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1.
Behav Sci (Basel) ; 14(4)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38667064

RESUMO

The nature of semantic representation has long been a key question in linguistic research. The Embodied Cognition theory challenges the traditional view of language representation, stating that semantic information stems from the sensory-motor cortex, which is activated automatically during semantic processing. However, most of the evidence comes from monolingual studies; it remains unclear whether second-language (L2) comprehension involves different semantic representations or mirrors the pattern seen in first-language (L1) processing. Therefore, the present study investigated the role of the sensory-motor system in language processing via making Electroencephalography (EEG) recordings during the processing of L1 and L2 action verbs. The results showed that L1 (Chinese) action verbs generated higher mu-event-related desynchronization (ERD) than L1 abstract verbs in the early processing stage (250 ms after verb presentation), and the same phenomenon was also observed for L2 (English). The results also indicated that language modulated the processing of action verbs, with L1 action verbs eliciting stronger ERD than L2 action verbs. These results demonstrate that the sensory-motor cortex plays a crucial role in comprehending both L1 and L2 action verbs.

2.
Mar Drugs ; 22(4)2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38667762

RESUMO

Four undescribed sesquiterpenoids, lemneolemnanes A-D (1-4), have been isolated from the marine soft coral Lemnalia sp. The absolute configurations of the stereogenic carbons of 1-4 were determined by single-crystal X-ray crystallographic analysis. Compounds 1 and 2 are epimers at C-3 and have an unusual skeleton with a formyl group on C-6. Compound 3 possesses an uncommonly rearranged carbon skeleton, while 4 has a 6/5/5 tricyclic system. Compound 1 showed significant anti-Alzheimer's disease (AD) activity in a humanized Caenorhabditis elegans AD pathological model.


Assuntos
Antozoários , Caenorhabditis elegans , Sesquiterpenos , Animais , Antozoários/química , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Caenorhabditis elegans/efeitos dos fármacos , Cristalografia por Raios X , Doença de Alzheimer/tratamento farmacológico , Modelos Animais de Doenças , Humanos , Estrutura Molecular
3.
Sci Rep ; 14(1): 7969, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575676

RESUMO

Suppression of threading dislocations (TDs) in thin germanium (Ge) layers grown on silicon (Si) substrates has been critical for realizing high-performance Si-based optoelectronic and electronic devices. An advanced growth strategy is desired to minimize the TD density within a thin Ge buffer layer in Ge-on-Si systems. In this work, we investigate the impact of P dopants in 500-nm thin Ge layers, with doping concentrations from 1 to 50 × 1018 cm-3. The introduction of P dopants has efficiently promoted TD reduction, whose potential mechanism has been explored by comparing it to the well-established Sb-doped Ge-on-Si system. P and Sb dopants reveal different defect-suppression mechanisms in Ge-on-Si samples, inspiring a novel co-doping technique by exploiting the advantages of both dopants. The surface TDD of the Ge buffer has been further reduced by the co-doping technique to the order of 107 cm-2 with a thin Ge layer (of only 500 nm), which could provide a high-quality platform for high-performance Si-based semiconductor devices.

4.
Materials (Basel) ; 17(3)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38591371

RESUMO

By virtue of its narrow pulse width and high peak power, the femtosecond pulsed laser can achieve high-precision material modification, material additive or subtractive, and other forms of processing. With additional good material adaptability and process compatibility, femtosecond laser-induced application has achieved significant progress in flexible electronics in recent years. These advancements in the femtosecond laser fabrication of flexible electronic devices are comprehensively summarized here. This review first briefly introduces the physical mechanism and characteristics of the femtosecond laser fabrication of various electronic microdevices. It then focuses on effective methods of improving processing efficiency, resolution, and size. It further highlights the typical progress of applications, including flexible energy storage devices, nanogenerators, flexible sensors, and detectors, etc. Finally, it discusses the development tendency of ultrashort pulse laser processing. This review should facilitate the precision manufacturing of flexible electronics using a femtosecond laser.

