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1.
Nature ; 620(7976): 994-1000, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37290482

RESUMEN

All-perovskite tandem solar cells promise higher power-conversion efficiency (PCE) than single-junction perovskite solar cells (PSCs) while maintaining a low fabrication cost1-3. However, their performance is still largely constrained by the subpar performance of mixed lead-tin (Pb-Sn) narrow-bandgap (NBG) perovskite subcells, mainly because of a high trap density on the perovskite film surface4-6. Although heterojunctions with intermixed 2D/3D perovskites could reduce surface recombination, this common strategy induces transport losses and thereby limits device fill factors (FFs)7-9. Here we develop an immiscible 3D/3D bilayer perovskite heterojunction (PHJ) with type II band structure at the Pb-Sn perovskite-electron-transport layer (ETL) interface to suppress the interfacial non-radiative recombination and facilitate charge extraction. The bilayer PHJ is formed by depositing a layer of lead-halide wide-bandgap (WBG) perovskite on top of the mixed Pb-Sn NBG perovskite through a hybrid evaporation-solution-processing method. This heterostructure allows us to increase the PCE of Pb-Sn PSCs having a 1.2-µm-thick absorber to 23.8%, together with a high open-circuit voltage (Voc) of 0.873 V and a high FF of 82.6%. We thereby demonstrate a record-high PCE of 28.5% (certified 28.0%) in all-perovskite tandem solar cells. The encapsulated tandem devices retain more than 90% of their initial performance after 600 h of continuous operation under simulated one-sun illumination.

2.
Nature ; 603(7899): 73-78, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35038717

RESUMEN

All-perovskite tandem solar cells hold the promise of surpassing the efficiency limits of single-junction solar cells1-3; however, until now, the best-performing all-perovskite tandem solar cells have exhibited lower certified efficiency than have single-junction perovskite solar cells4,5. A thick mixed Pb-Sn narrow-bandgap subcell is needed to achieve high photocurrent density in tandem solar cells6, yet this is challenging owing to the short carrier diffusion length within Pb-Sn perovskites. Here we develop ammonium-cation-passivated Pb-Sn perovskites with long diffusion lengths, enabling subcells that have an absorber thickness of approximately 1.2 µm. Molecular dynamics simulations indicate that widely used phenethylammonium cations are only partially adsorbed on the surface defective sites at perovskite crystallization temperatures. The passivator adsorption is predicted to be enhanced using 4-trifluoromethyl-phenylammonium (CF3-PA), which exhibits a stronger perovskite surface-passivator interaction than does phenethylammonium. By adding a small amount of CF3-PA into the precursor solution, we increase the carrier diffusion length within Pb-Sn perovskites twofold, to over 5 µm, and increase the efficiency of Pb-Sn perovskite solar cells to over 22%. We report a certified efficiency of 26.4% in all-perovskite tandem solar cells, which exceeds that of the best-performing single-junction perovskite solar cells. Encapsulated tandem devices retain more than 90% of their initial performance after 600 h of operation at the maximum power point under 1 Sun illumination in ambient conditions.

3.
BMC Genomics ; 25(1): 286, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38500030

RESUMEN

BACKGROUND: Encystment is an important survival strategy extensively employed by microbial organisms to survive unfavorable conditions. Single-celled ciliated protists (ciliates) are popular model eukaryotes for studying encystment, whereby these cells degenerate their ciliary structures and develop cyst walls, then reverse the process under more favorable conditions. However, to date, the evolutionary basis and mechanism for encystment in ciliates is largely unknown. With the rapid development of high-throughput sequencing technologies, genome sequencing and comparative genomics of ciliates have become effective methods to provide insights into above questions. RESULTS: Here, we profiled the MAC genome of Pseudourostyla cristata, a model hypotrich ciliate for encystment studies. Like other hypotrich MAC genomes, the P. cristata MAC genome is extremely fragmented with a single gene on most chromosomes, and encodes introns that are generally small and lack a conserved branch point for pre-mRNA splicing. Gene family expansion analyses indicate that multiple gene families involved in the encystment are expanded during the evolution of P. cristata. Furthermore, genomic comparisons with other five representative hypotrichs indicate that gene families of phosphorelay sensor kinase, which play a role in the two-component signal transduction system that is related to encystment, show significant expansion among all six hypotrichs. Additionally, cyst wall-related chitin synthase genes have experienced structural changes that increase them from single-exon to multi-exon genes during evolution. These genomic features potentially promote the encystment in hypotrichs and enhance their ability to survive in adverse environments during evolution. CONCLUSIONS: We systematically investigated the genomic structure of hypotrichs and key evolutionary phenomenon, gene family expansion, for encystment promotion in ciliates. In summary, our results provided insights into the evolutionary mechanism of encystment in ciliates.


