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1.
Plant Cell ; 35(7): 2464-2483, 2023 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-37062961

RESUMEN

Switch defective/sucrose nonfermentable (SWI/SNF) complexes are evolutionarily conserved multisubunit machines that play vital roles in chromatin architecture regulation for modulating gene expression via sliding or ejection of nucleosomes in eukaryotes. In plants, perturbations of SWI/SNF subunits often result in severe developmental disorders. However, the subunit composition, pathways of assembly, and genomic targeting of the plant SWI/SNF complexes are poorly understood. Here, we report the organization, genomic targeting, and assembly of 3 distinct SWI/SNF complexes in Arabidopsis thaliana: BRAHMA-Associated SWI/SNF complexes (BAS), SPLAYED-Associated SWI/SNF complexes (SAS), and MINUSCULE-Associated SWI/SNF complexes (MAS). We show that BAS complexes are equivalent to human ncBAF, whereas SAS and MAS complexes evolve in multiple subunits unique to plants, suggesting plant-specific functional evolution of SWI/SNF complexes. We further show overlapping and specific genomic targeting of the 3 plant SWI/SNF complexes on chromatin and reveal that SAS complexes are necessary for the correct genomic localization of the BAS complexes. Finally, we define the role of the core module subunit in the assembly of plant SWI/SNF complexes and highlight that ATPase module subunit is required for global complex stability and the interaction of core module subunits in Arabidopsis SAS and BAS complexes. Together, our work highlights the divergence of SWI/SNF chromatin remodelers during eukaryote evolution and provides a comprehensive landscape for understanding plant SWI/SNF complex organization, assembly, genomic targeting, and function.


Asunto(s)
Arabidopsis , Humanos , Arabidopsis/genética , Arabidopsis/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Ensamble y Desensamble de Cromatina/genética , Proteínas Cromosómicas no Histona/genética , Proteínas Cromosómicas no Histona/metabolismo , Cromatina/genética , Cromatina/metabolismo , Genómica
2.
J Am Chem Soc ; 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38943576

RESUMEN

Manipulating single electrons at the atomic scale is vital for mastering complex surface processes governed by the transfer of individual electrons. Polarons, composed of electrons stabilized by electron-phonon coupling, offer a pivotal medium for such manipulation. Here, using scanning tunneling microscopy and spectroscopy (STM/STS) and density functional theory (DFT) calculations, we report the identification and manipulation of a new type of polaron, dubbed van der Waals (vdW) polaron, within mono- to trilayer ultrathin films composed of Sb2O3 molecules that are bonded via vdW attractions. The Sb2O3 films were grown on a graphene-covered SiC(0001) substrate via molecular beam epitaxy. Unlike prior molecular polarons, STM imaging observed polarons at the interstitial sites of the molecular film, presenting unique electronic states and localized band bending. DFT calculations revealed the lowest conduction band as an intermolecular bonding state, capable of ensnaring an extra electron through locally diminished intermolecular distances, thereby forming an intermolecular vdW polaron. We also demonstrated the ability to generate, move, and erase such vdW polarons using an STM tip. Our work uncovers a new type of polaron stabilized by coupling with intermolecular vibrations where vdW interactions dominate, paving the way for designing atomic-scale electron transfer processes and enabling precise tailoring of electron-related properties and functionalities.

3.
Environ Microbiol ; 26(1): e16550, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38087431

RESUMEN

Microbial pigments play a significant role in glacier albedo reduction, thereby contributing to accelerated glacier retreat. The Tibetan Plateau has experienced rapid glacier retreat in recent decades due to global warming, yet there is limited understanding of microbial pigment distribution in the region. Here, we investigated the pigment concentration and composition in cryoconite from four glaciers. Our results showed that chlorophylls were the dominant pigments in Palong No. 4 (PL) and Jiemayangzong (JMYZ) glaciers located in the south of the Tibetan Plateau, while carotenoids were dominant in Qiangyong (QY) and Tanggula (TGL) glaciers located in the central region. Additionally, the chlorophyll b to chlorophyll a ratio, which is an indicator of the algae-to-cyanobacteria ratio, was higher in PL and JMYZ compared to QY and TGL. By using Random Forest Regression and Structural Equation Modelling, we determined that the concentrations of chlorophyll a, chlorophyll b, and carotenoids were associated with autotrophic bacteria relative abundance, climatic factors, and a combination of bacterial and climatic factors, respectively. This study is the first to describe the distribution of microbial pigments in cryoconite from Tibetan glaciers, providing additional support on the influence of algal pigment on glacier retreat.