5.
Nutrients ; 16(5)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38474868

RESUMO

BACKGROUND: Healthy diets and physical exercise, two modifiable lifestyle factors, are protective against depression in older adults. This study aimed to investigate whether physical exercise may influence the associations of dietary habits with depression in Chinese community-dwelling older adults. METHODS: In the 2018 wave of the Chinese Longitudinal Healthy Longevity Survey, 12,708 community-dwelling older adults aged ≥65 years were included for analyses. Older adults' dietary habits (including daily intake of food components such as fruits, vegetables, animal oil, and so on) and physical exercise were assessed. Depression was evaluated via the 10 item Center for Epidemiologic Studies Depression (CES-D-10) scale. The influences of physical exercise on the associations of dietary habits with depression were estimated using logistic regression models adjusted for confounders. RESULTS: Older adults who took physical exercise had a significantly decreased probability of depression (adjusted OR = 0.73, p < 0.001). As for dietary habits, the intake of fruits, vegetables, eggs, nut products, mushrooms or algae, and vitamins were inversely associated with the prevalence of depression (adjusted ORs = 0.61-0.81; p-values: from <0.001 to 0.025), while animal oil was positively associated with it (adjusted OR = 1.52, p < 0.001). When stratified by physical exercise, older adults who ate fruits or vegetables had consistent decreased risk of depression, no matter whether they took physical exercise or not (adjusted ORs = 0.52-0.70), while the intake of eggs, nut products, and vitamins were inversely associated, and animal oil was consistently positively associated with depression only in older adults who did not take physical exercise (adjusted ORs = 0.79, 0.68, 0.63, and 1.67, respectively). CONCLUSIONS: Physical exercise may conceal the potential protective effects of some healthy dietary habits in terms of depression and counteract the detrimental effects of the unhealthy habits. Some dietary habits may be considered as alternative protective measures for depression in community-dwelling older adults when physical exercise cannot be performed.


Assuntos
Depressão , Vida Independente , Animais , Estudos Transversais , Depressão/epidemiologia , Dieta , Exercício Físico , Verduras , Vitaminas , Comportamento Alimentar , China
6.
J Sci Food Agric ; 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441143

RESUMO

BACKGROUND: The objective of this investigation was to examine the impact of enzymatic hydrolysis of arabinoxylan (AX) on frozen dough quality under subfreezing conditions. The dough was subjected to freezing at -40 °C for 2 h and then stored at -9, -12, and -18 °C for 15 days. The water loss, freezable water content, water migration, and microstructure of the dough were measured. RESULTS: The dough containing 0.8% cellulase enzymatically hydrolyzed AX (CAX) required the shortest duration when traversing the maximum ice-crystal formation zone (6.5 min). The dough with xylanase enzymatically hydrolyzed AX (XAX) demonstrated a faster freezing rate than the dough with CAX. The inclusion of both XAX and CAX in the dough resulted in the lowest freezable water loss and reduced freezable water content and free-water content levels, whereas the inclusion of xylanase-cellulase combined with enzymatically hydrolyzed AX resulted in higher free-water content levels. The textural properties of the subfreezing temperature dough were not significantly different from the dough stored at -18 °C and sometimes even approached or surpassed the quality observed in the control group rather than the dough stored at -18 °C. In addition, the gluten network structure remains well preserved in XAX- and CAX-containing doughs with minimal starch damage. CONCLUSION: The enzymatic hydrolysis of AX from wheat bran can be used as a useful additive to improve the quality of frozen dough. © 2024 Society of Chemical Industry.

7.
J Cancer Res Clin Oncol ; 150(3): 143, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38504073

RESUMO

OBJECTIVE: To develop and validate a radiomics nomogram based on computed tomography (CT) to distinguish appendiceal mucinous neoplasms (AMNs) from appendicitis with intraluminal fluid (AWIF). METHOD: A total of 211 patients from two medical institutions were retrospectively analysed, of which 109 were pathologically confirmed as having appendicitis with concomitant CT signs of intraluminal fluid and 102 as having AMN. All patients were randomly assigned to a training (147 patients) or validation cohort (64 patients) at a 7:3 ratio. Radiomics features of the cystic fluid area of the appendiceal lesions were extracted from nonenhanced CT images using 3D Slicer software. Minimum redundancy maximum relevance and least absolute shrinkage and selection operator regression methods were employed to screen the radiomics features and develop a radiomics model. Combined radiomics nomogram and clinical-CT models were further developed based on the corresponding features selected after multivariate analysis. Lastly, receiver operating characteristic curves, and decision curve analysis (DCA) were used to assess the models' performances in the training and validation cohorts. RESULTS: A total of 851 radiomics features were acquired from the nonenhanced CT images. Subsequently, a radiomics model consisting of eight selected features was developed. The combined radiomics nomogram model comprised rad-score, age, and mural calcification, while the clinical-CT model contained age and mural calcification. The combined model achieved area under the curves (AUCs) of 0.945 (95% confidence interval [CI]: 0.895, 0.976) and 0.933 (95% CI: 0.841, 0.980) in the training and validation cohorts, respectively, which were larger than those obtained by the radiomics (training cohort: AUC, 0.915 [95% CI: 0.865, 0.964]; validation cohort: AUC, 0.912 [95% CI: 0.843, 0.981]) and clinical-CT models (training cohort: AUC, 0.884 [95% CI: 0.820, 0.931]; validation cohort: AUC, 0.767 [95% CI: 0.644, 0.863]). Finally, DCA showed that the clinical utility of the combined model was superior to that of the clinical CT and radiomics models. CONCLUSION: Our combined radiomics nomogram model constituting radiomics, clinical, and CT features exhibited good performance for differentiating AMN from AWIF, indicating its potential application in clinical decision-making.


