Gut fungi of black-necked cranes (Grus nigricollis) respond to dietary changes during wintering.

BACKGROUND: Migratory birds exhibit heterogeneity in foraging strategies during wintering to cope with environmental and migratory pressures, and gut bacteria respond to changes in host diet. However, less is known about the dynamics of diet and gut fungi during the wintering period in black-necked cranes (Grus nigricollis). RESULTS: In this work, we performed amplicon sequencing of the trnL-P6 loop and ITS1 regions to characterize the dietary composition and gut fungal composition of black-necked cranes during wintering. Results indicated that during the wintering period, the plant-based diet of black-necked cranes mainly consisted of families Poaceae, Solanaceae, and Polygonaceae. Among them, the abundance of Solanaceae, Polygonaceae, Fabaceae, and Caryophyllaceae was significantly higher in the late wintering period, which also led to a more even consumption of various food types by black-necked cranes during this period. The diversity of gut fungal communities and the abundance of core fungi were more conserved during the wintering period, primarily dominated by Ascomycota and Basidiomycota. LEfSe analysis (P < 0.05, LDA > 2) found that Pyxidiophora, Pseudopeziza, Sporormiella, Geotrichum, and Papiliotrema were significantly enriched in early winter, Ramularia and Dendryphion were significantly enriched in mid-winter, Barnettozyma was significantly abundant in late winter, and Pleuroascus was significantly abundant in late winter. Finally, mantel test revealed a significant correlation between winter diet and gut fungal. CONCLUSIONS: This study revealed the dynamic changes in the food composition and gut fungal community of black-necked cranes during wintering in Dashanbao. In the late wintering period, their response to environmental and migratory pressures was to broaden their diet, increase the intake of non-preferred foods, and promote a more balanced consumption ratio of various foods. Balanced food composition played an important role in stabilizing the structure of the gut fungal community. While gut fungal effectively enhanced the host's food utilization rate, they may also faced potential risks of introducing pathogenic fungi. Additionally, we recongnized the limitations of fecal testing in studying the composition of animal gut fungal, as it cannot effectively distinguished between fungal taxa from food or soil inadvertently ingested and intestines. Future research on functions such as cultivation and metagenomics may further elucidate the role of fungi in the gut ecosystem.

Convergent evolution toward a slow pace of life predisposes insular endotherms to anthropogenic extinctions.

Island vertebrates have evolved a number of morphological, physiological, and life history characteristics that set them apart from their mainland relatives. However, to date, the evolution of metabolism and its impact on the vulnerability to extinction of insular vertebrates remains poorly understood. This study used metabolic data from 2813 species of tetrapod vertebrates, including 695 ectothermic and 2118 endothermic species, to reveal that island mammals and birds evolved convergent metabolic strategies toward a slow pace of life. Insularity was associated with shifts toward slower metabolic rates and greater generation lengths in endotherms, while insularity just drove the evolution of longer generation lengths in ectotherms. Notably, a slow pace of life has exacerbated the extinction of insular endemic species in the face of anthropogenic threats. These findings have important implications for understanding physiological adaptations associated with the island syndrome and formulating conservation strategies across taxonomic groups with different metabolic modes.

Ultrafast dynamics of exciton-polariton fluids at non-zero momenta.

In this study, we have explored the ultrafast formation and decay dynamics of exciton-polariton fluids at non-zero momenta, non-resonantly excited by a small-spot femtosecond pump pulse in a ZnO microcavity. Using the femtosecond angle-resolved spectroscopic imaging technique, multidimensional dynamics in both the energy and momentum degrees of freedom have been obtained. Two distinct regions with different decay rate in the energy dimension and various decay-channels in the momentum dimension can be well-resolved. Theoretical simulations based on the generalized Gross-Pitaevskii equation can reach a qualitative agreement with the experimental observations, demonstrating the significance of the initial potential barrier induced by the pump pulse during the decay process. The finding of our study can provide additional insights into the fundamental understanding of exciton-polariton condensates, enabling further advancements for controlling the fluids and practical applications.

