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1.
Cell ; 186(7): 1352-1368.e18, 2023 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-37001500

RESUMEN

Resilience enables mental elasticity in individuals when rebounding from adversity. In this study, we identified a microcircuit and relevant molecular adaptations that play a role in natural resilience. We found that activation of parvalbumin (PV) interneurons in the primary auditory cortex (A1) by thalamic inputs from the ipsilateral medial geniculate body (MG) is essential for resilience in mice exposed to chronic social defeat stress. Early attacks during chronic social defeat stress induced short-term hyperpolarizations of MG neurons projecting to the A1 (MGA1 neurons) in resilient mice. In addition, this temporal neural plasticity of MGA1 neurons initiated synaptogenesis onto thalamic PV neurons via presynaptic BDNF-TrkB signaling in subsequent stress responses. Moreover, optogenetic mimicking of the short-term hyperpolarization of MGA1 neurons, rather than merely activating MGA1 neurons, elicited innate resilience mechanisms in response to stress and achieved sustained antidepressant-like effects in multiple animal models, representing a new strategy for targeted neuromodulation.


Asunto(s)
Corteza Auditiva , Ratones , Animales , Corteza Auditiva/metabolismo , Tálamo/fisiología , Neuronas/metabolismo , Cuerpos Geniculados , Interneuronas/fisiología , Parvalbúminas/metabolismo
2.
Cell ; 183(2): 490-502.e18, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-33002410

RESUMEN

The non-receptor protein tyrosine phosphatase (PTP) SHP2, encoded by PTPN11, plays an essential role in RAS-mitogen-activated protein kinase (MAPK) signaling during normal development. It has been perplexing as to why both enzymatically activating and inactivating mutations in PTPN11 result in human developmental disorders with overlapping clinical manifestations. Here, we uncover a common liquid-liquid phase separation (LLPS) behavior shared by these disease-associated SHP2 mutants. SHP2 LLPS is mediated by the conserved well-folded PTP domain through multivalent electrostatic interactions and regulated by an intrinsic autoinhibitory mechanism through conformational changes. SHP2 allosteric inhibitors can attenuate LLPS of SHP2 mutants, which boosts SHP2 PTP activity. Moreover, disease-associated SHP2 mutants can recruit and activate wild-type (WT) SHP2 in LLPS to promote MAPK activation. These results not only suggest that LLPS serves as a gain-of-function mechanism involved in the pathogenesis of SHP2-associated human diseases but also provide evidence that PTP may be regulated by LLPS that can be therapeutically targeted.


Asunto(s)
Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Células A549 , Animales , Niño , Preescolar , Femenino , Mutación con Ganancia de Función/genética , Células HEK293 , Células Endoteliales de la Vena Umbilical Humana , Humanos , Sistema de Señalización de MAP Quinasas/fisiología , Masculino , Ratones , Células Madre Embrionarias de Ratones , Mutación/genética , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Transducción de Señal , Dominios Homologos src/genética
3.
Genes Dev ; 37(5-6): 204-217, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36921996

RESUMEN

Although it is well established that Huntington's disease (HD) is mainly caused by polyglutamine-expanded mutant huntingtin (mHTT), the molecular mechanism of mHTT-mediated actions is not fully understood. Here, we showed that expression of the N-terminal fragment containing the expanded polyglutamine (HTTQ94) of mHTT is able to promote both the ACSL4-dependent and the ACSL4-independent ferroptosis. Surprisingly, inactivation of the ACSL4-dependent ferroptosis fails to show any effect on the life span of Huntington's disease mice. Moreover, by using RNAi-mediated screening, we identified ALOX5 as a major factor required for the ACSL4-independent ferroptosis induced by HTTQ94. Although ALOX5 is not required for the ferroptotic responses triggered by common ferroptosis inducers such as erastin, loss of ALOX5 expression abolishes HTTQ94-mediated ferroptosis upon reactive oxygen species (ROS)-induced stress. Interestingly, ALOX5 is also required for HTTQ94-mediated ferroptosis in neuronal cells upon high levels of glutamate. Mechanistically, HTTQ94 activates ALOX5-mediated ferroptosis by stabilizing FLAP, an essential cofactor of ALOX5-mediated lipoxygenase activity. Notably, inactivation of the Alox5 gene abrogates the ferroptosis activity in the striatal neurons from the HD mice; more importantly, loss of ALOX5 significantly ameliorates the pathological phenotypes and extends the life spans of these HD mice. Taken together, these results demonstrate that ALOX5 is critical for mHTT-mediated ferroptosis and suggest that ALOX5 is a potential new target for Huntington's disease.


