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1.
J Phys Chem Lett ; 15(23): 6108-6114, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38829304

RESUMO

Two-dimensional metal-organic networks (2D MONs) having heterogeneous coordination nodes (HCNs) could exhibit excellent performance in catalysis and optoelectronics because of the unbalanced electron distribution of the coordinating metals. Therefore, the design and construction of 2D MONs with HCNs are highly desirable but remain challenging. Here, we report the construction of 2D organometallic coordination networks with an organic Kagome lattice and a semiregular metal lattice on Au(111) via the in situ formation of HCNs. Using a bifunctional precursor 1,4-dibromo-2,5-diisocyanobenzene, the coordination of isocyano with Au adatom on a room-temperature Au(111) yielded metal-organic coordination chains with isocyano-Au-isocyano nodes. In contrast, on a high-temperature Au(111), a selective debromination/coordination cascade reaction occurred, affording 2D organometallic coordination networks with phenyl-Au-isocyano nodes. By combining scanning tunneling microscopy and density functional theory calculations, we determined the structures of coordination products and the nature of coordination nodes, demonstrating a thermodynamically favorable pathway for forming the phenyl-Au-isocyano nodes.

2.
Ren Fail ; 46(2): 2359033, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38836372

RESUMO

OBJECTIVE: To determine the efficacy and safety of Astragalus combined with renin-angiotensin-aldosterone system (RAAS) blockers in treating stage III diabetic nephropathy (DN) by meta-analysis. METHODS: PubMed, Embase, Cochrane Library, Wiley, and Web of Science databases were searched for articles published between August 2007 and August 2022. Clinical studies on Astragalus combined with RAAS blockers for the treatment of stage III DN were included. Meta-analysis was performed by RevMan 5.1 and Stata 14.3 software. RESULTS: A total of 32 papers were included in this meta-analysis, containing 2462 patients from randomized controlled trials, with 1244 receiving the combination treatment and 1218 solely receiving RAAS blockers. Astragalus combined with RAAS blockers yielded a significantly higher total effective rate (TER) (mean difference [MD] 3.63, 95% confidence interval [CI] 2.59-5.09) and significantly reduced urinary protein excretion rate (UPER), serum creatinine (Scr), blood urine nitrogen (BUN) and glycosylated hemoglobin (HbAlc) levels. In subgroup analysis, combining astragalus and angiotensin receptor blocker significantly lowered fasting plasma glucose (FPG) and 24 h urinary protein (24hUTP) levels, compared with the combined astragalus and angiotensin-converting enzyme inhibitor treatment. Meanwhile, the latter significantly decreased the urinary microprotein (ß2-MG). Importantly, the sensitivity analysis confirmed the study's stability, and publication bias was not detected for UPER, BUN, HbAlc, FPG, or ß2-MG. However, the TER, SCr, and 24hUTP results suggested possible publication bias. CONCLUSIONS: The astragalus-RAAS blocker combination treatment is safe and improves outcomes; however, rigorous randomized, large-scale, multi-center, double-blind trials are needed to evaluate its efficacy and safety in stage III DN.


Renin-angiotensin-aldosterone system (RAAS) inhibitors are commonly used to treat diabetic neuropathy (DN) and Astragalus membranaceus components are known to improve DN symptoms.We aimed to establish the efficacy and safety of using Astragalus combined with RAAS inhibitors.Astragalus combined with RAAS inhibitors enhances the total effective rate of diabetic neuropathy response to treatment and reduces urinary protein excretion rate, serum creatinine, blood urea nitrogen and HbAlc.Sensitivity analysis affirms study stability, while publication bias was detected for total effective rate, serum creatinine, and 24 h urinary protein levels.