Assuntos
Apendicite , Neoplasias Císticas, Mucinosas e Serosas , Neoplasias , Humanos , Apendicite/diagnóstico por imagem , Nomogramas , 60570 , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
8.
Discov Oncol ; 15(1): 66, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38446289

RESUMO

Serum amyloid A1 (SAA1), an inflammation-related molecule, is associated with the malignant progression of many tumors. This study aimed to investigate the role of SAA1 in the progression of esophageal squamous cell carcinoma (ESCC) and its molecular mechanisms. The expression of SAA1 in ESCC tissues and cell lines was analyzed using bioinformatics analysis, western blotting, and reverse transcription-quantitative PCR (RT‒qPCR). SAA1-overexpressing or SAA1-knockdown ESCC cells were used to assess the effects of SAA1 on the proliferation, migration, apoptosis of cancer cells and the growth of xenograft tumors in nude mice. Western blotting, immunofluorescence and RT‒qPCR were used to investigate the relationship between SAA1 and ß-catenin and SAA1 and sphingosine 1-phosphate (S1P)/sphingosine 1-phosphate receptor 1 (S1PR1). SAA1 was highly expressed in ESCC tissues and cell lines. Overexpression of SAA1 significantly promoted the proliferation, migration and the growth of tumors in nude mice. Knockdown of SAA1 had the opposite effects and promoted the apoptosis of ESCC cells. Moreover, SAA1 overexpression promoted the phosphorylation of ß-catenin at Ser675 and increased the expression levels of the ß-catenin target genes MYC and MMP9. Knockdown of SAA1 had the opposite effects. S1P/S1PR1 upregulated SAA1 expression and ß-catenin phosphorylation at Ser675 in ESCC cells. In conclusion, SAA1 promotes the progression of ESCC by increasing ß-catenin phosphorylation at Ser675, and the S1P/S1PR1 pathway plays an important role in its upstream regulation.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38518137

RESUMO

Background: Post-auricular injection of lidocaine and methylprednisolone sodium succinate is a commonly used treatment for outpatient patients with tinnitus, but it is invasive, painful and has uncertain efficacy. We need to try to replace it with more non-invasive and effective treatments. The 2014 guidelines of the American Academy of Otolaryngology-Head and Neck Surgery recommend the use of cognitive behavioral therapy (CBT) to treat tinnitus. Some clinical doctors have also attempted sound therapy for tinnitus. It is unclear whether sound therapy combined with CBT y is more effective than local injection of lidocaine and methylprednisolone sodium succinate in treating tinnitus. Objective: To evaluate the efficacy and influencing factors of refined sound therapy combined with CBT in the treatment of tinnitus and compare it with post-auricular injection of lidocaine and methylprednisolone sodium succinate. Methods: We recruited 100 patients with tinnitus; ultimately, 81 patients completed the experiment and underwent follow-up. Patients were randomly assigned to either the treatment group (refined sound therapy combined with CBT) or the control group (post-auricular injections of lidocaine and methylprednisolone sodium succinate). Data was collected from 49 patients in the treatment group and 32 patients in the control group. Pre- and post-treatment data were collected using the Self-Rating Depression Scale (SDS), Hamilton Anxiety Rating Scale (HAM-A), Visual Analogue Score (VAS), Tinnitus loudness and Tinnitus Handicap Inventory (THI) score. Comparisons between groups were performed using the chi-square test, Fisher's exact test, or Wilcoxon rank-sum test. All tests were two-sided and considered statistically significant with P < .05. Results: The THI, SDS and HAM-A scores in the treatment group decreased significantly. In the control group, there was a significant reduction in THI scores, but not in SDS and HAM-A scores. In addition, tinnitus loudness and VAS scores were significantly decreased in the 2 groups. There was a significant difference in the reduction of THI, SDS, HAM-A and VAS scores between the 2 groups; the treatment group showed a greater reduction. However, there was no significant difference in the reduction of tinnitus loudness. There was no statistical difference in the reduction of THI scores, SDS scores, VAS scores and tinnitus loudness in different frequency groups, but there was a statistical difference in the reduction of HAM-A scores. There was no statistical difference in the reduction of THI scores, SDS scores, HAM-A scores, VAS scores and tinnitus loudness between patients with and without hearing loss. Conclusions: (1) This new combination is more effective than post-auricular injection of lidocaine and methylprednisolone sodium succinate in treating tinnitus and improving psychological symptoms. The latter had no effect on improving psychological indicators. (2) With this combination, patients with different tinnitus frequencies experienced different improvements in anxiety. (3) Low-frequency tinnitus seems have been more likely to cause sound adaptation. (4) The improvement in tinnitus and anxiety was the same regardless of whether or not there was hearing loss.