Asunto(s)
Ferroptosis , Enfermedad de Huntington , Animales , Ratones , Modelos Animales de Enfermedad , Ferroptosis/genética , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Enfermedad de Huntington/genética , Enfermedad de Huntington/metabolismo , Enfermedad de Huntington/patología , Neuronas/metabolismo , Estrés Oxidativo/genética , Especies Reactivas de Oxígeno/metabolismo
4.
Nature ; 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38925147

RESUMEN

Perovskite solar cells (PSCs) with an "inverted" architecture are a key pathway for commercializing this emerging photovoltaic technology due to the better power conversion efficiency (PCE) and operational stability as compared to the "normal" device structure. Specifically, PCEs of the inverted PSCs have exceeded 25% owing to the development of improved self-assembled molecules (SAMs)1-5 and passivation strategies6-8. Nevertheless, poor wettability and agglomerations of SAMs9-12 will cause interfacial losses, impeding further improvement in PCE and stability. Herein, we report on molecular hybrid at the buried interface in inverted PSCs by co-assembling a multiple carboxylic acid functionalized aromatic compound of 4,4',4''-nitrilotribenzoicacid (NA) with a popular SAM of [4-(3,6-dime-thyl-9H-carbazol-9-yl)butyl]phosphonic acid (Me-4PACz) to improve the heterojunction interface. The molecular hybrid of Me-4PACz with NA could substantially improve the interfacial characteristics. The resulting inverted PSCs demonstrated a record-certified steady-state efficiency of 26.54%. Crucially, this strategy aligns seamlessly with large-scale manufacturing, achieving the highest certified PCE for inverted mini-modules at 22.74% (aperture area: 11.1 cm2). Our device also maintained 96.1% of its initial PCE after more than 2,400 hours of 1-sun operation in ambient air.

5.
Genes Dev ; 35(1-2): 59-64, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33303641

RESUMEN

Here, we showed that the acetylation-defective p53-4KR mice, lacking the ability of cell cycle arrest, senescence, apoptosis, and ferroptosis, were tumor prone but failed to develop early-onset tumors. By identifying a novel p53 acetylation site at lysine K136, we found that simultaneous mutations at all five acetylation sites (p53-5KR) diminished its remaining tumor suppression function. Moreover, the embryonic lethality caused by the deficiency of mdm2 was fully rescued in the background of p535KR/5KR , but not p534KR/4KR background. p53-4KR retained the ability to suppress mTOR function but this activity was abolished in p53-5KR cells. Notably, the early-onset tumor formation observed in p535KR/5KR and p53-null mice was suppressed upon the treatment of the mTOR inhibitor. These results suggest that p53-mediated mTOR regulation plays an important role in both embryonic development and tumor suppression, independent of cell cycle arrest, senescence, apoptosis, and ferroptosis.


Asunto(s)
Puntos de Control del Ciclo Celular/genética , Neoplasias/genética , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Acetilación , Animales , Carcinogénesis/efectos de los fármacos , Carcinogénesis/genética , Embrión de Mamíferos , Lisina/genética , Lisina/metabolismo , Ratones , Mutación/genética , Neoplasias/fisiopatología , Proteínas Proto-Oncogénicas c-mdm2/deficiencia , Proteínas Proto-Oncogénicas c-mdm2/genética , Sirolimus/farmacología , Análisis de Supervivencia
6.
Proc Natl Acad Sci U S A ; 120(25): e2302779120, 2023 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-37307493