Assuntos
Antagonistas de Receptores de Angiotensina , Inibidores da Enzima Conversora de Angiotensina , Nefropatias Diabéticas , Quimioterapia Combinada , Sistema Renina-Angiotensina , Humanos , Nefropatias Diabéticas/tratamento farmacológico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Sistema Renina-Angiotensina/efeitos dos fármacos , Antagonistas de Receptores de Angiotensina/uso terapêutico , Astrágalo , Ensaios Clínicos Controlados Aleatórios como Assunto , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/administração & dosagem , Resultado do Tratamento , Creatinina/sangue , Hemoglobinas Glicadas , Proteinúria/tratamento farmacológico
3.
Front Microbiol ; 15: 1395583, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38746754

RESUMO

Thermal pollution from the cooling system of the nuclear power plants greatly changes the environmental and the ecological conditions of the receiving marine water body, but we know little about their impact on the steady-state transition of marine bacterioplankton communities. In this study, we used high-throughput sequencing based on the 16S rRNA gene to investigate the impact of the thermal pollution on the bacterioplankton communities in a subtropical bay (the Daya Bay). We observed that thermal pollution from the cooling system of the nuclear power plant caused a pronounced thermal gradient ranging from 19.6°C to 24.12°C over the whole Daya Bay. A temperature difference of 4.5°C between the northern and southern parts of the bay led to a regime shift in the bacterioplankton community structure. In the three typical scenarios of regime shifts, the steady-state transition of bacterioplankton community structure in response to temperature increasing was more likely consistent with an abrupt regime shift rather than a smooth regime or a discontinuous regime model. Water temperature was a decisive factor on the regime shift of bacterioplankton community structure. High temperature significantly decreased bacterioplankton diversity and shifted its community compositions. Cyanobium and Synechococcus of Cyanobacteria, NS5 marine group of Bacteroidota, and Vibrio of Gammaproteobacteria were found that favored high temperature environments. Furthermore, the increased water temperature significantly altered the community assembly of bacterioplankton in Daya Bay, with a substantial decrease in the proportion of drift and others, and a marked increase in the proportion of homogeneous selection. In summary, we proposed that seawater temperature increasing induced by the thermal pollution resulted in an abrupt regime shift of bacterioplankton community in winter subtropical bay. Our research might broad our understanding of marine microbial ecology under future conditions of global warming.

4.
Microsyst Nanoeng ; 10: 70, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38803351

RESUMO

The demand for optically transparent temperature sensors in intelligent devices is increasing. However, the performance of these sensors, particularly in terms of their sensitivity and resolution, must be further enhanced. This study introduces a novel transparent and highly sensitive temperature sensor characterized by its ultrathin, freestanding design based on a Mn-Co-Ni-O nanofilm. The Mn-Co-Ni-O-based sensor exhibits remarkable sensitivity, with a temperature coefficient of resistance of -4% °C-1, and can detect minuscule temperature fluctuations as small as 0.03 °C. Additionally, the freestanding sensor can be transferred onto any substrate for versatile application while maintaining robust structural stability and excellent resistance to interference, indicating its suitability for operation in challenging environments. Its practical utility in monitoring the surface temperature of optical devices is demonstrated through vertical integration of the sensor and a micro light-emitting diode on a polyimide substrate. Moreover, an experiment in which the sensor is implanted in rats confirms its favorable biocompatibility, highlighting the promising applications of the sensor in the biomedical domain.

6.
J Agric Food Chem ; 72(22): 12582-12595, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38788215

RESUMO

Renal tubular ectopic lipid deposition (ELD) plays a significant role in the development of chronic kidney disease, posing a great threat to human health. The present work aimed to explore the intervention effect and potential molecular mechanism of a purified tea polysaccharide (TPS3A) on renal tubular ELD. The results demonstrated that TPS3A effectively improved kidney function and slowed the progression of tubulointerstitial fibrosis in high-fat-diet (HFD)-exposed ApoE-/- mice. Additionally, TPS3A notably suppressed lipogenesis and enhanced lipolysis, as shown by the downregulation of lipogenesis markers (SREBP-1 and FAS) and the upregulation of lipolysis markers (HSL and ATGL), thereby reducing renal tubular ELD in HFD-fed ApoE-/- mice and palmitic-acid-stimulated HK-2 cells. The AMPK-SIRT1-FoxO1 axis is a core signal pathway in regulating lipid deposition. Consistently, TPS3A significantly increased the levels of phosphorylated-AMPK, SIRT1, and deacetylation of Ac-FoxO1. However, these effects of TPS3A on lipogenesis and lipolysis were abolished by AMPK siRNA, SIRT1 siRNA, and FoxO1 inhibitor, resulting in exacerbated lipid deposition. Taken together, TPS3A shows promise in ameliorating renal tubular ELD by inhibiting lipogenesis and promoting lipolysis through the AMPK-SIRT1-FoxO1 signaling pathway.