Asunto(s)
Cilióforos , Quistes , Humanos , Genómica , Mapeo Cromosómico , Transducción de Señal , Cilióforos/genética
4.
Inorg Chem ; 63(23): 10854-10859, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38781121

RESUMEN

The arrangement of functional groups exerts a crucial role in determining the characteristics of compounds. In this study, we synthesized two novel short-wave ultraviolet (UV) nonlinear optical (NLO) crystals: KBe2(SeO3)2(OH)·H2O and K2Be(SeO3)2. Interestingly, the two compounds show the same SeO3 triangular pyramids and K-O polyhedra. However, the two compounds exhibit distinct beryllium-oxygen anion groups: BeO3(OH) for KBe2(SeO3)2(OH)·H2O and BeO4 for K2Be(SeO3)2. This results in the SeO3 groups within the structure having different orientations, ultimately leading to the two compounds exhibiting completely different optical properties. KBe2(SeO3)2(OH)·H2O displays a large second harmonic generation (SHG) effect equivalent to 2× KH2PO4 (KDP), coupled with a large birefringence of 0.078 at 546 nm. In contrast, the SHG effect and birefringence of K2Be(SeO3)2 are only 0.33× that of KDP and 0.024 at 546 nm, respectively. Structural analyses and theoretical calculations indicate that these pronounced differences in optical properties stem from variations in the arrangement of the SeO3 functional groups. This study not only sheds light on the correlation between crystal structure and optical behavior but also presents a hopeful avenue for the advancement of materials in the short-wave UV spectrum.

5.
Mol Phylogenet Evol ; 189: 107936, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37778530

RESUMEN

The huge variety of species and worldwide distribution of ciliated protists in class Spirotrichea continue to make it one of the most complicated and confused groups in Ciliophora, despite significant research interest in the unique molecular genetics of these organisms. In this study, the morphological and molecular information were integrated, and it is inferred from a new perspective for the evolutionary relationship among Phacodiniidia, Protohypotrichia, Hypotrichia and Euplotia. Our results indicate that Kiitricha and Caryotricha, two members in Protohypotrichia, may represent two parallel branches of evolution; Euplotidae and Aspidiscidae represent the most recently diverged taxa within Euplotida, followed by Certesiidae, Gastrocirrhidae, and Uronychidae. Further, representative morphological characters (e.g. fronto-ventral-transverse cirral anlagen, undulating membranes, marginal cirri and caudal cirri) were stochastically mapped on phylogenies to speculate evolutionary path and morphological characters of the evolutionary transition node groups were assumed.


Asunto(s)
Cilióforos , Filogenia , Cilióforos/genética
6.
Angew Chem Int Ed Engl ; 62(51): e202313374, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-37921234

RESUMEN

Combining wide-band gap (WBG) and narrow-band gap (NBG) perovskites with interconnecting layers (ICLs) to construct monolithic all-perovskite tandem solar cell is an effective way to achieve high power conversion efficiency (PCE). However, optical losses from ICLs need to be further reduced to leverage the full potential of all-perovskite tandem solar cells. Here, metal oxide nanocrystal layers anchored with carbazolyl hole-selective-molecules (CHs), which exhibit much lower optical loss, is employed to replace poly(3,4-ethylenedioxythiophene) polystyrenesulfonate (PEDOT : PSS) as the hole transporting layers (HTLs) in lead-tin (Pb-Sn) perovskite sub-cells and ICLs in all-perovskite tandem solar cells. Optically transparent indium tin oxide nanocrystals (ITO NCs) layers are employed to enhance anchoring of CHs, while a mixture of two CHs is adopted to tune the surface energy-levels of ITO NCs. The optimized mixed Pb-Sn NBG perovskite solar cells demonstrate a high PCE of 23.2 %, with a high short-circuit current density (Jsc ) of 33.5 mA cm-2 . A high PCE of 28.1 % is further obtained in all-perovskite tandem solar cells, with the highest Jsc of 16.7 mA cm-2 to date. Encapsulated tandem solar cells maintain 90 % of their reference point after 500 h of operation at the maximum power point (MPP) under 1-Sun illumination.