RESUMEN

Supply of Gibbs free energy and precursors are vital for cellular function and cell metabolism have evolved to be tightly regulated to balance their supply and consumption. Precursors and Gibbs free energy are generated in the central carbon metabolism (CCM), and fluxes through these pathways are precisely regulated. However, how fluxes through CCM pathways are affected by posttranslational modification and allosteric regulation remains poorly understood. Here, we integrated multi-omics data collected under nine different chemostat conditions to explore how fluxes in the CCM are regulated in the yeast Saccharomyces cerevisiae. We deduced a pathway- and metabolism-specific CCM flux regulation mechanism using hierarchical analysis combined with mathematical modeling. We found that increased glycolytic flux associated with an increased specific growth rate was accompanied by a decrease in flux regulation by metabolite concentrations, including the concentration of allosteric effectors, and a decrease in the phosphorylation level of glycolytic enzymes.


Asunto(s)
Procesamiento Proteico-Postraduccional , Saccharomyces cerevisiae , Fosforilación , Regulación Alostérica , Carbono
7.
Proc Natl Acad Sci U S A ; 120(42): e2219589120, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37812694

RESUMEN

NTRK (neurotrophic tyrosine receptor kinase) gene fusions that encode chimeric proteins exhibiting constitutive activity of tropomyosin receptor kinases (TRK), are oncogenic drivers in multiple cancer types. However, the underlying mechanisms in oncogenesis that involve various N-terminal fusion partners of NTRK fusions remain elusive. Here, we show that NTRK fusion proteins form liquid-like condensates driven by their N-terminal fusion partners. The kinase reactions are accelerated in these condensates where the complexes for downstream signaling activation are also concentrated. Our work demonstrates that the phase separation driven by NTRK fusions is not only critical for TRK activation, but the condensates formed through phase separation serve as organizational hubs for oncogenic signaling.


Asunto(s)
Neoplasias , Proteínas de Fusión Oncogénica , Humanos , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Transducción de Señal/genética , Neoplasias/genética , Neoplasias/metabolismo , Fusión Génica , Receptor trkA/genética , Receptor trkA/metabolismo , Inhibidores de Proteínas Quinasas
8.
J Neurosci ; 44(7)2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38124211

RESUMEN

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by persistent deficits in social communication and stereotyped behaviors. Although major advances in basic research on autism have been achieved in the past decade, and behavioral interventions can mitigate the difficulties that individuals with autism experience, little is known about the many fundamental issues of the interventions, and no specific medication has demonstrated efficiency for the core symptoms of ASD. Intermittent hypobaric hypoxia (IHH) is characterized by repeated exposure to lowered atmospheric pressure and oxygen levels, which triggers multiple physiological adaptations in the body. Here, using two mouse models of ASD, male Shank3B -/- and Fmr1 -/y mice, we found that IHH training at an altitude of 5,000 m for 4 h per day, for 14 consecutive days, ameliorated autistic-like behaviors. Moreover, IHH training enhanced hypoxia inducible factor (HIF) 1α in the dorsal raphe nucleus (DRN) and activated the DRN serotonergic neurons. Infusion of cobalt chloride into the DRN, to mimic IHH in increasing HIF1α expression or genetically knockdown PHD2 to upregulate HIF1α expression in the DRN serotonergic neurons, alleviated autistic-like behaviors in Shank3B -/- mice. In contrast, downregulation of HIF1α in DRN serotonergic neurons induced compulsive behaviors. Furthermore, upregulating HIF1α in DRN serotonergic neurons increased the firing rates of these neurons, whereas downregulation of HIF1α in DRN serotonergic neurons decreased their firing rates. These findings suggest that IHH activated DRN serotonergic neurons via upregulation of HIF1α, and thus ameliorated autistic-like phenotypes, providing a novel therapeutic option for ASD.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Ratones , Masculino , Animales , Trastorno Autístico/genética , Trastorno Autístico/terapia , Trastorno del Espectro Autista/genética , Trastorno del Espectro Autista/terapia , Núcleo Dorsal del Rafe , Neuronas Serotoninérgicas/fisiología , Hipoxia , Fenotipo , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil
9.
Hepatology ; 79(2): 289-306, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37540187