Assuntos
Dieta Hiperlipídica , Lipogênese , Lipólise , Camundongos Endogâmicos C57BL , Polissacarídeos , Animais , Lipogênese/efeitos dos fármacos , Camundongos , Lipólise/efeitos dos fármacos , Masculino , Dieta Hiperlipídica/efeitos adversos , Humanos , Polissacarídeos/farmacologia , Polissacarídeos/administração & dosagem , Sirtuína 1/metabolismo , Sirtuína 1/genética , Proteína Forkhead Box O1/metabolismo , Proteína Forkhead Box O1/genética , Túbulos Renais/metabolismo , Túbulos Renais/efeitos dos fármacos , Camellia sinensis/química , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Extratos Vegetais/farmacologia , Extratos Vegetais/administração & dosagem , Chá/química , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/genética
7.
Nat Commun ; 15(1): 3870, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719875

RESUMO

Micro-thermoelectric coolers are emerging as a promising solution for high-density cooling applications in confined spaces. Unlike thin-film micro-thermoelectric coolers with high cooling flux at the expense of cooling temperature difference due to very short thermoelectric legs, thick-film micro-thermoelectric coolers can achieve better comprehensive cooling performance. However, they still face significant challenges in both material preparation and device integration. Herein, we propose a design strategy which combines Bi2Te3-based thick film prepared by powder direct molding with micro-thermoelectric cooler integrated via phase-change batch transfer. Accurate thickness control and relatively high thermoelectric performance can be achieved for the thick film, and the high-density-integrated thick-film micro-thermoelectric cooler exhibits excellent performance with maximum cooling temperature difference of 40.6 K and maximum cooling flux of 56.5 W·cm-2 at room temperature. The micro-thermoelectric cooler also shows high temperature control accuracy (0.01 K) and reliability (over 30000 cooling cycles). Moreover, the device demonstrates remarkable capacity in power generation with normalized power density up to 214.0 µW · cm-2 · K-2. This study provides a general and scalable route for developing high-performance thick-film micro-thermoelectric cooler, benefiting widespread applications in thermal management of microsystems.

8.
J Multidiscip Healthc ; 17: 2371-2387, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38770171

RESUMO

Among cardiovascular diseases, hypertension is the most important risk factor for morbidity and mortality worldwide, and its pathogenesis is complex, involving genetic, dietary and environmental factors. The characteristics of the gut microbiota can vary in response to increased blood pressure (BP) and influence the development and progression of hypertension. This paper describes five aspects of the relationship between hypertension and the gut microbiota, namely, the different types of gut microbiota, metabolites of the gut microbiota, sympathetic activation, gut-brain interactions, the effects of exercise and dietary patterns and the treatment of the gut microbiota through probiotics, faecal microbiota transplantation (FMT) and herbal remedies, providing new clues for the future prevention of hypertension. Diet, exercise and traditional Chinese medicine may contribute to long-term improvements in hypertension, although the effects of probiotics and FMT still need to be validated in large populations.

9.
ACS Appl Mater Interfaces ; 16(20): 26643-26652, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38716902

RESUMO

A scene that contains both old and instant events with a clear motion trail is visually intriguing and dynamic, which can convey a sense of change, transition, or evolution. Developing an eco-friendly delay display system offers a powerful tool for fusing old and instant events, which can be used for visualizing motion trails. Herein, we brighten triplet excitons of carbon nanodots (CNDs) and increase their emission yield by a multidimensional confinement strategy, and the CND-based delay display array is demonstrated. The intense confinement effects via multidimensional confinement strategy suppress nonradiative transitions, and 240% enhancement in the phosphorescence efficiency and 260% enhancement in the lifetime of the CNDs are thus realized. Considering their distinctive phosphorescence performances, a delay display array containing a 4 × 4 CND-based delay lighting device is demonstrated, which can provide ultralong phosphorescence over 7 s, and the motion that occurred in different timelines is recorded clearly. This finding will motivate the investigation of phosphorescent CNDs in motion trail recognition.