10.
Small Methods ; : e2400227, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546020

RESUMO

Antimony selenide (Sb2Se3) consists of 1D (Sb4Se6)n ribbons, along which the carriers exhibit high transport efficiency. By adjusting the deposition parameters of vacuum-deposited methods, such as evaporation temperature, chamber pressure, and vapor concentration, it is possible to grow the (Sb4Se6)n ribbons vertically or highly inclined towards the substrate, resulting in films with [hk1] orientation. However, the specific mechanisms by which these deposition parameters affect the orientation of thin films require a deeper understanding. Herein, a molecular beam epitaxy technique is developed for the preparation of highly [hk1]-oriented Sb2Se3 films, and the effect of evaporation parameters on the film orientation is investigated. It is found that the evaporation temperature can affect the decomposition degree of Sb2Se3, which in turn determines the vapor composition and film orientation. Additionally, the decomposition of Sb2Se3 related to evaporation temperature leads to significant changes in the elemental composition of the film, thereby passivating deep-level defects under Se-rich conditions. Consequently, the Sb2Se3 films with highly [hk1] orientation achieve a power conversion efficiency of 8.42% for the solar cells. This study provides new insights into the control of orientation in antimony-based chalcogenide films and points out new directions for improving the photovoltaic performance of solar cells.

11.
Front Pharmacol ; 15: 1336102, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495094

RESUMO

Cardiac fibrosis is a serious health problem because it is a common pathological change in almost all forms of cardiovascular diseases. Cardiac fibrosis is characterized by the transdifferentiation of cardiac fibroblasts (CFs) into cardiac myofibroblasts and the excessive deposition of extracellular matrix (ECM) components produced by activated myofibroblasts, which leads to fibrotic scar formation and subsequent cardiac dysfunction. However, there are currently few effective therapeutic strategies protecting against fibrogenesis. This lack is largely because the molecular mechanisms of cardiac fibrosis remain unclear despite extensive research. The Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling cascade is an extensively present intracellular signal transduction pathway and can regulate a wide range of biological processes, including cell proliferation, migration, differentiation, apoptosis, and immune response. Various upstream mediators such as cytokines, growth factors and hormones can initiate signal transmission via this pathway and play corresponding regulatory roles. STAT3 is a crucial player of the JAK/STAT pathway and its activation is related to inflammation, malignant tumors and autoimmune illnesses. Recently, the JAK/STAT3 signaling has been in the spotlight for its role in the occurrence and development of cardiac fibrosis and its activation can promote the proliferation and activation of CFs and the production of ECM proteins, thus leading to cardiac fibrosis. In this manuscript, we discuss the structure, transactivation and regulation of the JAK/STAT3 signaling pathway and review recent progress on the role of this pathway in cardiac fibrosis. Moreover, we summarize the current challenges and opportunities of targeting the JAK/STAT3 signaling for the treatment of fibrosis. In summary, the information presented in this article is critical for comprehending the role of the JAK/STAT3 pathway in cardiac fibrosis, and will also contribute to future research aimed at the development of effective anti-fibrotic therapeutic strategies targeting the JAK/STAT3 signaling.