Metabarcoding of protozoa and helminth in black-necked cranes: a high prevalence of parasites and free-living amoebae.

Parasites and free-living amoebae (FLA) are common pathogens that pose threats to wildlife and humans. The black-necked crane (Grus nigricollis) is a near-threatened species and there is a shortage of research on its parasite diversity. Our study aimed to use noninvasive methods to detect intestinal parasites and pathogenic FLA in G. nigricollis using high-throughput sequencing (HTS) based on the 18S rDNA V9 region. A total of 38 fresh fecal samples were collected in Dashanbao, China, during the overwintering period (early-, middle I-, middle II-, and late-winter). Based on the 18S data, eight genera of parasites were identified, including three protozoan parasites: Eimeria sp. (92.1%) was the dominant parasite, followed by Tetratrichomonas sp. (36.8%) and Theileria sp. (2.6%). Five genera of helminths were found: Echinostoma sp. (100%), Posthodiplostomum sp. (50.0%), Euryhelmis sp. (26.3%), Eucoleus sp. (50.0%), and Halomonhystera sp. (2.6%). Additionally, eight genera of FLA were detected, including the known pathogens Acanthamoeba spp. (n = 13) and Allovahlkampfia spp. (n = 3). Specific PCRs were used to further identify the species of some parasites and FLA. Furthermore, the 18S data indicated significant changes in the relative abundance and genus diversity of the protozoan parasites and FLA among the four periods. These results underscore the importance of long-term monitoring of pathogens in black-necked cranes to protect this near-endangered species.

Title: Métabarcoding des protozoaires et des helminthes chez les grues à cou noir : forte prévalence de parasites et d'amibes libres. Abstract: Les parasites et les amibes libres sont des agents pathogènes courants qui constituent une menace pour la faune et les humains. La grue à cou noir (Grus nigricollis) est une espèce quasi menacée et les recherches sur sa diversité parasitaire sont insuffisantes. Notre étude visait à utiliser des méthodes non invasives pour détecter les parasites intestinaux et les amibes libres pathogènes chez G. nigricollis en utilisant le séquençage à haut débit basé sur la région V9 de l'ADNr 18S. Au total, 38 échantillons de matières fécales fraîches ont été collectés à Dashanbao, en Chine, au cours de la période d'hivernage (début, milieu I, milieu II et fin de l'hiver). Sur la base des données 18S, huit genres de parasites ont été identifiés, dont trois parasites protozoaires : Eimeria sp. (92,1 %) était le parasite dominant, suivi de Tetratrichomonas sp. (36,8 %) et Theileria sp. (2,6 %). Cinq genres d'helminthes ont été trouvés : Echinostoma sp. (100 %), Posthodiplostomum sp. (50,0 %), Euryhelmis sp. (26,3 %), Eucoleus sp. (50,0 %) et Halomonhystera sp. (2,6 %). De plus, huit genres d'amibes libres ont été détectés, y compris les agents pathogènes connus Acanthamoeba spp. (n = 13) et Allovahlkampfia spp. (n = 3). Des PCR spécifiques ont été utilisées pour identifier davantage les espèces de certains parasites et amibes libres. En outre, les données 18S ont indiqué des changements significatifs dans l'abondance relative et la diversité des genres des parasites protozoaires et des amibes au cours des quatre périodes. Ces résultats soulignent l'importance de la surveillance à long terme des agents pathogènes chez les grues à cou noir pour protéger cette espèce quasi menacée.

Epidemiological investigation of Entamoeba in wild rhesus macaques in China: A novel ribosomal lineage and genetic differentiation of Entamoeba nuttalli.