7.
Mol Phylogenet Evol ; 169: 107406, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35031457

RESUMEN

The class Karyorelictea, a unique assemblage of ciliates, is a key group in deciphering ciliate evolution history. However, the systematic relationships among members of this class remain poorly understood. Here we newly obtained eight small subunit (SSU) rDNA, 24 large subunit (LSU) rDNA, and 25 ITS1-5.8S-ITS2 sequences (covering 25 species, 10 genera and 4 out of 6 families) to analyze the phylogenetic relationships within Karyorelictea. Our results indicate that: (1) considering its unique morphology and early branching position in the SSU rDNA-based tree, the family Wilbertomorphidae represents a new taxon at order level, hence the new order Wilbertomorphida n. ord. is established; (2) all five families with available molecular information are monophyletic, as expected, and the orders Loxodida and Protostomatida show a closer relationship than with Protoheterotrichida; (3) in Trachelocercidae, the compound circumoral kineties is believed to be a plesiomorphic feature while the single circumoral kinety is synapomorphic; and (4) the freshwater genus Loxodes could be derived from the marine Remanella and both share most morphological features. Taken together, these muti-gene analyses provide further insights into the phylogeny of the diverse clades in Karyorelictea.


Asunto(s)
Cilióforos , Cilióforos/genética , ADN Protozoario/genética , ADN Ribosómico/genética , Humanos , Filogenia , Análisis de Secuencia de ADN
8.
J Eukaryot Microbiol ; 68(1): e12832, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33141463

RESUMEN

The morphology, morphogenesis and molecular phylogeny of Parabistichella dieckmanni (Foissner, 1998) Foissner, 2016, isolated from north China, were investigated. The Chinese population was characterized as having five to seven frontal cirri in corona, four to seven buccal cirri arranged in a row, two to four short frontal rows and two long frontoventral rows, three to seven transverse cirri, four macronuclear nodules, three dorsal kineties following a Gonostomum-pattern, and caudal cirri absent. Morphogenetic research reveals that the main characteristics during binary fission are as follows: (1) the long left frontoventral row is formed by two or three anlagen; (2) the posterior part of the parental adoral zone of membranelles is renewed, and the oral primordium of the opisthe is formed intrakinetally; (3) FVT-anlagen I to VI (or V, VII) produce each a frontal cirrus to form the frontal corona; (4) development of dorsal kineties follows the Gonostomum-pattern. Phylogenetic analyses showed that P. dieckmanni does not group with other Parabistichella species. Therefore, the genus Parabistichella is polyphyletic. Additionally, Parabistichella variabilis n. comb. (basionym: Bistichella variabilis He & Xu, 2011) and Parabistichella cheni n. nom. (basionym: Parabistichella variabilis Jiang et al., 2013) were suggested.


Asunto(s)
Hypotrichida/citología , Hypotrichida/crecimiento & desarrollo , China , ADN Protozoario/análisis , ADN Ribosómico/análisis , Hypotrichida/clasificación , Morfogénesis , Filogenia , Suelo/parasitología
9.
Anal Chem ; 92(12): 8254-8261, 2020 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-32388978

RESUMEN

Techniques for the qualitative and quantitative detection of H2S in vivo have attracted considerable attention due to the key role of H2S in various physiological and pathological processes. However, in vivo detection strategies for H2S are mainly based on fluorescence imaging, which is limited by its poor tissue penetration. Moreover, the limitations of single-mode probes are amplified in complex physiological environments. Herein, a core-shell Fe3O4@Cu2O nanoparticle was constructed as a magnetic-photoacoustic dual-mode probe for H2S detection in vitro and in vivo based on the in situ response of Cu2O to endogenous H2S in colon tumors. This probe is expected to greatly improve the accuracy of H2S detection in vivo because it employs two detection methods with complementary advantages. The new probe was experimentally applied to the in vivo and in vitro visualization of H2S in mice with colorectal cancer, validating the in situ reaction-activated dual-detection method. This work establishes a simple and efficient dual-mode imaging method based on a novel trigger mechanism. The findings provide a new strategy for colon cancer detection based on the in situ reactions at tumor sites.