12.
Front Endocrinol (Lausanne) ; 15: 1291895, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38419954

RESUMO

Introduction: The ratio of Triglyceride (TG) to high-density lipoprotein cholesterol (HDL-C) is a crucial indicator for diabetes diagnosis. Methods: This study utilizes the Copula function to model and fit the non-linear correlation among fasting blood glucose (Glu), glycosylated hemoglobin (HbA1C), and TG/HDL-C in patients with diabetes. The Copula function chosen for this study includes the two-dimensional Archimedes and Elliptical distribution family, as well as the multidimensional Vine Copula function, for fitting the data. The evaluation of the fitting effect is performed using the mean absolute error (MAE) and mean square error (MSE). Results: The results indicate that the Clayton Copula exhibits the highest effectiveness in fitting the pairwise relationship between Glu and TG/HDL-C, as well as HbA1C and TG/HDL-C, displaying the smallest fitting error. Additionally, the Vine Copula function produces a satisfactory fit for the relationship among all three indicators. Compared to linear analysis methods, the Copula function more accurately depicts the correlation among these three types of indicators. Discussion: Moreover, our findings indicate a stronger correlation in the lower tail between Glu and HbA1C, as well as TG/HDL-C, suggesting that the Copula function provides greater accuracy and applicability in depicting the relationship among these indicators. As a result, it can offer a more precise auxiliary diagnosis and serve as a valuable reference in clinical judgment.


Assuntos
Glicemia , Diabetes Mellitus , Humanos , Hemoglobinas Glicadas , Diabetes Mellitus/diagnóstico , Triglicerídeos , HDL-Colesterol
13.
ACS Omega ; 9(4): 4931-4948, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38313483

RESUMO

Pneumatic conveying devices are commonly used in the fields of chemical industry, raw material transportation, and material processing. Elongated biomass particles are not evenly distributed in the lifting tube because biomass clumps during conveying. Pneumatic conveying test setup and measurement system were built in this paper in order to study the agglomeration behavior of elongated biomass particles in the lifting tube experimentally. Particle tracking velocimetry (PTV) was used to determine the area distribution and velocity distribution of particles at different apparent air velocities and mass flow rates. The results show that while keeping the mass flow rate constant at 46.50 g/s, the apparent gas velocity increased from 5.91 to 7.91 m/s and the maximum size of agglomerates decreased from 0.689 to 0.235. The apparent gas velocity was kept at 6.40 m/s, and the particle mass flow rate was adjusted from 56.50 to 16.20 g/s. The maximum size of the agglomerates was reduced to 0.115. Therefore, appropriately increasing the apparent gas velocity or decreasing the particle mass flow rate can improve the uniformity of the particle distribution in the lifting tube. The results would provide a reference for parameter adjustment of pneumatic conveying devices in industrial production.

14.
Toxicol Res (Camb) ; 13(1): tfae022, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38419835

RESUMO

Background: Fine particulate matter (PM2.5) exposure has been closely associated with cardiovascular diseases, which are relevant to cell cycle arrest. Brain and muscle aryl-hydrocarbon receptor nuclear translocator-like protein 1 (BMAL1) not only participates in regulating the circadian clock but also plays a role in modulating cell cycle. However, the precise contribution of the circadian clock gene BMAL1 to PM2.5-induced cell cycle change remains unclear. This study aims to explore the impact of PM2.5 exposure on BMAL1 expression and the cell cycle in human umbilical vein endothelial cells (HUVECs). Methods: HUVECs was exposed to PM2.5 for 24 hours at different concentrations ((0, 12.5, 25, 75 and 100 µg.mL-1) to elucidate the potential toxic mechanism. Following exposure to PM2.5, cell viability, ROS, cell cycle, and the expression of key genes and proteins were detected. Results: A remarkable decrease in cell viability is observed in the PM2.5-exposed HUVECs, as well as a significant increase in ROS production. In addition, PM2.5-exposed HUVECs have cycle arrest in G0/G1 phase, and the gene expression of p27 is also markedly increased. The protein expression of BMAL1 and the gene expression of BMAL1 are increased significantly. Moreover, the protein expressions of p-p38 MAPK and p-ERK1/2 exhibit a marked increase in the PM2.5-exposed HUVECs. Furthermore, following the transfection of HUVECs with siBMAL1 to suppress BMAL1 expression, we observed a reduction in both the protein and gene expression of the MAPK/ERK pathway in HUVECs exposed to PM2.5. Conclusions: Overall, our results indicate that PM2.5 exposure significantly upregulates the circadian clock gene expression of BMAL1 and regulates G0/G1 cell cycle arrest in HUVECs through the MAPK/ERK pathway, which may provide new insights into the potential molecular mechanism regarding BMAL1 on PM2.5-induced cardiovascular diseases.