RESUMEN

BACKGROUND AND AIMS: Molecular classification is a promising tool for prognosis prediction and optimizing precision therapy for HCC. Here, we aimed to develop a molecular classification of HCC based on the fatty acid degradation (FAD) pathway, fully characterize it, and evaluate its ability in guiding personalized therapy. APPROACH AND RESULTS: We performed RNA sequencing (RNA-seq), PCR-array, lipidomics, metabolomics, and proteomics analysis of 41 patients with HCC, in which 17 patients received anti-programmed cell death-1 (PD-1) therapy. Single-cell RNA sequencing (scRNA-seq) was performed to explore the tumor microenvironment. Nearly, 60 publicly available multiomics data sets were analyzed. The associations between FAD subtypes and response to sorafenib, transarterial chemoembolization (TACE), immune checkpoint inhibitor (ICI) were assessed in patient cohorts, patient-derived xenograft (PDX), and spontaneous mouse model ls. A novel molecular classification named F subtype (F1, F2, and F3) was identified based on the FAD pathway, distinguished by clinical, mutational, epigenetic, metabolic, and immunological characteristics. F1 subtypes exhibited high infiltration with immunosuppressive microenvironment. Subtype-specific therapeutic strategies were identified, in which F1 subtypes with the lowest FAD activities represent responders to compounds YM-155 and Alisertib, sorafenib, anti-PD1, anti-PD-L1, and atezolizumab plus bevacizumab (T + A) treatment, while F3 subtypes with the highest FAD activities are responders to TACE. F2 subtypes, the intermediate status between F1 and F3, are potential responders to T + A combinations. We provide preliminary evidence that the FAD subtypes can be diagnosed based on liquid biopsies. CONCLUSIONS: We identified 3 FAD subtypes with unique clinical and biological characteristics, which could optimize individual cancer patient therapy and help clinical decision-making.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Animales , Ratones , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Sorafenib/uso terapéutico , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Multiómica , Medicina de Precisión , Ácidos Grasos , Microambiente Tumoral
10.
Plant Physiol ; 195(2): 970-985, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38478469

RESUMEN

The Xishuangbanna (XIS) cucumber (Cucumis sativus var. xishuangbannanesis) is a semiwild variety that has many distinct agronomic traits. Here, long reads generated by Nanopore sequencing technology helped assembling a high-quality genome (contig N50 = 8.7 Mb) of landrace XIS49. A total of 10,036 structural/sequence variations (SVs) were identified when comparing with Chinese Long (CL), and known SVs controlling spines, tubercles, and carpel number were confirmed in XIS49 genome. Two QTLs of hypocotyl elongation under low light, SH3.1 and SH6.1, were fine-mapped using introgression lines (donor parent, XIS49; recurrent parent, CL). SH3.1 encodes a red-light receptor Phytochrome B (PhyB, CsaV3_3G015190). A ∼4 kb region with large deletion and highly divergent regions (HDRs) were identified in the promoter of the PhyB gene in XIS49. Loss of function of this PhyB caused a super-long hypocotyl phenotype. SH6.1 encodes a CCCH-type zinc finger protein FRIGIDA-ESSENTIAL LIKE (FEL, CsaV3_6G050300). FEL negatively regulated hypocotyl elongation but it was transcriptionally suppressed by long terminal repeats retrotransposon insertion in CL cucumber. Mechanistically, FEL physically binds to the promoter of CONSTITUTIVE PHOTOMORPHOGENIC 1a (COP1a), regulating the expression of COP1a and the downstream hypocotyl elongation. These above results demonstrate the genetic mechanism of cucumber hypocotyl elongation under low light.