Wild rhesus macaques are a potential source of zoonotic parasites for humans, and Entamoeba spp. are common intestinal parasites. To investigate the prevalence of Entamoeba in wild rhesus macaques in China and explore the genetic differentiation of the potentially pathogenic species Entamoeba nuttalli, a total of 276 fecal samples from five populations at high altitudes (HAG, 2,800-4,100 m above sea level) and four populations at low altitudes (LAG, 5-1,000 m above sea level) were collected. PCR methods based on the ssrRNA gene were used to detect Entamoeba infection. Genotyping of E. nuttalli was performed based on six tRNA-linked short tandem repeat (STR) loci for further genetic analyses. The results revealed that Entamoeba infection (69.2%) was common in wild rhesus macaques in China, especially in LAG which had a significantly higher prevalence rate than that in HAG (P < 0.001). Three zoonotic species were identified: Entamoeba chattoni (60.9%) was the most prevalent species and distributed in all the populations, followed by Entamoeba coli (33.3%) and Entamoeba nuttalli (17.4%). In addition, a novel Entamoeba ribosomal lineage named RL13 (22.8%) was identified, and phylogenetic analysis revealed a close genetic relationship between RL13 and Entamoeba. hartmanni. Genotyping of E. nuttalli obtained 24 genotypes from five populations and further analysis showed E. nuttalli had a high degree of genetic differentiation (FST > 0.25, Nm < 1) between the host populations. The result of analysis of molecular variance (AMOVA) revealed that observed genetic differences mainly originate from differences among populations (FST = 0.91). Meanwhile, the phylogenetic tree showed that these genotypes of E. nuttalli were clustered according to geographical populations, indicating a significant phylogeographic distribution pattern. Considering the potential pathogenicity of E. nuttalli, attention should be paid to its risk of zoonotic transmission.

Coevolution between heat and cold tolerance in endotherms.

Whether the heat and cold tolerance of endotherms evolve independently or correlatively remains unresolved. Both physiological trade-offs and natural selection can contribute to a coevolutionary pattern of heat and cold tolerance in endotherms. Using a published database, we tested the correlation between upper and lower thermal limits across endothermic species with multi-response generalized linear mixed models incorporating phylogenies. We found a positive correlation between upper and lower thermal limits, which suggested a coevolutionary pattern of heat and cold tolerance. Specifically, this relationship between heat and cold tolerance is phylogenetically constrained for tropical endotherms but not for temperate endotherms. The correlated evolution between heat and cold tolerance may have a significant influence on endotherms' evolution and ecology and needs to be further investigated.

Reference gene catalog and metagenome-assembled genomes from the gut microbiome reveal the microbial composition, antibiotic resistome, and adaptability of a lignocellulose diet in the giant panda.

The giant panda, a strict herbivore that feeds on bamboo, still retains a typical carnivorous digestive system. Reference catalogs of microbial genes and genomes are lacking, largely limiting the antibiotic resistome and functional exploration of the giant panda gut microbiome. Here, we integrated 177 fecal metagenomes of captive and wild giant pandas to construct a giant panda integrated gene catalog (GPIGC) comprised of approximately 4.5 million non-redundant genes and reconstruct 393 metagenome-assembled genomes (MAGs). Taxonomic and functional characterization of genes revealed that the captivity of the giant panda significantly changed the core microbial composition and the distribution of microbial genes. Higher abundance and prevalence of antibiotic resistance genes (ARGs) were detected in the guts of captive giant pandas, and ARG distribution was influenced by geography, for both captive and wild individuals. Escherichia, as the prevalent genus in the guts of captive giant pandas, was the main carrier of ARGs, meaning there is a high risk of ARG transmission by Escherichia. We also found that multiple mcr gene variants, conferring plasmid-mediated mobile colistin resistance, were widespread in the guts of captive and wild giant pandas. There were low proportions of carbohydrate-active enzyme (CAZyme) genes in GPIGC and MAGs compared with several omnivorous and herbivorous mammals. Many members of Clostridium MAGs were significantly enriched in the guts of adult, old and wild giant pandas. The genomes of isolates and MAGs of Clostridiaceae harbored key genes or enzymes in complete pathways for degrading lignocellulose and producing short-chain fatty acids (SCFAs), indicating the potential of these bacteria to utilize the low-nutrient bamboo diet. Overall, our data presented an exhaustive reference gene catalog and MAGs in giant panda gut and provided a comprehensive understanding of the antibiotic resistome and microbial adaptability for a high-lignocellulose diet.