Asunto(s)
Cianobacterias , Cubierta de Hielo , Cubierta de Hielo/microbiología , Tibet , Clorofila A , Carotenoides
4.
Anal Chem ; 96(3): 1195-1204, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38189664

RESUMEN

Combined in situ analysis of oceanic CO2 concentrations and diverse C and O isotope characteristics can offer a unique perspective with multiple isotopic tracing dimensions for identifying marine biogeochemical processes. Applying this strategy in marine environments is urgently required, yet it faces inherent challenges in terms of existing analytical methods and instruments, e.g., a lack of in situ sensors, limited detectable isotope variety, and low-temporal-resolution data. Here, we report an underwater in situ dissolved CO2 isotope sensor based on mid-infrared tunable diode laser absorption spectroscopy (MIR-TDLAS) and membrane extraction technology. Through the proposed targeted strategies, the sensor is capable of providing high-temporal-resolution in situ measurement of all monosubstituted isotopes of dissolved CO2 (16O13C16O, 18O12C16O, and 17O12C16O) at marine background concentrations. The sensor is demonstrated to provide comparable precision to that of isotope ratio mass spectrometry. At 400 ppmv, the precision for R13C, R18O, and R17O could achieve 0.084, 0.042, and 0.013‰, respectively, for a 1 s integration time. By enabling a high-frequency in situ analysis in fixed-point time-series field deployment, a 17O anomaly with strong regularity is observed, which is not obvious in 18O and 13C, and therefore, the superiority of the proposed multidimensional in situ isotope tracing strategy is demonstrated. The developed sensor has great potential to open up new prospects for advancing marine carbon research.

5.
Small ; 20(14): e2304234, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37994291

RESUMEN

The limited ionic conductivity and unstable interface due to poor solid-solid interface pose significant challenges to the stable cycling of solid-state batteries (SSBs). Herein, an interfacial plasticization strategy is proposed by introducing a succinonitrile (SN)-based plastic curing agent into the polyacrylonitrile (PAN)-based composite polymer electrolytes (CPE) interface. The SN at the interface strongly plasticizes the PAN in the CPE, which reduces the crystallinity of the PAN drastically and enables the CPE to obtain a low modulus surface, but it still maintains a high modulus internally. The reduced crystallinity of PAN provides more amorphous regions, which are favorable for Li+ transport. The gradient modulus structure not only ensures intimate interfacial contact but also favors the suppression of Li dendrites growth. Consequently, the interfacial plasticized CPE (SF-CPE) obtains a high ionic conductivity of 4.8 × 10-4 S cm-1 as well as a high Li+ transference number of 0.61. The Li-Li symmetric cell with SF-CPE can cycle for 1000 h at 0.1 mA cm-2, the LiFeO4 (LFP)-Li full-cell demonstrates a high capacity retention of 86.1% after 1000 cycles at 1 C, and the LiCoO2 (LCO)-Li system also exhibits an excellent cycling performance. This work provides a novel strategy for long-life solid-state batteries.

6.
Plant Cell Environ ; 47(6): 2163-2177, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38481060

RESUMEN

Copper (Cu) is an essential micronutrient for all living organisms but is also highly toxic in excess. Cellular homoeostasis of Cu is maintained by various transporters and metallochaperones. Here, we investigated the biological function of OsCOPT7, a member of the copper transporters (COPT) family, in Cu homoeostasis in rice. OsCOPT7 was mainly expressed in the roots and the expression was upregulated by Cu deficiency. OsCOPT7 was localized at the tonoplast and the endoplasmic reticulum. Knockout of OsCOPT7 increased Cu accumulation in the roots but decreased Cu concentrations in the shoots and grain. The knockout mutants contained higher concentrations of Cu in the roots cell sap but markedly lower concentrations of Cu in the xylem sap than wild-type plants. Seed setting and grain yield were reduced significantly in the knockout mutants grown in a low Cu soil. Knockout mutants were more tolerant to Cu toxicity. Yeast two-hybrid and bimolecular fluorescence complementation assays showed that OsCOPT7 interacts physically with the rice Cu chaperone antioxidant protein 1 (OsATX1). Taken together, our results indicate that OsCOPT7 is a specific Cu transporter functioning to export Cu from the vacuoles and the ER and plays an important role in controlling the root-to-shoot Cu translocation in rice.