10.
Nat Commun ; 15(1): 3943, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38729965

RESUMO

Ferroelectric materials have important applications in transduction, data storage, and nonlinear optics. Inorganic ferroelectrics such as lead zirconate titanate possess large polarization, though they are rigid and brittle. Ferroelectric polymers are light weight and flexible, yet their polarization is low, bottlenecked at 10 µC cm-2. Here we show poly(vinylidene fluoride) nanocomposite with only 0.94% of self-nucleated CH3NH3PbBr3 nanocrystals exhibits anomalously large polarization (~19.6 µC cm-2) while retaining superior stretchability and photoluminance, resulting in unprecedented electromechanical figures of merit among ferroelectrics. Comprehensive analysis suggests the enhancement is accomplished via delicate defect engineering, with field-induced Frenkel pairs in halide perovskite stabilized by the poled ferroelectric polymer through interfacial coupling. The strategy is general, working in poly(vinylidene fluoride-co-hexafluoropropylene) as well, and the nanocomposite is stable. The study thus presents a solution for overcoming the electromechanical dilemma of ferroelectrics while enabling additional optic-activity, ideal for multifunctional flexible electronics applications.

11.
J Phys Chem Lett ; 15(14): 3785-3795, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38557057

RESUMO

The development of cost-effective and anti-coking catalysts for propane dehydrogenation (PDH) is crucial. Here, non-noble metal-incorporated Ni-based catalysts (Ni3M, M = Sc, Ti, V, Mn, Fe, Co, Cu, Zn, Ga, Zr, Nb, Mo, In, Sn) were employed in the PDH process. The introduction of V, Nb, and Mo, with their strong carbon binding ability, created unique Ni-M cooperative sites, enhancing the catalytic performance. Other non-noble metals influenced the electronic structure of Ni, affecting the overall catalytic behavior. V and Nb exhibited a balanced combination of activity, selectivity, and stability, making them potential catalyst candidates. Microkinetic simulations revealed that Ni3V and Ni3Nb displayed high selectivity toward olefins with low apparent activation energies. This study emphasizes the significance of bimetallic synergy in enhancing PDH performance and provides new directions for the development of efficient alkane dehydrogenation catalyst development.

12.
New Phytol ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622812

RESUMO

Boron (B) is crucial for plant growth and development. B deficiency can impair numerous physiological and metabolic processes, particularly in root development and pollen germination, seriously impeding crop growth and yield. However, the molecular mechanism underlying boron signal perception and signal transduction is rather limited. In this study, we discovered that CPK10, a calcium-dependent protein kinase in the CPK family, has the strongest interaction with the boron transporter BOR1. Mutations in CPK10 led to growth and root development defects under B-deficiency conditions, while constitutively active CPK10 enhanced plant tolerance to B deficiency. Furthermore, we found that CPK10 interacted with and phosphorylated BOR1 at the Ser689 residue. Through various biochemical analyses and complementation of B transport in yeast and plants, we revealed that Ser689 of BOR1 is important for its transport activity. In summary, these findings highlight the significance of the CPK10-BOR1 signaling pathway in maintaining B homeostasis in plants and provide targets for the genetic improvement of crop tolerance to B-deficiency stress.

13.
Adv Sci (Weinh) ; : e2304908, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600652

RESUMO

Single-atom alloys (SAAs) have gained increasing prominence in the field of selective hydrogenation reactions due to their uniform distribution of active sites and the unique host-guest metal interactions. Herein, 15 SAAs are constructed to comprehensively elucidate the relationship between host-guest metal interaction and catalytic performance in the selective hydrogenation of 4-nitrostyrene (4-NS) by density functional theory (DFT) calculations. The results demonstrate that the SAAs with strong host-guest metal interactions exhibit a preference for N─O bond cleavage, and the reaction energy barrier of the hydrogenation process is primarily influenced by the host metal. Among them, Ir1Ni SAA stands out as the prime catalyst candidate, showcasing exceptional activity and selectivity. Furthermore, the Ir1Ni SAA is subsequently prepared through precise synthesis techniques and evaluated in the selective hydrogenation of 4-NS to 4-aminostyrene (4-AS). As anticipated, the Ir1Ni SAA demonstrates extraordinary catalytic performance (yield > 96%). In situ FT-IR experiments and DFT calculations further confirmed that the unique host-guest metal interaction at the Ir-Ni interface site of Ir1Ni SAA endows it with excellent 4-NS selective hydrogenation ability. This work provides valuable insights into enhancing the performance of SAAs catalysts in selective hydrogenation reactions by modulating the host-guest metal interactions.