Energy deposition in a telescopic laser filament for the control of fuel ignition.

The efficiency of energy coupled to plasma during femtosecond (fs) laser filamentation plays a decisive role in a variety of filament applications such as remote fabrication and spectroscopy. However, the energy deposition characterization in the fs laser filament formed by a telescope, which provides an efficient way to extend the filament distance, has not yet been revealed. In the present study, we show that when the distance between the two lenses in a telescope changes, i.e., the effective focal length changes, there exists an optimal plateau energy deposition region in which the energy deposited into the filament per unit length called the average lineic energy deposition (ALED) remains at high levels, exhibiting a remarkable difference from the monotonic change in a single-lens focusing system. As a proof of principle, we examined the influence of the energy deposition on the ignition of a lean methane/air mixture, and found that the use of the telescope can efficiently extend the ignition distance when compared with a single-lens focusing system under the same incident laser energy condition. Our results may help understand the energy deposition behaviors in a variety of telescopic filaments and provide more options to manipulating laser ignition at a desired distance.

Air-laser-based coherent Raman spectroscopy of atmospheric molecules in a filamentary plasma grating.

Coherent Raman spectroscopy (CRS) with air-laser-based hybrid femtosecond/picosecond (fs/ps) pulses has shown promising potential for remote detection and surveillance of atmospheric species with high temporal and frequency resolution. Here, to enhance the sensitivity and extend the detection distance, we generate the CRS spectra of air molecules in situ in a filamentary plasma grating, and show that the grating can efficiently enhance the intensities of the coherent vibrational Raman lines of N2, O2, and N2 + by 2-3 orders of magnitude at an extended distance. By examining the intensities of the Raman lines, fs-pulsed supercontinuum, and ps-pulsed air laser produced under different grating conditions, we reveal that the optimization of the Raman lines is achieved by the dynamic balance between the supercontinuum-induced vibrational coherence and air-laser-induced polarization of the air species.

Diet and feeding behavior of a group of high-altitude rhesus macaques: high adaptation to food shortages and seasonal fluctuations.

Diet and feeding behavior data are crucial to a deep understanding of the behavioral response and adaptation of primates to a high-altitude environment. From August 2019 to June 2021, we collected data on the feeding behavior of a high-altitude rhesus macaque Macaca mulatta group from Yajiang County, Western Sichuan Plateau, which has an altitude of over 3,500 m. The results showed that feeding (33.0 ± 1.8%) and moving (28.3 ± 2.6%) were the dominant behavior of rhesus macaques. Macaques ate 193 food items, comprising 11 food categories from 90 species. Our study found that plant roots (30.9 ± 30.1%) and young leaves (28.0 ± 33.1%) were the main foods eaten by macaques. The preferred foods of rhesus macaques were young leaves, fruits, and seeds, and the consumption of these items was positively correlated with its food availability. When the availability of preferred foods was low, macaques took plant roots, barks, and fallen leaves as fallback foods. In particular, roots were a dominant food item in winter, and this way of feeding became a key survival strategy. Our results suggest that, facing the relative scarcity and strong seasonal fluctuations of food resources in high-altitude habitat, macaques adopt active foraging strategies, relying on a variety of food species and adjusting flexibly their food choices based on food availability, which may help to maximize the energy efficiency of high-altitude macaques.

Gut microbiota enhance energy accumulation of black-necked crane to cope with impending migration.