Asunto(s)
Neoplasias Colorrectales/diagnóstico por imagen , Sulfuro de Hidrógeno/análisis , Técnicas Fotoacústicas , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cobre/química , Cobre/farmacología , Compuestos Férricos/química , Compuestos Férricos/farmacología , Células HCT116 , Humanos , Fenómenos Magnéticos , Imagen por Resonancia Magnética , Ratones , Ratones Desnudos , Nanopartículas/química , Neoplasias Experimentales/diagnóstico por imagen , Tamaño de la Partícula , Propiedades de Superficie
10.
J Eukaryot Microbiol ; 66(3): 413-423, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30099801

RESUMEN

In recent years, Tetrahymena species have been used as model organisms for research in a wide range of fields, highlighting the need for a fuller understanding of the taxonomy of this group. It is in this context that this paper uses living observation and silver staining methods to investigate the morphology and infraciliature of one Tetrahymena species, T. setosa (Schewiakoff 1892 Verh. Naturh. Med. Ver. Heidelb., 4:544) McCoy (1975) Acta Protozool., 14:253; the senior subjective synonym of T. setifera Holz and Corliss (1956) J. Protozool., 3:112; isolated from a freshwater pond in Harbin, north-eastern China. This organism can be distinguished from other described Tetrahymena species mainly by its single caudal cilium, which is about twice the length of the somatic ciliature. While the Harbin isolate appears similar to the population described by Holz and Corliss (1956) J. Protozool., 3:112, an improved diagnosis for T. setosa is given based on the previous descriptions and the Harbin population. In summary, this species can be recognized mainly by the combination of the following characters: body in vivo approximately 40 µm × 25 µm, 21-26 somatic kineties, one to four contractile vacuole pores associated with meridians 6-11 and a single caudal cilium. The small subunit ribosomal (SSU) rRNA gene and the cox1 gene sequences of Harbin population are also characterized in order to corroborate that the isolated species branches in phylogenetic trees as a T. setosa species. The phylogenetic analysis also indicated that sequences of populations of Tetrahymena species should be published with detailed morphological identifications.


Asunto(s)
Filogenia , Tetrahymena/clasificación , China , Complejo IV de Transporte de Electrones/análisis , Proteínas Protozoarias/análisis , ARN Protozoario/análisis , Tetrahymena/citología , Tetrahymena/genética
11.
Proc Biol Sci ; 284(1859)2017 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-28747472

RESUMEN

Small subunit ribosomal DNA (SSU rDNA) is widely used for phylogenetic inference, barcoding and other taxonomy-based analyses. Recent studies indicate that SSU rDNA of ciliates may have a high level of sequence variation within a single cell, which impacts the interpretation of rDNA-based surveys. However, sequence variation can come from a variety of sources including experimental errors, especially the mutations generated by DNA polymerase in PCR. In the present study, we explore the impact of four DNA polymerases on sequence variation and find that low-fidelity polymerases exaggerate the estimates of single-cell sequence variation. Therefore, using a polymerase with high fidelity is essential for surveys of sequence variation. Another source of variation results from errors during amplification of SSU rDNA within the polyploidy somatic macronuclei of ciliates. To investigate further the impact of SSU rDNA copy number variation, we use a high-fidelity polymerase to examine the intra-individual SSU rDNA polymorphism in ciliates with varying levels of macronuclear amplification: Halteria grandinella, Blepharisma americanum and Strombidium stylifer We estimate the rDNA copy numbers of these three species by single-cell quantitative PCR. The results indicate that: (i) sequence variation of SSU rDNA within a single cell is authentic in ciliates, but the level of intra-individual SSU rDNA polymorphism varies greatly among species; (ii) rDNA copy numbers vary greatly among species, even those within the same class; (iii) the average rDNA copy number of Halteria grandinella is about 567 893 (s.d. = 165 481), which is the highest record of rDNA copy number in ciliates to date; and (iv) based on our data and the records from previous studies, it is not always true in ciliates that rDNA copy numbers are positively correlated with cell or genome size.