Asunto(s)
Cobre , Retículo Endoplásmico , Regulación de la Expresión Génica de las Plantas , Oryza , Proteínas de Plantas , Transporte Biológico , Proteínas de Transporte de Catión/metabolismo , Proteínas de Transporte de Catión/genética , Cobre/metabolismo , Grano Comestible/metabolismo , Grano Comestible/genética , Retículo Endoplásmico/metabolismo , Técnicas de Inactivación de Genes , Oryza/metabolismo , Oryza/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Raíces de Plantas/metabolismo , Brotes de la Planta/metabolismo , Semillas/metabolismo , Semillas/genética , Vacuolas/metabolismo
7.
Opt Express ; 32(11): 18916-18930, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38859038

RESUMEN

Ultraviolet micro-LEDs show great potential as a light source for maskless photolithography. However, there are few reports on micro-LED based maskless photolithography systems, and the studies on the effects of system parameters on exposure patterns are still lacking. Hence, we developed a maskless photolithography system that employs micro-LEDs with peak wavelength 375 nm to produce micrometer-sized exposure patterns in photoresists. We also systematically explored the effects of exposure time and current density of micro-LED on static direct writing patterns, as well as the effects of stage velocity and current pulse width on dynamic direct writing patterns. Furthermore, reducing the size of micro-LED pixels enables obtaining high-resolution exposure patterns, but this approach will bring technical challenges and high costs. Therefore, this paper proposes an oblique direct writing method that, instead of reducing the micro-LED pixel size, improves the pattern resolution by changing the tilt angle of the sample. The experimental results show that the linewidths of the exposed lines decreased by 4.0% and 15.2%, respectively, as the sample tilt angle increased from 0° to 15° and 30°, which confirms the feasibility of the proposed method to improve the pattern resolution. This method is also expected to correct the exposure pattern error caused by optical distortion of the lens in the photolithography system. The system and method reported can be applied in various fields such as PCBs, photovoltaics, solar cells, and MEMS.

8.
Eur J Clin Invest ; 54(4): e14137, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38012826

RESUMEN

BACKGROUND: Atrial fibrillation (AF) is the most common arrhythmia and is associated with considerable morbidity and mortality. Ischaemic heart failure (IHF) remains one of the most common causes of AF in clinical practice. However, ischaemia-mediated mechanisms leading to AF are still incompletely understood, and thus, current treatment approaches are limited. To improve our understanding of the pathophysiology, we studied a porcine IHF model. METHODS: In pigs, IHF was induced by balloon occlusion of the left anterior descending artery for 90 min. After 30 days of reperfusion, invasive haemodynamic measurements and electrophysiological studies were performed. Masson trichrome and immunofluorescence staining were conducted to assess interstitial fibrosis and myofibroblast activation in different heart regions. RESULTS: After 30 days of reperfusion, heart failure with significantly reduced ejection fraction (left anterior obique 30°, 34.78 ± 3.29% [IHF] vs. 62.03 ± 2.36% [control], p < .001; anterior-posterior 0°, 29.16 ± 3.61% vs. 59.54 ± 1.09%, p < .01) was observed. These pigs showed a significantly higher susceptibility to AF (33.90% [IHF] vs. 12.98% [control], p < .05). Histological assessment revealed aggravated fibrosis in atrial appendages but not in atrial free walls in IHF pigs (11.13 ± 1.44% vs. 5.99 ± .86%, p < .01 [LAA], 8.28 ± .56% vs. 6.01 ± .35%, p < .01 [RAA]), which was paralleled by enhanced myofibroblast activation (12.09 ± .65% vs. 9.00 ± .94%, p < .05 [LAA], 14.37 ± .60% vs. 10.30 ± 1.41%, p < .05 [RAA]). Correlation analysis indicated that not fibrosis per se but its cross-regional heterogeneous distribution across the left atrium was associated with AF susceptibility (r = .6344, p < .01). CONCLUSION: Our results suggest that left atrial cross-regional fibrosis difference rather than overall fibrosis level is associated with IHF-related AF susceptibility, presumably by establishing local conduction disturbances and heterogeneity.