14.
JMIR Med Inform ; 12: e48862, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557661

RESUMO

BACKGROUND: Triage is the process of accurately assessing patients' symptoms and providing them with proper clinical treatment in the emergency department (ED). While many countries have developed their triage process to stratify patients' clinical severity and thus distribute medical resources, there are still some limitations of the current triage process. Since the triage level is mainly identified by experienced nurses based on a mix of subjective and objective criteria, mis-triage often occurs in the ED. It can not only cause adverse effects on patients, but also impose an undue burden on the health care delivery system. OBJECTIVE: Our study aimed to design a prediction system based on triage information, including demographics, vital signs, and chief complaints. The proposed system can not only handle heterogeneous data, including tabular data and free-text data, but also provide interpretability for better acceptance by the ED staff in the hospital. METHODS: In this study, we proposed a system comprising 3 subsystems, with each of them handling a single task, including triage level prediction, hospitalization prediction, and length of stay prediction. We used a large amount of retrospective data to pretrain the model, and then, we fine-tuned the model on a prospective data set with a golden label. The proposed deep learning framework was built with TabNet and MacBERT (Chinese version of bidirectional encoder representations from transformers [BERT]). RESULTS: The performance of our proposed model was evaluated on data collected from the National Taiwan University Hospital (901 patients were included). The model achieved promising results on the collected data set, with accuracy values of 63%, 82%, and 71% for triage level prediction, hospitalization prediction, and length of stay prediction, respectively. CONCLUSIONS: Our system improved the prediction of 3 different medical outcomes when compared with other machine learning methods. With the pretrained vital sign encoder and repretrained mask language modeling MacBERT encoder, our multimodality model can provide a deeper insight into the characteristics of electronic health records. Additionally, by providing interpretability, we believe that the proposed system can assist nursing staff and physicians in taking appropriate medical decisions.

15.
Life Sci Alliance ; 7(6)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38570190

RESUMO

Cardiovascular system develops from the lateral plate mesoderm. Its three primary cell lineages (hematopoietic, endothelial, and muscular) are specified by the sequential actions of conserved transcriptional factors. ETV2, a master regulator of mammalian hemangioblast development, however, is absent in the chicken genome and acts downstream of NPAS4L in zebrafish. Here, we investigated the epistatic relationship between NPAS4L and ETV2 in avian hemangioblast development. We showed that ETV2 is deleted in all 363 avian genomes analyzed. Mouse ETV2 induced LMO2, but not NPAS4L or SCL, expression in chicken mesoderm. Squamate (lizards, geckos, and snakes) genomes contain both NPAS4L and ETV2 In Madagascar ground gecko, both genes were expressed in developing hemangioblasts. Gecko ETV2 induced only LMO2 in chicken mesoderm. We propose that both NPAS4L and ETV2 were present in ancestral amniote, with ETV2 acting downstream of NPAS4L in endothelial lineage specification. ETV2 may have acted as a pioneer factor by promoting chromatin accessibility of endothelial-specific genes and, in parallel with NPAS4L loss in ancestral mammals, has gained similar function in regulating blood-specific genes.