Asunto(s)
Cucumis sativus , Genoma de Planta , Hipocótilo , Sitios de Carácter Cuantitativo , Hipocótilo/crecimiento & desarrollo , Hipocótilo/genética , Cucumis sativus/genética , Cucumis sativus/crecimiento & desarrollo , Sitios de Carácter Cuantitativo/genética , Fitocromo B/genética , Fitocromo B/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Luz
11.
J Biol Chem ; 299(8): 104982, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37390992

RESUMEN

Endoplasmic reticulum (ER) stress and unfolded protein response are cells' survival strategies to thwart disruption of proteostasis. Tumor cells are continuously being challenged by ER stress. The prion protein, PrP, normally a glycosylphosphatidylinositol (GPI)-anchored protein exists as a pro-PrP retaining its GPI-peptide signal sequence in human pancreatic ductal cell adenocarcinoma (PDAC). Higher abundance of pro-PrP indicates poorer prognosis in PDAC patients. The reason why PDAC cells express pro-PrP is unknown. Here, we report that persistent ER stress causes conversion of GPI-anchored PrP to pro-PrP via a conserved ATF6-miRNA449c-5p-PIGV axis. Mouse neurons and AsPC-1, a PDAC cell line, express GPI-anchored PrP. However, continuous culture of these cells with the ER stress inducers thapsigargin or brefeldin A results in the conversion of a GPI-anchored PrP to pro-PrP. Such a conversion is reversible; removal of the inducers allows the cells to re-express a GPI-anchored PrP. Mechanistically, persistent ER stress increases the abundance of an active ATF6, which increases the level of miRNA449c-5p (miR449c-5p). By binding the mRNA of PIGV at its 3'-UTRs, miR449c-5p suppresses the level of PIGV, a mannosyltransferase pivotal in the synthesis of the GPI anchor. Reduction of PIGV leads to disruption of the GPI anchor assembly, causing pro-PrP accumulation and enhancing cancer cell migration and invasion. The importance of ATF6-miR449c-5p-PIGV axis is recapitulated in PDAC biopsies as the higher levels of ATF6 and miR449c-5p and lower levels of PIGV are markers of poorer outcome for patients with PDAC. Drugs targeting this axis may prevent PDAC progression.


Asunto(s)
Adenocarcinoma , Carcinoma Ductal Pancreático , Estrés del Retículo Endoplásmico , Glicosilfosfatidilinositoles , Neoplasias Pancreáticas , Proteínas Priónicas , Animales , Humanos , Ratones , Factor de Transcripción Activador 6/genética , Adenocarcinoma/patología , Glicosilfosfatidilinositoles/metabolismo , Neoplasias Pancreáticas/metabolismo , Proteínas Priónicas/genética , Proteínas Priónicas/metabolismo , Neoplasias Pancreáticas
12.
J Am Chem Soc ; 146(20): 13974-13982, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38723620

RESUMEN

It has been reported that it was selective to produce ammonia on metallic cobalt in the electrocatalytic nitric oxide reduction reaction (eNORR), where hexagonal close-packed (hcp) cobalt outperforms face-centered cubic (fcc) cobalt. However, hydroxylamine is more selectively produced on a cobalt single-atom catalyst (Co-SAC). Herein, we uncover the structural sensitivity over hcp-Co, fcc-Co, and Co-SAC in eNORR by employing a recently developed constant potential simulation method and microkinetic modeling. It was found that the superior activity for ammonia production on hcp-Co can be attributed to its facile electron and proton transfer and a stronger lateral suppression effect from NO* over fcc-Co. The exceptional hydroxylamine selectivity on Co-SAC is due to the modified electronic structure, namely, a positively charged active center. It was found that it is more favorable to produce NOH* over hcp-Co and fcc-Co, while HNO* is more preferable on Co-SAC, which are firmly correlated with the vertical and strong NO adsorption on the former and the moderate adsorption on the latter. In other words, a key factor for selectivity control is the first step of NO* protonation. Therefore, the local structure and electronic structure of the catalysts can be critical in regulating the activity and selectivity in eNORR.

13.
J Am Chem Soc ; 146(2): 1619-1626, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38166387

RESUMEN

Operation of rechargeable batteries at ultralow temperature is a significant practical problem because of poor kinetics of the electrode. Here, we report for the first time stabilized multiphase conversions for fast kinetics and long-term durability in ultralow-temperature, organic-sodium batteries. We establish that disodium rhodizonate organic electrode in conjunction with single-layer graphene oxide obviates consumption of organic radical intermediates, and demonstrate as a result that the newly designed organic electrode exhibits excellent electrochemical performance of a highly significant capacity of 130 mAh g-1 at -50 °C. We evidence that the full-cell configuration coupled with Prussian blue analogues exhibits exceptional cycling stability of >7000 cycles at -40 °C while maintaining a discharge capacity of 101 mAh g-1 at a high current density 300 mA g-1. We show this is among the best reported ultralow-temperature performance for nonaqueous batteries, and importantly, the pouch cell exhibits a continuous power supply despite conditions of -50 °C. This work sheds light on the distinct energy storage characteristics of organic electrode and opens up new avenues for the development of reliable and sustainable ultralow-temperature batteries.