Asunto(s)
Fibrilación Atrial , Insuficiencia Cardíaca , Porcinos , Animales , Fibrilación Atrial/complicaciones , Atrios Cardíacos/patología , Fibrosis , Isquemia
9.
Artículo en Inglés | MEDLINE | ID: mdl-38771516

RESUMEN

PURPOSE: Accumulating evidence suggests that neurotensin (NTS) and neurotensin receptors (NTSRs) play key roles in lung cancer progression by triggering multiple oncogenic signaling pathways. This study aims to develop Cu-labeled neurotensin receptor 1 (NTSR1)-targeting agents with the potential for both imaging and therapeutic applications. METHOD: A series of neurotensin receptor antagonists (NRAs) with variable propylamine (PA) linker length and different chelators were synthesized, including [64Cu]Cu-CB-TE2A-iPA-NRA ([64Cu]Cu-4a-c, i = 1, 2, 3), [64Cu]Cu-NOTA-2PA-NRA ([64Cu]Cu-4d), [64Cu]Cu-DOTA-2PA-NRA ([64Cu]Cu-4e, also known as [64Cu]Cu-3BP-227), and [64Cu]Cu-DOTA-VS-2PA-NRA ([64Cu]Cu-4f). The series of small animal PET/CT were conducted in H1299 lung cancer model. The expression profile of NTSR1 was also confirmed by IHC using patient tissue samples. RESULTS: For most of the compounds studied, PET/CT showed prominent tumor uptake and high tumor-to-background contrast, but the tumor retention was strongly influenced by the chelators used. For previously reported 4e, [64Cu]Cu-labeled derivative showed initial high tumor uptake accompanied by rapid tumor washout at 24 h. The newly developed [64Cu]Cu-4d and [64Cu]Cu-4f demonstrated good tumor uptake and tumor-to-background contrast at early time points, but were less promising in tumor retention. In contrast, our lead compound [64Cu]Cu-4b demonstrated 9.57 ± 1.35, 9.44 ± 2.38 and 9.72 ± 4.89%ID/g tumor uptake at 4, 24, and 48 h p.i., respectively. Moderate liver uptake (11.97 ± 3.85, 9.80 ± 3.63, and 7.72 ± 4.68%ID/g at 4, 24, and 48 h p.i.) was observed with low uptake in most other organs. The PA linker was found to have a significant effect on drug distribution. Compared to [64Cu]Cu-4b, [64Cu]Cu-4a had a lower background, including a greatly reduced liver uptake, while the tumor uptake was only moderately reduced. Meanwhile, [64Cu]Cu-4c showed increased uptake in both the tumor and the liver. The clinical relevance of NTSR1 was also demonstrated by the elevated tumor expression in patient tissue samples. CONCLUSIONS: Through the side-by-side comparison, [64Cu]Cu-4b was identified as the lead agent for further evaluation based on its high and sustained tumor uptake and moderate liver uptake. It can not only be used to efficiently detect NTSR1 expression in lung cancer (for diagnosis, patient screening, and treatment monitoring), but also has the great potential to treat NTSR-positive lesions once chelating to the beta emitter 67Cu.