Less is known about the role of gut microbiota in overwintering environmental adaptation in migratory birds. Here, we performed metagenomic sequencing on fresh fecal samples (n = 24) collected during 4 periods of overwintering (Dec: early; Jan: middle I; Feb: middle II; Mar: late) to characterize gut microbial taxonomic and functional characteristics of black-necked crane (Grus nigricollis). The results demonstrated no significant change in microbial diversity among overwintering periods. Analysis of compositions of microbiomes with bias correction (ANCOM-BC) determined 15 Proteobacteria species enriched in late overwintering period. Based on previous reports, these species are associated with degradation of chitin, cellulose, and lipids. Meanwhile, fatty acid degradation and betalain biosynthesis pathways are enriched in late overwintering period. Furthermore, metagenomic binning obtained 91 high-quality bins (completeness >70% and contamination <10%), 5 of which enriched in late overwintering period. Carnobacterium maltaromaticum, unknown Enterobacteriaceae, and Yersinia frederiksenii have genes for chitin and cellulose degradation, acetate, and glutamate production. Unknown Enterobacteriaceae and Y. frederiksenii hold genes for synthesis of 10 essential amino acids required by birds, and the latter has genes for γ-aminobutyrate production. C. maltaromaticum has genes for pyridoxal synthesis. These results implied the gut microbiota is adapted to the host diet and may help black-necked cranes in pre-migratory energy accumulation by degrading the complex polysaccharide in their diet, supplying essential amino acids and vitamin pyridoxal, and producing acetate, glutamate, and γ-aminobutyrate that could stimulate host feeding. Additionally, enriched Proteobacteria also encoded more carbohydrate-active enzymes (CAZymes) and antibiotic resistance genes (ARGs) in late overwintering period. KEY POINTS: • Differences in gut microbiota function during overwintering period of black-necked cranes depend mainly on changes in core microbiota abundance • Gut microbiota of black-necked crane adapted to the diet during overwintering period • Gut microbiota could help black-necked cranes to accumulate more energy in the late overwintering period.

Metagenome and metabolome insights into the energy compensation and exogenous toxin degradation of gut microbiota in high-altitude rhesus macaques (Macaca mulatta).

There have been many reports on the genetic mechanism in rhesus macaques (RMs) for environmental adaptation to high altitudes, but the synergistic involvement of gut microbiota in this adaptation remains unclear. Here we performed fecal metagenomic and metabolomic studies on samples from high- and low-altitude populations to assess the synergistic role of gut microbiota in the adaptation of RMs to high-altitude environments. Microbiota taxonomic annotation yielded 7471 microbiota species. There were 37 bacterial species whose abundance was significantly enriched in the high-altitude populations, 16 of which were previously reported to be related to the host's dietary digestion and energy metabolism. Further functional gene enrichment found a stronger potential for gut microbiota to synthesize energy substrate acetyl-CoA using CO2 and energy substrate pyruvate using oxaloacetate, as well as a stronger potential to transform acetyl-CoA to energy substrate acetate in high-altitude populations. Interestingly, there were no apparent differences between low-altitude and high-altitude populations in terms of genes enriched in the main pathways by which the microbiota consumed the three energy substrates, and none of the three energy substrates were detected in the fecal metabolites. These results strongly suggest that gut microbiota plays an important energy compensatory role that helps RMs to adapt to high-altitude environments. Further functional enrichment after metabolite source analysis indicated the abundance of metabolites related to the degradation of exogenous toxins was also significantly higher in high-altitude populations, which suggested a contributory role of gut microbiota to the degradation of exogenous toxins in wild RMs adapted to high-altitude environments.

Diet and high altitude strongly drive convergent adaptation of gut microbiota in wild macaques, humans, and dogs to high altitude environments.