14.
Small ; 20(12): e2307960, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37946615

RESUMEN

The quality of two-step processed perovskites is significantly influenced by the distribution of organic amine salts. Especially, modulating the distribution of organic amine salts remains a grand challenge for sequential vapor-deposited perovskites due to the blocking effect of bottom compact PbI2. Herein, an ultrahigh humidity treatment strategy is developed to facilitate the diffusion of formamidinium iodide (FAI) from the top surface to the buried bottom interface on the sequential vapor-deposited bilayer structure. Both experimental and theoretical investigations elucidate the mechanism that moisture helps to i) create FAI diffusion channels by inducing a phase transition from α- to δ-phase in the perovskite, and ii) enhance the diffusivity of FAI by forming hydrogen bonds. This ultrahigh humidity treatment strategy enables the formation of a desired homogeneous and high-quality α-phase after annealing. As a result, a champion efficiency of 22.0% is achieved and 97.5% of its initial performance is maintained after aging for 1050 h under ambient air with a relative humidity of up to 80%. This FAI diffusion strategy provides new insights into the reproducible, scalable, and high-performance sequential vapor-deposited perovskite solar cells.

15.
Small ; : e2404058, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38873880

RESUMEN

Blade-coating stands out as an alternative for fabricating scalable perovskite solar cells. However, it demands special control of the precursor composition regarding nucleation and crystallization and currently exhibits lower performance than the spin-coating process. It is mainly the resulting film morphology and excess lead iodide (PbI2) distribution that influences the optoelectronic properties. Here, the effectiveness of introducing N-Methyl-2-pyrrolidone (NMP) to regulate the structure of the perovskite layer and the redistribution of PbI2 is found. The introduction of NMP leads to the accumulation of excess PbI2, mainly on the top surface, reducing residual PbI2 at the perovskite buried interface. This not only facilitates the passivation of perovskite grain boundaries but also eliminates the potential degradation of the PbI2 triggered by light illumination in the perovskite buried interface. The optimized NMP-modified inverted perovskite solar cell achieves a champion efficiency of 24.5%, among the highest reported blade-coated perovskite solar cells. Furthermore, 13.68 cm2 blading perovskite solar modules are fabricated and demonstrate an efficiency of up to 20.4%. These findings underscore that with proper modulation of precursor composition, blade-coating can be a feasible and superior alternative for manufacturing high-quality perovskite films, paving the way for their large-scale applications in photovoltaic technology.

16.
Mol Ecol ; 33(4): e17241, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38078555

RESUMEN

Across ecology, and particularly within microbial ecology, there is limited understanding how the generation and maintenance of diversity. Although recent work has shown that both local assembly processes and species pools are important in structuring microbial communities, the relative contributions of these mechanisms remain an important question. Moreover, the roles of local assembly processes and species pools are drastically different when explicitly considering the potential for saturation or unsaturation, yet this issue is rarely addressed. Thus, we established a conceptual model that incorporated saturation theory into the microbiological domain to advance the understanding of mechanisms controlling soil bacterial diversity during forest secondary succession. Conceptual model hypotheses were tested by coupling soil bacterial diversity, local assembly processes and species pools using six different forest successional chronosequences distributed across multiple climate zones. Consistent with the unsaturated case proposed in our conceptual framework, we found that species pool consistently affected α-diversity, even while local assembly processes on local richness operate. In contrast, the effects of species pool on ß-diversity disappeared once local assembly processes were taken into account, and changes in environmental conditions during secondary succession led to shifts in ß-diversity through mediation of the strength of heterogeneous selection. Overall, this study represents one of the first to demonstrate that most local bacterial communities might be unsaturated, where the effect of species pool on α-diversity is robust to the consideration of multiple environmental influences, but ß-diversity is constrained by environmental selection.