Asunto(s)
Cilióforos/genética , Variaciones en el Número de Copia de ADN , ADN Ribosómico/genética , Filogenia , Error Científico Experimental , Análisis de la Célula Individual
12.
Mol Phylogenet Evol ; 112: 96-106, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28438700

RESUMEN

Most ciliate phylogenetic analyses have largely relied on the nuclear small subunit ribosome DNA (nSSU-rDNA) locus. However, single locus or multi-loci from the same genome or chromosome may not be sufficient enough to elucidate phylogenetic relationships among ciliate taxa. Therefore, in addition to nSSU-rDNA, the mitochondrial small subunit ribosome DNA (mtSSU-rDNA) was applied in this study. We expanded the taxon sampling especially within the class Phyllopharyngea. Phylogenetic analyses based on nSSU-rDNA and mtSSU-rDNA, independently, as well as concatenated were performed and revealed the following: (1) mtSSU-rDNA is more variable than nSSU-rDNA, and is better at elucidating relationships at lower levels, e.g. intra-/inter-specific or generic relationships; (2) the validity of the two genera Mirodysteria and Spirodysteria is challenged based on their similar morphology with Dysteria and the analyses from both mtSSU-rDNA and nSSU-rDNA; (3) Brooklynella is confirmed to be an intermediate taxon between Dysteriidae and Hartmannulidae, and may represent a distinct family; (4) Trithigmostoma should remain in Chilodonellidae; (5) the separation of Paraspathidium from Litostomatea is supported and it groups with prostomateans and plagiopyleans. In summary, results from mtSSU-rDNA corroborated those of nSSU-rDNA for highly supported clades, and the mtSSU-rDNA tree with its secondary structure gave topologies that could be explained by the morphology; therefore it can be useful in some cases towards better resolution of robust phylogenies.


Asunto(s)
Cilióforos/clasificación , Cilióforos/genética , ADN Protozoario , ADN Ribosómico/genética , Genoma de Protozoos , Mitocondrias/genética , Filogenia , Subunidades Ribosómicas Pequeñas/genética , Análisis de Secuencia de ADN
13.
Eur J Protistol ; 94: 126088, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38744183

RESUMEN

The morphology and morphogenesis of Lamtostyla paravitiphila nov. spec., a novel soil hypotrichous ciliate collected from eastern China, were investigated based on live observations and protargol-stained specimens. The new species is morphologically characterized as follows: seven to twelve macronuclear nodules, cortical granules absent, 19-26 adoral membranelles, three or four frontoventral cirri, the amphisiellid median cirral row extends to about mid-body and composed of 12-18 cirri, two or three transverse cirri, 27-39 left and 30-41 right marginal cirri, three almost bipolar dorsal kineties. Morphogenetically, it is characterized by the initial formation of six frontal-ventral-transverse cirral anlagen as primary primordia. Notably, the amphisiellid median cirral row and the posterior frontoventral cirrus (or cirri) contribute to the development of the frontal-ventral-transverse cirral anlagen, while the buccal cirrus may not participate in this process. Phylogenetic analyses based on small subunit ribosomal DNA sequence data indicate that the Lamtostyla species with available molecular data do not form a monophyletic group.


Asunto(s)
Hypotrichida , Morfogénesis , Filogenia , Suelo , Especificidad de la Especie , Suelo/parasitología , Hypotrichida/genética , Hypotrichida/clasificación , Hypotrichida/citología , China , ARN Ribosómico 18S/genética , Cilióforos/clasificación , Cilióforos/genética , Cilióforos/citología
14.
Aquat Toxicol ; 268: 106861, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38340542