Animal gut microbiota plays an indispensable role in host adaptation to different altitude environments. At present, little is known about the mechanism of animal gut microbiota in host adaptation to high altitude environments. Here, we selected wild macaques, humans, and dogs with different levels of kinship and intimate relationships in high altitude and low altitude environments, and analyzed the response of their gut microbiota to the host diet and altitude environments. Alpha diversity analysis found that at high altitude, the gut microbiota diversity of wild macaques with more complex diet in the wild environments is much higher than that of humans and dogs with simpler diet (p < 0.05), and beta diversity analysis found that the UniFrac distance between humans and dogs was significantly lower than between humans and macaques (p < 0.05), indicating that diet strongly drive the convergence of gut microbiota among species. Meanwhile, alpha diversity analysis found that among three subjects, the gut microbiota diversity of high altitude population is higher than that of low altitude population (ACE index in three species, Shannon index in dog and macaque and Simpson index in dog, p < 0.05), and beta diversity analysis found that the UniFrac distances among the three subjects in the high altitude environments were significantly lower than in the low altitude environments (p < 0.05). Additionally, core shared ASVs analysis found that among three subjects, the number of core microbiota in high altitude environments is higher than in low altitude environments, up to 5.34 times (1,105/207), and the proportion and relative abundance of the core bacteria types in each species were significantly higher in high altitude environments than in low altitude environments (p < 0.05). The results showed that high altitude environments played an important role in driving the convergence of gut microbiota among species. Furthermore, the neutral community model trial found that the gut microbiota of the three subjects was dispersed much more at high altitude than at low altitude, implying that the gut microbiota convergence of animals at high altitudes may be partly due to the microbial transmission between hosts mediated by human activities.

Extensive prevalence and significant genetic differentiation of Blastocystis in high- and low-altitude populations of wild rhesus macaques in China.

BACKGROUND: Blastocystis is a common intestinal protist with a wide range of hosts. Thus far, 38 subtypes have been identified. In recent years, wild animals have been confronted with habitat fragmentation as well as an increasing risk of zoonotic disease transmission due to human disturbance. Only limited data are available on Blastocystis infection and subtype distribution in wild rhesus macaques in China. The aim of the present study was to investigate the prevalence and genetic diversity of Blastocystis in nine wild rhesus macaque populations in China. METHODS: A total of 276 faecal samples were collected from five high-altitude populations (high-altitude group [HAG]; 2800-4100 m a.s.l.) and four low-altitude populations (low-altitude group [LAG]; 5-1000 m a.s.l) of rhesus macaques. PCR-based analysis, using a new primer pair for the amplification of a 1690-bp sequence of the small subunit ribosomal RNA (SSU rRNA) gene, was used for prevalence and genetic diversity analysis. RESULT: Analysis of faecal samples revealed that Blastocystis infection was common in rhesus macaques, with an infection positivity rate of 80.1% (n = 221/276 samples). There was no significant difference (P = 0.121) in positivity rate between the LAG (84.3%) and HAG (76.8%). Overall, 33 haplotypes were obtained and classified into four subtypes (STs), of which three were potentially zoonotic subtypes (ST1, 29.7%; ST2, 16.7%; ST3, 31.9%) and one that was first identified in this study and named ST39 (12.0%). The STs were distributed differently among the rhesus macaque populations, except for ST3, which was found in all populations. Phylogenetic analyses revealed two major divergent clades of ST3 for the HAG and LAG. Genetic diversity analysis showed a high genetic diversity of ST3 (haplotype diversity: 0.846; nucleotide diversity: 0.014) in the rhesus macaques, but a high genetic differentiation (FST > 0.25) and a low gene flow (Nm = 0.09) between the HAG and LAG. CONCLUSION: Our study, which is the first investigation on Blastocystis infection in multiple wild rhesus macaque populations in China, indicates a potential risk of zoonotic transmission of Blastocystis in the study areas. Blastocystis ST3 showed high genetic diversity in wild rhesus macaques and significant genetic differentiation between the HAG and LAG. Our results provide fundamental information on the genetic diversity and prevalence of Blastocystis in wild rhesus macaque populations.