Asunto(s)
Biodiversidad , Microbiota , Bosques , Ecología , Bacterias/genética , Suelo , Ecosistema
17.
Opt Express ; 32(12): 21663-21670, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38859515

RESUMEN

1.5 µm wavelength high power buried heterojunction (BH) semiconductor lasers having dilute waveguide structure have been fabricated. The optical field is dragged down toward the n side of the device by the dilute waveguide layer, lowering the optical confinement factor of the p doped material and active material, which helps to enlarge the laser output light power. Compared with thick InGaAsP cladding layer, the dilute waveguide material is easy to be grown and has higher thermal conductivity. The slope efficiency of the obtained dilute waveguide BH lasers is notably higher than that of the BH lasers having no dilute waveguide. Our studies show that the dilute waveguide structure is promising for the fabrication of high power BH lasers.

18.
Acta Neuropathol ; 147(1): 65, 2024 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-38557897

RESUMEN

Human microglia are critically involved in Alzheimer's disease (AD) progression, as shown by genetic and molecular studies. However, their role in tau pathology progression in human brain has not been well described. Here, we characterized 32 human donors along progression of AD pathology, both in time-from early to late pathology-and in space-from entorhinal cortex (EC), inferior temporal gyrus (ITG), prefrontal cortex (PFC) to visual cortex (V2 and V1)-with biochemistry, immunohistochemistry, and single nuclei-RNA-sequencing, profiling a total of 337,512 brain myeloid cells, including microglia. While the majority of microglia are similar across brain regions, we identified a specific subset unique to EC which may contribute to the early tau pathology present in this region. We calculated conversion of microglia subtypes to diseased states and compared conversion patterns to those from AD animal models. Targeting genes implicated in this conversion, or their upstream/downstream pathways, could halt gene programs initiated by early tau progression. We used expression patterns of early tau progression to identify genes whose expression is reversed along spreading of spatial tau pathology (EC > ITG > PFC > V2 > V1) and identified their potential involvement in microglia subtype conversion to a diseased state. This study provides a data resource that builds on our knowledge of myeloid cell contribution to AD by defining the heterogeneity of microglia and brain macrophages during both temporal and regional pathology aspects of AD progression at an unprecedented resolution.


Asunto(s)
Enfermedad de Alzheimer , Animales , Humanos , Enfermedad de Alzheimer/patología , Proteínas tau/genética , Proteínas tau/metabolismo , Transcriptoma , Encéfalo/patología , Células Mieloides/patología , Microglía/patología , Péptidos beta-Amiloides/metabolismo
19.
Opt Lett ; 49(2): 286-289, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38194549

RESUMEN

A single-mode InGaAsP/InP buried heterostructure (BH) laser based on high-order slotted surface gratings has been fabricated. The introduction of surface slotted grating can simplify the fabrication process of single-mode BH lasers notably. The laser shows a good single-mode emission performance, with larger than 30 dB side-mode suppression ratio (SMSR) when the current is between 200 and 400 mA. Calculations show that the gain coupling mechanism plays a key role for the slot grating to select the emission wavelength. The linewidth of the laser is measured. The fitted Gaussian and Lorentzian linewidths are 1500 and 550 kHz, respectively.

20.
Opt Lett ; 49(5): 1377-1380, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38427017

RESUMEN

In this paper, we present a novel, to our knowledge, method for the fabrication of slotted surface gratings for buried heterostructure (BH) lasers. In the device fabrication process, SiO2 strips needed for InP current blocking layer growth are reused for the formation of slot grating pattern masks. In the following growth of the p-InP cladding layer, because the slot areas are covered by SiO2, the InP material is grown selectively in only the areas outside the slot areas, forming slots of the surface gratings in the p-InP layer at the same time as the cladding layer growth. Single longitude mode BH lasers having slotted surface gratings have been fabricated successfully, and the spectra show higher than 40 dB side mode suppression ratio (SMSR). The adoption of the method helps to simply the device fabrication and thus lower the device fabrication cost notably.

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