10.
Prev Med ; 185: 108021, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38821420

RESUMEN

OBJECTIVE: Lifestyle factors after cancer diagnosis could influence cancer survival. This study aimed to investigate the joint effects of smoking, physical activity, alcohol consumption, diet and sleep duration on all-cause, cancer and non-cancer mortality of cancer survivors in UK biobank. METHODS: The follow-up period concluded in December 2021, with post-diagnostic lifestyle factors assessed at baseline. A lifestyle score ranging from 0 to 5 was assigned based on adherence to the selected lifestyle factors. The study employed Cox regression models for hazard ratios (HRs) and Kaplan-Meier for survival rates, with stratified and sensitivity analyses to assess the robustness of our findings under various assumptions. RESULTS: During a median follow-up of 12.7 years, 5652 deaths were documented from 34,184 cancer survivors. Compared to scoring 0-1, the HRs (95% CIs) for all-cause mortality with lifestyle scores of 2, 3, 4, and 5 were 0.70 (95% CI: 0.64, 0.76), 0.57 (0.52, 0.62), 0.50 (0.45, 0.54) and 0.43 (0.38, 0.48), respectively. Specific cancer types, particularly digestive, breast, female reproductive, non-solid, and skin cancers, showed notable benefits from adherence to healthy lifestyle, with the HRs of 0.55 (0.39, 0.79), 0.54 (0.42, 0.70), 0.32 (0.19, 0.53), 0.58 (0.39, 0.86), and 0.36 (0.28, 0.46) for lifestyle score of 5, respectively. Stratified analyses indicated the association was particularly significant among those with normal/lower BMI and higher Townsend Deprivation Index (Pinteraction = 0.001 and < 0.001, respectively). CONCLUSIONS: Healthier lifestyles were significantly linked with reduced mortality among cancer survivors. These findings highlight the need for adherence to healthy lifestyle habits to improve survival.

11.
Nanotechnology ; 35(13)2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-37802048

RESUMEN

Sliding grating-structured triboelectric nanogenerators (SG-TENGs) can multiply transferred charge, reduce open-circuit voltage, and increase short-circuit current, which have wide application prospects in self-powered systems. However, conventional SG-TENGs have an ultrahigh internal equivalent impedance, which reduces the output voltage and energy under low load resistances (<10 MΩ). The Pulsed SG-TENGs can reduce the equivalent impedance to near zero by introducing a synchronously triggered mechanical switch (STMS), but its limited output time causes the incomplete charge transfer under high load resistances (>1 GΩ). In this paper, a conventional and pulsed hybrid SG-TENG (CPH-SG-TENG) is developed through rational designing STMS with tunable width and output time. The matching relationship among grid electrode width, contactor width of STMS, sliding speed, and load resistance has been studied, which provides a feasible solution for simultaneous realization of high output energy under small load resistances and high output voltage under high load resistances. The impedance matching range is extended from zero to at least 10 GΩ. The output performance of CPH-SG-TENG under low and high load resistances are demonstrated by passive power management circuit and arc discharge, respectively. The general strategy using tunable STMS combines the advantages of conventional and pulsed TENGs, which has broad application prospects in the fields of TENGs and self-powered systems.

12.
Mol Biol Rep ; 51(1): 776, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38904879

RESUMEN

BACKGROUND: Traumatic hemorrhagic shock (THS) is a complex pathophysiological process resulting in multiple organ failure. Intestinal barrier dysfunction is one of the mechanisms implicated in multiple organ failure. The present study aimed to explore the regulatory role of mitogen-activated protein kinase kinase 3 (MKK3) in THS-induced intestinal injury and to elucidate its potential mechanism. METHODS: Rats were subjected to trauma and hemorrhage to establish a THS animal model. MKK3-targeted lentiviral vectors were injected via the tail vein 72 h before modeling. Twelve hours post-modeling, the mean arterial pressure (MAP) and heart rate (HR) were monitored, and histological injury to the intestine was assessed via H&E staining and transmission electron microscopy. Mitochondrial function and mitochondrial reactive oxygen species (ROS) were evaluated. IEC-6 cells were exposed to hypoxia to mimic intestinal injury following THS in vitro. RESULTS: MKK3 deficiency alleviated intestinal injury and restored mitochondrial function in intestinal tissues from THS-induced rats and hypoxia-treated IEC-6 cells. In addition, MKK3 deficiency promoted Sirt1/PGC-1α-mediated mitochondrial biogenesis and restricted Pink1/Parkin-mediated mitophagy in the injured intestine and IEC-6 cells. Furthermore, the protective effect of MKK3 knockdown against hypoxia-induced mitochondrial damage was strengthened upon simultaneous LC3B/Pink1/Parkin knockdown or weakened upon simultaneous Sirt1 knockdown. CONCLUSION: MKK3 deficiency protected against intestinal injury induced by THS by promoting mitochondrial biogenesis and restricting excessive mitophagy.