Interfacial Engineering Boosts Highly Reversible Zinc Metal for Aqueous Zinc-Ion Batteries.

Zinc metal is emerging as the promising anode for aqueous Zn-ion batteries. However, corrosion and undesirable Zn dendrite growth limit their practical application in the large-scale energy storage area. Herein, a mountain-valley micro/nanostructure is successfully fabricated on the surface of the Zn anode via a femtosecond-laser filament texturing (FsLFT) technique. Beneficial from the large surface area and spontaneously generated ZnO coating layer, the FsLFT-Zn electrode demonstrates a slow corrosion rate with a current density of 0.62 mA cm-2 and a stable cycle life over 3000 h under 1 mA cm-2, superior to the original Zn anode. Simulation of the electric fields reveals that the enlarged surface area is responsible for the outstanding performance of the FsLFT-Zn electrode. This study not only proposes a novel strategy to suppress dendrite growth toward highly stable AZIBs but also opens a new avenue to solve similar issues in other metal batteries.

Transition from triggered super-radiance to seed amplification in N2 + lasing.

Air lasing induced by laser filamentation opens a new route for research on atmospheric molecular physics and remote sensing. The generation of air lasing is composed of two processes, i.e., building up optical gain of air molecules in femtosecond time scale and emitting coherent radiation in picosecond time scale. Here, we focus on the emission mechanisms of N2 + air lasing and reveal, by examining the intensities and temporal profiles of N2 + lasing at 391 nm generated respectively in a time-varying polarization-modulated and a linearly polarized pump laser field under different nitrogen gas pressures, that the N2 + lasing can emit through either triggered super-radiance or seed amplification. We find that the two pressure-sensitive factors, i.e., the dipole dephasing time T2 and the population inversion density n, determine which of these two mechanisms dominates the N2 + lasing emission process, enabling manipulation of the transition from triggered super-radiance to seed amplification or vice versa. Our findings clarify the emission mechanism of N2 + lasing under different pressures and provide a deeper understanding of N2 + air lasing not only in the establishment of optical gain but also in the lasing emission process.

Black TiO2-Based Dual Photoanodes Boost the Efficiency of Quantum Dot-Sensitized Solar Cells to 11.7.

Quantum dot-sensitized solar cells (QDSSC) have been regarded as one of the most promising candidates for effective utilization of solar energy, but its power conversion efficiency (PCE) is still far from meeting expectations. One of the most important bottlenecks is the limited collection efficiency of photogenerated electrons in the photoanodes. Herein, we design QDSSCs with a dual-photoanode architecture, and assemble the dual photoanodes with black TiO2 nanoparticles (NPs), which were processed by a femtosecond laser in the filamentation regime, and common CdS/CdSe QD sensitizers. A maximum PCE of 11.7% with a short circuit current density of 50.3 mA/cm2 is unambiguously achieved. We reveal both experimentally and theoretically that the enhanced PCE is mainly attributed to the improved light harvesting of black TiO2 due to the black TiO2 shells formed on white TiO2 NPs.

Dexmedetomidine alleviates intestinal barrier dysfunction and inflammatory response in mice via suppressing TLR4/MyD88/NF-κB signaling in an experimental model of ulcerative colitis.