RESUMEN

Abamectin is a globally used pesticide, which is one of 16-member macrocyclic lactones compound. As an environmental contaminant, pesticide residues pose a great threat to the health and survival of aquatic animals. Procambarus clarkii is one of the most important economic aquatic animals in China. It is necessary to explore the toxic mechanism of abamectin to P. clarkii. In this study, the toxic mechanism of abamectin to P. clarkii was investigated by 0, 3 and 6 µg/L abamectin stress for 28 days. The digestive-, antioxidant- and immune- related enzymes activities, genes expression levels, and histological observations were analytical indicators of growth performance, digestive capacity, and defense systems. The results in this study showed that with abamectin concentration increasing, the growth of P. clarkii was stunted significantly, and the mortality rate increased significantly. With exposure time and abamectin concentration increasing, the expression levels of related genes, the activities of digestive-, antioxidant-, and immune- related enzymes decreased ultimately. Moreover, through histological observation, it was found that with abamectin concentration increasing, the hepatopancreas, muscle, and intestine were damaged. As elucidated by the results, once abamectin exists in the environment for a long time, even low doses will threaten to healthy growth and survival of P. clarkii. This study explored the potential toxicity and the toxic mechanism of abamectin to P. clarkii, and provides a theoretical basis for further study on the toxicity of pesticides to aquatic animals.


Asunto(s)
Ivermectina/análogos & derivados , Plaguicidas , Contaminantes Químicos del Agua , Animales , Antioxidantes/metabolismo , Astacoidea/metabolismo , Contaminantes Químicos del Agua/toxicidad , Ivermectina/toxicidad , Plaguicidas/metabolismo
15.
Adv Mater ; 36(2): e2308706, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37983869

RESUMEN

All-perovskite tandem solar cells offer the potential to surpass the Shockley-Queisser (SQ) limit efficiency of single-junction solar cells while maintaining the advantages of low-cost and high-productivity solution processing. However, scalable solution processing of electron transport layer (ETL) in p-i-n structured perovskite solar subcells remains challenging due to the rough perovskite film surface and energy level mismatch between ETL and perovskites. Here, scalable solution processing of hybrid fullerenes (HF) with blade-coating on both wide-bandgap (≈1.80 eV) and narrow-bandgap (≈1.25 eV) perovskite films in all-perovskite tandem solar modules is developed. The HF, comprising a mixture of fullerene (C60 ), phenyl C61 butyric acid methyl ester, and indene-C60 bisadduct, exhibits improved conductivity, superior energy level alignment with both wide- and narrow-bandgap perovskites, and reduced interfacial nonradiative recombination when compared to the conventional thermal-evaporated C60 . With scalable solution-processed HF as the ETLs, the all-perovskite tandem solar modules achieve a champion power conversion efficiency of 23.3% (aperture area = 20.25 cm2 ). This study paves the way to all-solution processing of low-cost and high-efficiency all-perovskite tandem solar modules in the future.

16.
Nat Commun ; 15(1): 4907, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38851760

RESUMEN

Perovskite/silicon tandem solar cells hold great promise for realizing high power conversion efficiency at low cost. However, achieving scalable fabrication of wide-bandgap perovskite (~1.68 eV) in air, without the protective environment of an inert atmosphere, remains challenging due to moisture-induced degradation of perovskite films. Herein, this study reveals that the extent of moisture interference is significantly influenced by the properties of solvent. We further demonstrate that n-Butanol (nBA), with its low polarity and moderate volatilization rate, not only mitigates the detrimental effects of moisture in air during scalable fabrication but also enhances the uniformity of perovskite films. This approach enables us to achieve an impressive efficiency of 29.4% (certified 28.7%) for double-sided textured perovskite/silicon tandem cells featuring large-size pyramids (2-3 µm) and 26.3% over an aperture area of 16 cm2. This advance provides a route for large-scale production of perovskite/silicon tandem solar cells, marking a significant stride toward their commercial viability.

17.
Eur J Protistol ; 91: 126031, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37925832

RESUMEN

Erniella Foissner, 1987 is a poorly known genus with its available information limited solely to morphological characteristics. In this study, the type species E. filiformis, isolated from highly saline water in China, was investigated for morphology, morphogenesis, and phylogeny based on small subunit ribosomal DNA sequences. The main characteristic events during morphogenesis in Erniella filiformis are as follows: (1) in the proter, only the posterior part of the parental adoral zone is renewed and undulating membranes anlage is formed from the dedifferentiation of the old structure; (2) the oral primordium is formed intrakinetally in the opisthe; (3) frontoventral-transverse cirral anlagen II-IV develop in the primary mode, anlage V develops intrakinetally in the proter; and (4) the right frontoventral row is formed by a single anlage. The phylogenetic analyses indicate that Erniella forms a monophyletic group with Bistichella, Keronopsis, Lamtostyla, Orthoamphisiella, Parabistichella, Paraholosticha, and Uroleptoides.