Assuntos
Células-Tronco Hematopoéticas , Peixe-Zebra , Animais , Camundongos , Diferenciação Celular/genética , Células-Tronco Hematopoéticas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Aves , Mamíferos/metabolismo
16.
Kaohsiung J Med Sci ; 40(6): 561-574, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38634140

RESUMO

Slow transit constipation (STC) is one of the most common gastrointestinal disorders in children and adults worldwide. Paeoniflorin (PF), a monoterpene glycoside compound extracted from the dried root of Paeonia lactiflora, has been found to alleviate STC, but the mechanisms of its effect remain unclear. The present study aimed to investigate the effects and mechanisms of PF on intestinal fluid metabolism and visceral sensitization in rats with compound diphenoxylate-induced STC. Based on the evaluation of the laxative effect, the abdominal withdrawal reflex test, enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, western blot, and immunohistochemistry were used to detect the visceral sensitivity, fluid metabolism-related proteins, and acid-sensitive ion channel 3/extracellular signal-regulated kinase (ASIC3/ERK) pathway-related molecules. PF treatment not only attenuated compound diphenoxylate-induced constipation symptoms and colonic pathological damage in rats but also ameliorated colonic fluid metabolic disorders and visceral sensitization abnormalities, as manifested by increased colonic goblet cell counts and mucin2 protein expression, decreased aquaporin3 protein expression, improved abdominal withdrawal reflex scores, reduced visceral pain threshold, upregulated serum 5-hydroxytryptamine, and downregulated vasoactive intestinal peptide levels. Furthermore, PF activated the colonic ASIC3/ERK pathway in STC rats, and ASIC3 inhibition partially counteracted PF's modulatory effects on intestinal fluid and visceral sensation. In conclusion, PF alleviated impaired intestinal fluid metabolism and abnormal visceral sensitization in STC rats and thus relieved their symptoms through activation of the ASIC3/ERK pathway.


Assuntos
Canais Iônicos Sensíveis a Ácido , Constipação Intestinal , Glucosídeos , Sistema de Sinalização das MAP Quinases , Monoterpenos , Animais , Glucosídeos/farmacologia , Monoterpenos/farmacologia , Monoterpenos/uso terapêutico , Canais Iônicos Sensíveis a Ácido/metabolismo , Constipação Intestinal/tratamento farmacológico , Constipação Intestinal/metabolismo , Ratos , Masculino , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Ratos Sprague-Dawley , Colo/metabolismo , Colo/efeitos dos fármacos , Colo/patologia , Trânsito Gastrointestinal/efeitos dos fármacos , Aquaporina 3/metabolismo , Aquaporina 3/genética , Serotonina/metabolismo , Dor Visceral/tratamento farmacológico , Dor Visceral/metabolismo
17.
Nature ; 629(8013): 851-860, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38560995

RESUMO

Despite tremendous efforts in the past decades, relationships among main avian lineages remain heavily debated without a clear resolution. Discrepancies have been attributed to diversity of species sampled, phylogenetic method and the choice of genomic regions1-3. Here we address these issues by analysing the genomes of 363 bird species4 (218 taxonomic families, 92% of total). Using intergenic regions and coalescent methods, we present a well-supported tree but also a marked degree of discordance. The tree confirms that Neoaves experienced rapid radiation at or near the Cretaceous-Palaeogene boundary. Sufficient loci rather than extensive taxon sampling were more effective in resolving difficult nodes. Remaining recalcitrant nodes involve species that are a challenge to model due to either extreme DNA composition, variable substitution rates, incomplete lineage sorting or complex evolutionary events such as ancient hybridization. Assessment of the effects of different genomic partitions showed high heterogeneity across the genome. We discovered sharp increases in effective population size, substitution rates and relative brain size following the Cretaceous-Palaeogene extinction event, supporting the hypothesis that emerging ecological opportunities catalysed the diversification of modern birds. The resulting phylogenetic estimate offers fresh insights into the rapid radiation of modern birds and provides a taxon-rich backbone tree for future comparative studies.


Assuntos
Aves , Evolução Molecular , Genoma , Filogenia , Animais , Aves/genética , Aves/classificação , Aves/anatomia & histologia , Encéfalo/anatomia & histologia , Extinção Biológica , Genoma/genética , Genômica , Densidade Demográfica , Masculino , Feminino
18.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 32(2): 568-576, 2024 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38660868