INTRODUCTION: Ulcerative colitis (UC) is a nonspecific intestinal inflammatory disease. Dexmedetomidine (DEX) is a selective alpha 2-adrenergic receptor agonist commonly used for analgesia and sedation in intensive care units. Herein, the role and mechanism of DEX in dextran sulfate sodium (DSS)-induced colitis was explored. MATERIALS AND METHODS: A murine model of DSS-induced colitis was established by adding 3.5% (w/v) DSS in drinking water to C57BL/6J female mice. The severity of colitis was measured by the disease activity index (DAI) score, colon length and body weight of mice. The serum concentration and mRNA levels of inflammatory cytokines in colon tissues were assessed by ELISA and RT-qPCR, respectively. Protein levels of apoptotic markers, tight junction proteins and genes involved in the TLR4/MyD88/NF-κB signaling were quantified utilizing Western blotting. The pathological changes of colon tissues were evaluated by hematoxylin-eosin (HE) staining and histological score. Intestinal permeability in vivo was assessed by fluorescein isothiocyanate (FITC)-dextran (FITC-D) administration. TUNEL assay was used to determine cell apoptosis in the intestinal epithelium. RESULTS: DSS administration resulted in weight loss, shortening of the colon, increased DAI score, histological abnormalities, and increased serum FITC-D levels in mice, all of which were reversed by DEX injection. Moreover, DEX attenuated DSS-triggered inflammatory response, intestinal barrier injury and intestinal epithelial cell apoptosis. Mechanically, DEX inactivated the TLR4/MyD88/NF-κB signaling in the colon tissues. CONCLUSIONS: DEX exerts beneficial effects against the intestinal barrier dysfunction, inflammatory response, and apoptosis of intestinal epithelial cells via inactivation of the TLR4/MyD88/NF-κB signaling in mice with DSS-induced colitis.

Sensing Trace-Level Metal Elements in Water Using Chirped Femtosecond Laser Pulses in the Filamentation Regime.

Femtosecond filament-induced breakdown spectroscopy (FIBS) is an efficient approach in remote and in situ detection of a variety of trace elements, but it was recently discovered that the FIBS of water is strongly dependent on the large-bandgap semiconductor property of water, making the FIBS signals sensitive to laser ionization mechanisms. Here, we show that the sensitivity of the FIBS technique in monitoring metal elements in water can be efficiently improved by using chirped femtosecond laser pulses, but an asymmetric enhancement of the FIBS intensity is observed for the negatively and positively chirped pulses. We attribute the asymmetric enhancement to their different ionization rates of water, in which the energy of the photons participating in the ionization process in the front part of the negatively chirped pulse is higher than that in the positively chirped pulse. By optimizing the pulse chirp, we show that the limit of detection of the FIBS technique for metal elements in water, e.g., aluminum, can reach to the sub-ppm level, which is about one order of magnitude better than that by the transform-limited pulse. We further examine the FIBS spectra of several representative water samples including commercial mineral water, tap water, and lake water taken from two different environmental zones, i.e., a national park and a downtown business district (Changchun, China), from which remarkably different concentrations of Ca, Na, and K elements of these samples are obtained. Our results provide a possibility of using FIBS for direct and fast metal elemental analysis of water in different field environments.

Molecular Epidemiology of Blastocystis in Confined Slow Lorises, Macaques, and Gibbons.

Blastocystis sp. is a common intestinal anaerobic parasite infecting non-human primates and many other animals. This taxon threatens the health of NHPs due to its high genetic diversity, impeding efforts to improve confined management and subsequent conservation practices. This study collected 100 and 154 fecal samples from captive macaques, gibbons, and slow lorises in the summer and winter, respectively. The Blastocystis infection, its gene subtypes, and its zoonotic potential based on small subunit ribosomal RNA (SSU rRNA) were analyzed. The prevalence of Blastocystis in the three primate genera was 57.79% (89/154) in the summer (2021) and 29.00% (29/100) in the winter (2020). Four zoonotic subtypes-ST1, ST2, ST3, and ST4-were identified. ST2 was the most prevalent subtype, suggesting that these animals may serve as reservoirs for pathogens of human Blastocystis infections. The macaques showed a more significant variation in Blastocystis infection between seasons than gibbons and slow lorises. The slow lorises in small cages and enclosure areas were potentially more infected by Blastocystis in the summer, indicating that inappropriate captive management may have detrimental effects on their health.