Asunto(s)
Cilióforos , Hypotrichida , Filogenia , ADN Ribosómico/genética , China , Morfogénesis , Cilióforos/genética , Hypotrichida/genética
18.
Biomater Sci ; 11(8): 2775-2786, 2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-36825578

RESUMEN

Robust and antibacterial dental resins are essential for repairing the shape and function of the teeth. However, an ingenious way to achieve a synergistic enhancement of these two properties is still lacking. In this work, guided by molecular dynamics (MD) calculations, a boron nitride nanosheet (BNN)/titanium dioxide (TiO2) nanocomposite system was synthesized and used to modify the dental flow resin to enhance its mechanical and antimicrobial properties. The mechanical and antimicrobial enhancement mechanisms were further explored. The modified resin demonstrated outstanding performance improvement with 88.23%, 58.47%, 82.01%, and 55.06% improvement in compressive strength (CS), microhardness (MH), flexural strength (FS), and elastic modulus (EM), respectively. Moreover, the modified resin could effectively inhibit the growth of Streptococcus mutans (S. mutans) regardless of aging in water and the inhibition rates were more than 90%. In conclusion, the modified resin is expected to be an ideal restorative material for clinical applications.


Asunto(s)
Antibacterianos , Nanocompuestos , Resinas Sintéticas , Antibacterianos/química , Resinas Sintéticas/química , Fenómenos Mecánicos
19.
Mar Life Sci Technol ; 5(3): 300-315, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37637252

RESUMEN

One of the most diverse clades of ciliated protozoa, the class Spirotrichea, displays a series of unique characters in terms of eukaryotic macronuclear (MAC) genome, including high fragmentation that produces nanochromosomes. However, the genomic diversity and evolution of nanochromosomes and gene families for spirotrich MAC genomes are poorly understood. In this study, we assemble the MAC genome of a representative euplotid (a new model organism in Spirotrichea) species, Euplotes aediculatus. Our results indicate that: (a) the MAC genome includes 35,465 contigs with a total length of 97.3 Mb and a contig N50 of 3.4 kb, and contains 13,145 complete nanochromosomes and 43,194 predicted genes, with the majority of these nanochromosomes containing tiny introns and harboring only one gene; (b) genomic comparisons between E. aediculatus and other reported spirotrichs indicate that average GC content and genome fragmentation levels exhibit interspecific variation, and chromosome breaking sites (CBSs) might be lost during evolution, resulting in the increase of multi-gene nanochromosome; (c) gene families associated with chitin metabolism and FoxO signaling pathway are expanded in E. aediculatus, suggesting their potential roles in environment adaptation and survival strategies of E. aediculatus; and (d) a programmed ribosomal frameshift (PRF) with a conservative motif 5'-AAATAR-3' tends to occur in longer genes with more exons, and PRF genes play an important role in many cellular regulation processes. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-023-00175-0.

20.
Adv Ther (Weinh) ; 6(12): 2300209, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38249990

RESUMEN

The immune system plays a crucial role in recognizing and eliminating pathogenic substances and malignant cells in the body. For cancer treatment, immunotherapy is becoming the standard treatment for many types of cancer and is often combined with chemotherapy. Although chemotherapeutic agents are often reported to have adverse effects, including immunosuppression, they can also play a positive role in immunotherapy by directly stimulating the immune system. This has been demonstrated in preclinical and clinical studies in the past decades. Chemotherapeutics can activate immune cells through different immune receptors and signaling pathways depending on their chemical structure and formulation. In this review, we summarize and discuss the direct immunoactivation effects of chemotherapeutics and possible mechanisms behind these effects. Finally, we prospect chemo-immunotherapeutic combinations for the more effective and safer treatment of cancer.

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