Asunto(s)
Intestinos , MAP Quinasa Quinasa 3 , Mitocondrias , Especies Reactivas de Oxígeno , Choque Hemorrágico , Animales , Masculino , Ratas , Línea Celular , Modelos Animales de Enfermedad , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Intestinos/patología , MAP Quinasa Quinasa 3/metabolismo , MAP Quinasa Quinasa 3/genética , Mitocondrias/metabolismo , Mitofagia , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Choque Hemorrágico/complicaciones , Choque Hemorrágico/metabolismo , Choque Hemorrágico/genética , Choque Traumático/metabolismo , Choque Traumático/complicaciones , Choque Traumático/genética
13.
Cell Mol Biol (Noisy-le-grand) ; 70(1): 219-225, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38372092

RESUMEN

Inhibiting mesangial cell proliferation is one of the strategies to control the early progression of diabetic nephropathy (DN). GSK3ß is closely related to cell apoptosis as well as the development of DN, but whether it acts on the proliferation of mesangial cells is unclear. This study aimed to elucidate the role and mechanism of GSK3ß-mediated lncRNA in high glucose-induced mesangial cell proliferation. HBZY-1 cells were used to establish the cell model of DN. The automatic cell counter was applied to assess cell proliferation. Flow cytometry was used to detect cell apoptosis and intracellular ROS levels. High-throughput transcriptomics sequencing was performed to detect the different expressions of long noncoding RNAs (lncRNAs) in the cell model of DN after knocking down the expression of GSK3ß by the transfection of siRNA. The expression of RNA was detected by real-time PCR. In the cell model of DN using HBZY-1 cells, cell proliferation was enhanced accompanied by GSK3ß activation and elevated apoptosis rate and reactive oxygen species (ROS) levels. A panel of novel lncRNAs, which were differentially expressed after GSK3ß knockdown in the cell model of DN, were identified by high-throughput transcriptomics sequencing. Among them, the expression of TCONS_00071187 was upregulated under high glucose conditions while the knockdown of the GSK3ß expression led to the downregulation of TCONS_00071187. The knockdown of TCONS_00071187 resulted in reduced mesangial cell proliferation, and decreased apoptosis rates and ROS levels. In conclusion, GSK3ß promoted mesangial cell proliferation by upregulating TCONS_00071187, which led to enhanced ROS production under high glucose conditions in the cell model of DN. This study revealed the role of GSK3ß medicated lncRNAs in the development of DN.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , Glucógeno Sintasa Quinasa 3 beta , ARN Largo no Codificante , Proliferación Celular/genética , Nefropatías Diabéticas/genética , Nefropatías Diabéticas/metabolismo , Glucosa/toxicidad , Glucógeno Sintasa Quinasa 3 beta/genética , Especies Reactivas de Oxígeno , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Animales , Ratas
14.
Proc Natl Acad Sci U S A ; 118(20)2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-33990466

RESUMEN

Real-world decisions are often open ended, with goals, choice options, or evaluation criteria conceived by decision-makers themselves. Critically, the quality of decisions may heavily rely on the generation of options, as failure to generate promising options limits, or even eliminates, the opportunity for choosing them. This core aspect of problem structuring, however, is largely absent from classical models of decision-making, thereby restricting their predictive scope. Here, we take a step toward addressing this issue by developing a neurally inspired cognitive model of a class of ill-structured decisions in which choice options must be self-generated. Specifically, using a model in which semantic memory retrieval is assumed to constrain the set of options available during valuation, we generate highly accurate out-of-sample predictions of choices across multiple categories of goods. Our model significantly and substantially outperforms models that only account for valuation or retrieval in isolation or those that make alternative mechanistic assumptions regarding their interaction. Furthermore, using neuroimaging, we confirm our core assumption regarding the engagement of, and interaction between, semantic memory retrieval and valuation processes. Together, these results provide a neurally grounded and mechanistic account of decisions with self-generated options, representing a step toward unraveling cognitive mechanisms underlying adaptive decision-making in the real world.


