity and narrow size distribution. Meanwhile, the flow-focusing microfluidics also can be used to encapsulate AIPNCs into templated microspheres to improve their stability against temperature, light and water. Furthermore, the as-constructed AIPNC spheres exhibiting linear temperature response represent their promising microthermometer application. It is envisioned that the microfluidic technique provides another alternative to synthesize Ni2+-doped, Ce3+-doped, Yb3+-doped, Bi3+-substituted AIPNCs or organic–inorganic hybrid perovskite nanocrystals and to fabricate templated AIPNC materials and devices.

Background Habenaria , a genus in the family Orchidaceae, are the nearly cosmopolitan orchids, and most species have significant medicinal and ornamental values. Despite the morphological and molecular data that have been studied in recent years, the phylogenetic relationship is still unclear. Results We sequenced, assembled, and annotated the chloroplast (cp) genomes of two species ( Habenaria aitchisonii Rchb.f. and Habenaria tibetica Schltr.ex Limpricht) of Habenaria grown on the Qinghai-Tibetan Plateau (QTP), and compared them with seven previously published cp genomes which may aid in the genomic profiling of these species. The two genomes ranged from 155,259–155,269 bp in length and both included 132 genes, encoding 86 proteins, 38 tRNAs and 8 rRNAs. In the cp genomes, the tandem repeats (797), SSRs (2195) and diverse loci (3214) were identified. Comparative analyses of codon usage, amino frequency, microsatellite, oligo repeats and transition and transversion substitutions revealed similarities between the species. Moreover, we identified 16 highly polymorphic regions with a nucleotide diversity above 0.02, which may be suitable for robust authentic barcoding and inferring in the phylogeny of Habenaria species. Among the polymorphic regions, positive selection was significantly exerted on several genes, such as cemA , petA , and ycf1 . This finding may suggest an important adaptation strategy for the two Habenaria species on the QTP. The phylogenetic relationship revealed that H. aitchisonii and H. tibetica were more closely related to each other than to the other species, and the other seven species were clustered in three groups. In addition, the estimated divergence time suggested that the two species separated from the others approximately 0.39 Mya in the Neogene period. Our findings also suggest that Habenaria can be divided into different sections. Conclusions The results of this study enriched the genomics resources of Habenaria , and SSR marker may aid in the conservation management of two endangered species.

The spatial–temporal patterns of fish assemblages in lotic systems can provide useful information in developing effective conservation measures. This study aimed to explore the spatial and seasonal changes in fish assemblages and their association with environmental factors in mountain streams of the Ren River, southwest China. Field investigations were conducted at 18 sites during the rainy and dry seasons in 2017. A total of 1,330 individuals, belonging to three orders, eight families, 19 genera, and 21 species, were collected. Analysis of similarities (ANOSIM) showed that the structure of fish assemblages varied significantly at the spatial scale, but not at the seasonal scale. In low‐order sites, fish assemblages were mainly dominated by cold‐water and rheophilic species (e.g., Rhynchocypris oxycephalus, Scaphesthes macrolepis, Metahomaloptera omeiensis, and Gnathopogon herzensteini), while those in high‐order sites were predominated by warm‐water and eurytopic or stagnophilic species (e.g., Squalidus argentatus, Hemiculter leucisculus, and Zacco platypus). Canonical correspondence analysis (CCA) showed that the fish assemblages were structured by a combination of large‐scale landscape factors (e.g., altitude and C‐link) and small‐scale habitat features (e.g., channel width, water temperature, and depth). Among these factors, landscape had the greatest influence on fish assemblages, while local habitat variables were less important or were only significant in certain seasons. This study demonstrated how fish assemblages changed at different spatial and temporal scales in this mountain river. Furthermore, environmental factors that contributed most to the observed spatial–temporal patterns of fish assemblage structure were identified. These results provide useful information in understanding the mechanisms structuring fish assemblages and making effective protection measures.

Focusing on the phenomenon of the crack on the autoclave flange, a three-dimensional model of the autoclave was established based on the Ansys Workbench platform. A new finite element analysis flow for optimizing the design of autoclave teeth was established using the Fluent, Static Structure, and Direct Optimization modules. The paper analyzed and discussed the maximum stress and minimum fatigue life at the corresponding position. The variation trend of stress and fatigue life at the corresponding position after fillet optimization was also discussed. The results showed that the equivalent stress of autoclave teeth without fillet optimization reached the maximum under different fillet sizes. The equivalent stress and fatigue life of the autoclave tooth were the same as the rounded corner size obtained by the optimization design. The optimal global solution could be obtained through the optimization design process.

Copper-infiltrated sintered steel is a prominent area of research in powder metallurgy, with a particular focus on enhancing impact toughness. In this study, sintered steels with varying pore structures were prepared using iron powders and infiltrated with copper to investigate their impact toughness. The results indicate a significant improvement in the impact toughness of the sintered steels with concentrated iron particle sizes. The density of the samples increased from 6.85 g cm −3 to 7.55 g cm −3 through copper infiltration. The large copper-phase sample with the particle size of 150 μ m exhibits an impact toughness as high as 41.09 J cm −2 , and its fracture morphology mainly shows transgranular fractures of large iron particles. It is 1.5 times that of the sample made from commercial iron powders which measured 27.46 J cm −2 . This enhancement is primarily attributed to the precipitation of γ -Fe within the large copper phase, thereby enhancing the copper phase and transferring the load into large iron particles. A brief mechanism of γ -Fe precipitation in the large copper-phase has been provided.