15.
Brain Sci ; 14(2)2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38391744

RESUMO

Recent research suggests a possible association between midlife obesity and an increased risk of dementia in later life. However, the underlying mechanisms remain unclear. Little is known about the relationship between body mass index (BMI) and hippocampal subfield atrophy. In this study, we aimed to explore the associations between BMI and hippocampal subfield volumes and cognitive function in non-demented Chinese older adults. Hippocampal volumes were assessed using structural magnetic resonance imaging. Cognitive function was evaluated using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). A total of 66 participants were included in the final analysis, with 35 females and 31 males. We observed a significant correlation between BMI and the hippocampal fissure volume in older females. In addition, there was a negative association between BMI and the RBANS total scale score, the coding score, and the story recall score, whereas no significant correlations were observed in older males. In conclusion, our findings revealed sex-specific associations between BMI and hippocampal subfield volumes and cognitive performance, providing valuable insights into the development of effective interventions for the early prevention of cognitive decline.

16.
Sci China Life Sci ; 67(4): 778-788, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38212459

RESUMO

Anthropogenic environmental changes may affect community assembly through mediating both deterministic (e.g., competitive exclusion and environmental filtering) and stochastic processes (e.g., birth/death and dispersal/colonization). It is traditionally thought that environmental changes have a larger mediation effect on stochastic processes in structuring soil microbial community than aboveground plant community; however, this hypothesis remains largely untested. Here we report an unexpected pattern that nitrogen (N) deposition has a larger mediation effect on stochastic processes in structuring plant community than soil microbial community (those <2 mm in diameter, including archaea, bacteria, fungi, and protists) in the Eurasian steppe. We performed a ten-year nitrogen deposition experiment in a semiarid grassland ecosystem in Inner Mongolia, manipulating nine rates (0-50 g N m-2 per year) at two frequencies (nitrogen added twice or 12 times per year) under two grassland management strategies (fencing or mowing). We separated the compositional variation of plant and soil microbial communities caused by each treatment into the deterministic and stochastic components with a recently-developed method. As nitrogen addition rate increased, the relative importance of stochastic component of plant community first increased and then decreased, while that of soil microbial community first decreased and then increased. On the whole, the relative importance of stochastic component was significantly larger in plant community (0.552±0.035; mean±standard error) than in microbial community (0.427±0.035). Consistently, the proportion of compositional variation explained by the deterministic soil and community indices was smaller for plant community (0.172-0.186) than microbial community (0.240-0.767). Meanwhile, as nitrogen addition rate increased, the linkage between plant and microbial community composition first became weaker and then became stronger. The larger stochasticity in plant community relative to microbial community assembly suggested that more stochastic strategies (e.g., seeds addition) should be adopted to maintain above- than below-ground biodiversity under the pressure of nitrogen deposition.


Assuntos
Microbiota , Solo , Ecossistema , Nitrogênio/análise , Microbiologia do Solo , Plantas/microbiologia , Processos Estocásticos
17.
Org Lett ; 26(2): 477-482, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38194611

RESUMO

A palladium/norbornene catalyzed two-component coupling process involving acylation/cyanation of aryl iodides is reported. In this work, aryl acyl nitrile compounds are cleverly selected to provide both nitrile and acyl sources by palladium-catalyzed cleavage of the C-CN bond as both an electrophilic reagent and a termination reagent. This is the first example of C-CN bond cleavage bifunctionalization of aryl iodides. After a series of important NBE derivatives are screened, the products resulting from the bifunctionalization of aryl iodides are smoothly obtained. This strategy has a wide range of substrates and good functional group compatibility. Moreover, this synthetic protocol demonstrated a good application for the synthesis of diverse O,N,C-substituted isoindolinones.