Asunto(s)
Encéfalo/fisiología , Conducta de Elección/fisiología , Cognición/fisiología , Toma de Decisiones/fisiología , Modelos Neurológicos , Adulto , Encéfalo/anatomía & histología , Mapeo Encefálico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Neuroimagen , Web Semántica
15.
Chem Soc Rev ; 52(1): 163-195, 2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36454225

RESUMEN

Lead halide perovskite solar cells (PSCs) have shown unprecedented development in efficiency and progressed relentlessly in improving stability. All the achievements have been accompanied by diverse passivation strategies to circumvent the pervasive defects in perovskite materials, which play crucial roles in the process of charge recombination, ion migration, and component degradation. Among the tremendous efforts made to solve these issues and achieve high-performance PSCs, we classify and review both well-established and burgeoning passivation strategies to provide further guidance for the passivation protocols in PSCs, including chemical passivation to eliminate defects by the formation of chemical bonds, physical passivation to eliminate defects by strain relaxation or physical treatments, energetic passivation to improve the stability toward light and oxygen, and field-effect passivation to regulate the interfacial carrier behavior. The subtle but non-trivial consequences from various passivation strategies need advanced characterization techniques combining synchrotron-based X-ray analysis, capacitance-based measurements, spatially resolved imaging, fluorescent molecular probe, Kelvin probe force microscope, etc., to scrutinize the mechanisms. In the end, challenges and prospective research directions on advancing these passivation strategies are proposed. Judicious combinations among chemical, physical, energetic, and field-effect passivation deserve more attention for future high-efficiency and stable perovskite photovoltaics.

16.
J Environ Manage ; 357: 120807, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38569266

RESUMEN

Vegetation restoration in deserts is challenging due to these ecosystems' inherent fragility and harsh environmental conditions. One approach for active restoration involves planting native species, which can accelerate the recovery of ecosystem functions. To ensure the effectiveness of this process, carefully selecting species for planting is crucial. Generally, it is expected that a more diverse mix of species in the plantation will lead to the recovery of a greater number of ecosystem functions, especially when the selected species have complementary niche traits that facilitate maximum cooperation and minimize competition among them. In this study, we evaluated the planting of two native species from the hyper-desert of Taklamakan, China, which exhibit marked morpho-physiological differences: a phreatophytic legume (Alhagi sparsifolia) and a halophytic non-legume (Karelinia caspia). These species were grown in both monoculture and intercrop communities. Monoculture of the legume resulted in the highest biomass accumulation. Intercropping improved several ecosystem functions in the 50 cm-upper soil, particularly those related to phosphorus (P), carbon (C), and sulfur (S) concentrations, as well as soil enzyme activities. However, it also increased soil sodium (Na+) concentration and pH. Halophyte monocultures enhanced ecological functions associated with nitrogen concentrations in the upper soil and with P, S, C, and cation concentrations (K+, Ca2+, Mg2+, Cu2+, Fe2+, Zn2+, Co2+, Ni2+), along with enzyme activities in the deep soil. It also maximized Na+ accumulation in plant biomass. In summary, we recommend legume monoculture when the primary goal is to optimize biomass accumulation. Conversely, halophyte monoculture is advisable when the objective is to extract sodium from the soil or enhance ecosystem functions in the deep soil. Intercropping the two species is recommended to maximize the ecosystem functions of the upper soil, provided there is no salinization risk. When planning restoration efforts in desert regions, it is essential to understand the impact of each species on ecosystem function and how complementary species behave when intercropped. However, these interactions are likely species- and system-specific, highlighting the need for more work to optimize solutions for different arid ecosystems.


Asunto(s)
Ecosistema , Fabaceae , Biomasa , Suelo , Verduras , Plantas Tolerantes a la Sal , Sodio , China
17.
Water Sci Technol ; 89(7): 1757-1770, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38619901

RESUMEN

The water reuse facilities of industrial parks face the challenge of managing a growing variety of wastewater sources as their inlet water. Typically, this clustering outcome is designed by engineers with extensive expertise. This paper presents an innovative application of unsupervised learning methods to classify inlet water in Chinese water reuse stations, aiming to reduce reliance on engineer experience. The concept of 'water quality distance' was incorporated into three unsupervised learning clustering algorithms (K-means, DBSCAN, and AGNES), which were validated through six case studies. Of the six cases, three were employed to illustrate the feasibility of the unsupervised learning clustering algorithm. The results indicated that the clustering algorithm exhibited greater stability and excellence compared to both artificial clustering and ChatGPT-based clustering. The remaining three cases were utilized to showcase the reliability of the three clustering algorithms. The findings revealed that the AGNES algorithm demonstrated superior potential application ability. The average purity in six cases of K-means, DBSCAN, and AGNES were 0.947, 0.852, and 0.955, respectively.