RESUMO

OBJECTIVE: To investigate the effect of deacylase Sirtuin 5 in the recovery of hematopoietic stem cells (HSCs) after treated by 5-FU in mouse. METHODS: Flow cytometry was used to analyze the effect of SIRT5 deletion on the proportion of hematopoietic stem/progenitor cells (HSPCs) in bone marrow (BM), the proportion of T cells, B cells and myeloid cells (TBM) in peripheral blood (PB) and spleen, and the development of T cells in thymus. Mouse were treated with 5-FU to study the effect of SIRT5 deletion on the cell cycle, apoptosis and the proportion of HSPCs in BM. The effect of SIRT5 deletion on the proliferation of HSCs was analyzed by flow sorting in vitro. RESULTS: SIRT5 deletion did not affect the development of T cells in thymus and the proportion of TBM cells in PB and spleen compared with wild type mice. SIRT5 deletion increased proportion of HSPCs in BM. After 5-FU treatment, the proportion of HSCs in SIRT5 deletion mice was significant decreased (P < 0.05), the HSPC in SIRT5 deletion mice was activated from G0 to G1 phase (P < 0.05), and the proportion of early apoptosis increased (P < 0.05). By monoclonal culture in vitro, the ability of HSCs to form clones in SIRT5 deletion mice was decreased significantly (P < 0.05). CONCLUSION: SIRT5 deletion lead to a decreased the ability of HSCs to clone in vitro. SIRT5 deletion is not conducive to the recovery of HSPCs injury in mice under hematopoietic stress.


Assuntos
Fluoruracila , Células-Tronco Hematopoéticas , Sirtuínas , Animais , Camundongos , Apoptose , Células da Medula Óssea , Ciclo Celular , Proliferação de Células , Fluoruracila/farmacologia , Sirtuínas/genética , Baço/citologia , Linfócitos T , Timo/citologia
19.
Micromachines (Basel) ; 15(4)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38675345

RESUMO

Soft robots with good deformability and adaptability have important prospects in the bionics and intelligence field. However, current research into soft robots is primarily limited to the study of actuators and ignores the integrated use of functional devices and actuators. To enrich the functions of soft robots and expand their application fields, it is necessary to integrate various functional electronic devices into soft robots to perform diverse functions during dynamic deformation. Therefore, this paper discusses methods and strategies to manufacture optical stimuli-responsive soft actuators and integrate them into functional devices for soft robots. Specifically, laser cutting allows us to fabricate an optically responsive actuator structure, e.g., the curling direction can be controlled by adjusting the direction of the cutting line. Actuators with different bending curvatures, including nonbending, can be obtained by adjusting the cutting depth, cutting width, and the spacing of the cutting line, which makes it easy to obtain a folded structure. Thus, various actuators with complex shape patterns can be obtained. In addition, we demonstrate a fabrication scheme for a worm-like soft robot integrated with functional devices (LEDs are used in this paper). The local nonbending design provides an asymmetric structure that provides driving power and avoids damage to the functional circuit caused by the large deformation during movement. The integration of drive and function provides a new path for the application of soft robots in the intelligence and bionics field.

20.
Adv Mater ; : e2401869, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641342

RESUMO

Smart windows with radiative heat management capability using the sun and outer space as zero-energy thermodynamic resources have gained prominence, demonstrating a minimum carbon footprint. However, realizing on-demand thermal management throughout all seasons while reducing fossil energy consumption remains a formidable challenge. Herein, an energy-efficient smart window that enables actively tunable passive radiative cooling (PRC) and multimode heating regulation is demonstrated by integrating the emission-enhanced polymer-dispersed liquid crystal (SiO2@PRC PDLC) film and a low-emission layer deposited with carbon nanotubes. Specifically, this device can achieve a temperature close to the chamber interior ambient under solar irradiance of 700 W m-2, as well as a temperature drop of 2.3 °C at sunlight of 500 W m-2, whose multistage PRC efficiency can be rapidly adjusted by a moderate voltage. Meanwhile, synchronous cooperation of passive radiative heating (PRH), solar heating (SH), and electric heating (EH) endows this smart window with the capability to handle complicated heating situations during cold weather. Energy simulation reveals the substantial superiority of this device in energy savings compared with single-layer SiO2@PRC PDLC, normal glass, and commercial low-E glass when applied in different climate zones. This work provides a feasible pathway for year-round thermal management, presenting a huge potential in energy-saving applications.

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