18.
Materials (Basel) ; 17(2)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38255556

RESUMO

In order to realize the resource utilization of solid waste and improve the tensile strength and toughness of soil, CCR-GGBS-FA all-solid-waste binder (CGF) composed of general industrial solid waste calcium carbide residue (CCR), ground granulated blast furnace slag (GGBS) and fly ash (FA) was used instead of cement and combined with polypropylene fiber to strengthen the silty soil taken from Dongying City, China. An unconfined compressive strength test (UCS test) and a uniaxial tensile test (UT test) were carried out on 10 groups of samples with five different fiber contents to uncover the effect of fiber content on tensile and compressive properties, and the reinforcement mechanism was studied using a scanning electron microscopy (SEM) test. The test results show that the unconfined compressive strength, the uniaxial tensile strength, the deformation modulus, the tensile modulus, the fracture energy and the residual strength of fiber-reinforced CGF-solidified soil are significantly improved compared with nonfiber-solidified soil. The compressive strength and the tensile strength of polypropylene-fiber-reinforced CGF-solidified soil reach the maximum value when the fiber content is 0.25%, as the unconfined compressive strength and the tensile strength are 3985.7 kPa and 905.9 kPa, respectively, which are 116.60% and 186.16% higher than those of nonfiber-solidified soil, respectively. The macro-micro tests identify that the hydration products generated by CGF improve the compactness through gelling and filling in solidified soil, and the fiber enhances the resistance to deformation by bridging and forming a three-dimensional network structure. The addition of fiber effectively improves the toughness and stiffness of solidified soil and makes the failure mode of CGF-solidified soil transition from typical brittle failure to plastic failure. The research results can provide a theoretical basis for the application of fiber-reinforced CGF-solidified soil in practical engineering.

19.
Funct Integr Genomics ; 24(1): 12, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38228798

RESUMO

Promoter methylation is one of the most studied epigenetic modifications and it is highly relevant to the onset and progression of thyroid carcinoma (THCA). This study investigates the promoter methylation and expression pattern of intercellular adhesion molecule 5 (ICAM5) in THCA. CpG islands with aberrant methylation pattern in THCA, and the expression profiles of the corresponding genes in THCA, were analyzed using bioinformatics. ICAM5 was suggested to have a hypermethylation status, and it was highly expressed in THCA tissues and cells. Its overexpression promoted proliferation, mobility, and tumorigenic activity of THCA cells. As for the downstream signaling, ICAM5 was found to activate the MAPK/ERK and MAPK/JNK signaling pathways. Either inhibition of ERK or JNK blocked the oncogenic effects of ICAM5. DNA methyltransferases 1 (DNMT1) and DNMT3a were found to induce promoter hypermethylation of ICAM5 in THCA cells. Knockdown of DNMT1 or DNMT3a decreased the ICAM5 expression and suppressed malignant properties of THCA cells in vitro and in vivo, which were, however, restored by further artificial ICAM5 overexpression. Collectively, this study reveals that DNMT1 and DNMT3a mediates promoter hypermethylation and transcription activation of ICAM5 in THCA, which promotes malignant progression of THCA through the MAPK signaling pathway.


Assuntos
DNA (Citosina-5-)-Metiltransferases , Neoplasias da Glândula Tireoide , Humanos , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Ativação Transcricional , Metilação de DNA , Neoplasias da Glândula Tireoide/genética , Proteínas do Tecido Nervoso/genética , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo
20.
Adv Mater ; 36(1): e2305841, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37947249

RESUMO

Sb2 S3 is a promising environmentally friendly semiconductor for high performance solar cells. But, like many other polycrystalline materials, Sb2 S3 is limited by nonradiative recombination and carrier scattering by grain boundaries (GBs). This work shows how the GB density in Sb2 S3 films can be significantly reduced from 1068 ± 40 to 327 ± 23 nm µm-2 by incorporating an appropriate amount of Ce3+ into the precursor solution for Sb2 S3 deposition. Through extensive characterization of structural, morphological, and optoelectronic properties, complemented with computations, it is revealed that a critical factor is the formation of an ultrathin Ce2 S3 layer at the CdS/Sb2 S3 interface, which can reduce the interfacial energy and increase the adhesion work between Sb2 S3 and the substrate to encourage heterogeneous nucleation of Sb2 S3 , as well as promote lateral grain growth. Through reductions in nonradiative recombination at GBs and/or the CdS/Sb2 S3 heterointerface, as well as improved charge-carrier transport properties at the heterojunction, this work achieves high performance Sb2 S3 solar cells with a power conversion efficiency reaching 7.66%. An impressive open-circuit voltage (VOC ) of 796 mV is achieved, which is the highest reported thus far for Sb2 S3 solar cells. This work provides a strategy to simultaneously regulate the nucleation and growth of Sb2 S3 absorber films for enhanced device performance.

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