Asunto(s)
Bahías , Aprendizaje Automático no Supervisado , Reproducibilidad de los Resultados , Algoritmos , Análisis por Conglomerados
18.
Angew Chem Int Ed Engl ; : e202406441, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38742483

RESUMEN

Transition-metal carbides with metallic properties have been extensively used as electrocatalysts due to their excellent conductivity and unique electronic structures. Herein, NbC nanoparticles decorated carbon nanofibers (NbC@CNFs) are proposed as an efficient and robust catalyst for electrochemical synthesis of ammonia from nitrate/nitrite reduction, which achieves a high Faradaic efficiency (FE) of 94.4 % and a large ammonia yield of 30.9 mg h-1 mg-1 cat.. In situ electrochemical tests reveal the nitrite reduction at the catalyst surface follows the *NO pathway and theoretical calculations reveal the formation of NbC@CNFs heterostructure significantly broadens density of states nearby the Fermi energy. Finite element simulations unveil that the current and electric field converge on the NbC nanoparticles along the fiber, suggesting the dispersed carbides are highly active for nitrite reduction.

19.
Neuroimage ; 283: 120442, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37926217

RESUMEN

The ability of humans to discern facial expressions in a timely manner typically relies on distributed face-selective regions for rapid neural computations. To study the time course in regions of interest for this process, we used magnetoencephalography (MEG) to measure neural responses participants viewed facial expressions depicting seven types of emotions (happiness, sadness, anger, disgust, fear, surprise, and neutral). Analysis of the time-resolved decoding of neural responses in face-selective sources within the inferior parietal cortex (IP-faces), lateral occipital cortex (LO-faces), fusiform gyrus (FG-faces), and posterior superior temporal sulcus (pSTS-faces) revealed that facial expressions were successfully classified starting from ∼100 to 150 ms after stimulus onset. Interestingly, the LO-faces and IP-faces showed greater accuracy than FG-faces and pSTS-faces. To examine the nature of the information processed in these face-selective regions, we entered with facial expression stimuli into a convolutional neural network (CNN) to perform similarity analyses against human neural responses. The results showed that neural responses in the LO-faces and IP-faces, starting ∼100 ms after the stimuli, were more strongly correlated with deep representations of emotional categories than with image level information from the input images. Additionally, we observed a relationship between the behavioral performance and the neural responses in the LO-faces and IP-faces, but not in the FG-faces and lpSTS-faces. Together, these results provided a comprehensive picture of the time course and nature of information involved in facial expression discrimination across multiple face-selective regions, which advances our understanding of how the human brain processes facial expressions.


Asunto(s)
Mapeo Encefálico , Expresión Facial , Humanos , Imagen por Resonancia Magnética/métodos , Encéfalo/fisiología , Emociones/fisiología
20.
J Am Chem Soc ; 145(42): 23048-23056, 2023 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-37735109

RESUMEN

Although mRNA delivery technology is very promising, problems in safety and transport arise due to the intrinsically low thermodynamic stability of the current mRNA carriers. Considering that mRNAs are filamentous and a nanotube is one of the most thermodynamically stable shapes among nanoassemblies, a nanotube is one of the most stable supramolecular structures that can be assembled with mRNA. Here, we develop a nanotube-shaped filamentous mRNA delivery platform that shows exceptionally high thermodynamic stability. The key to the development of the mRNA nanotube is the design of self-adjusting supramolecular building blocks (SABs) that have two disparate properties, i.e., dynamic property and stiffness, in a single molecule. The counterbalance of the dynamic property and stiffness in SABs enables the coating of mRNA by winding its way through the flexible and irregular mRNA chain via cooperative interactions. SAB nanotubes with targeting ligands installed show a high uptake efficiency in mammalian cells and controllable gene expression behavior. Thus, the mRNA nanotube provides an enabling technology toward the development of safe and stable mRNA vaccines and therapeutics.


Asunto(s)
Nanotubos , Nanotubos/química , Nanotecnología , Conformación Proteica en Hélice alfa , Termodinámica
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