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1.
Plant Commun ; : 100934, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689493

RESUMO

In angiosperms, the pollen tube enters the receptive synergid cell, where they rupture to release its cytoplasm along with two sperm cells. Although this interaction is complex, the exact signal transducers that trigger the bursting of pollen tubes are not well understood. In this study, we identify three homologous Receptor-Like Cytoplasmic Kinase (RLCK) expressed in pollen tubes, named Delayed Burst 1/2/3 (DEB1/2/3) in Arabidopsis, which play a crucial role in this process. These genes produce proteins localized on the plasma membrane, and knockout of them causes delayed pollen tube burst and the entrance of additional pollen tubes into the embryo sac due to fertilization recovery. We show that DEBs interact with the Ca2+ pump ACA9, influencing the dynamics of cytoplasmic Ca2+ in pollen tubes through phosphorylation. These results highlight the importance of DEBs as key signal transducers and the critical function of the DEB-ACA9 axis in the timely pollen tube burst in synergids.

2.
Food Chem ; 451: 139505, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38703732

RESUMO

Constructing carrier materials with polysaccharides to enhance the solubility of insoluble active ingredients is a crucial strategy for improving bioavailability. This research constructed pectin-based hesperidin microcapsules (PHM) through self-assembly processes in the deep eutectic solvent, improving the solubility, storage stability, and bioavailability of hesperidin (HES). PHM exhibited high encapsulation efficiency (91.7%) and loading capacity (11.5%), with a small particle size (1.73 µm). The interaction mechanism was clarified through physical characterization and density functional theory (DFT) calculations. The vitro release demonstrated that the release ratio of PHM was only 6.4% in simulated gastric fluid (SGF), but reached 80.9% in simulated intestinal fluid (SIF). The release mechanism of PHM in SGF followed Fickian diffusion, while in SIF followed skeleton dissolution diffusion with a stable rate. Furthermore, the cell cytotoxicity experiments confirmed the remarkable biocompatibility of PHM toward human colon cells, which suggested its potential application in food and pharmaceutical fields.


Assuntos
Cápsulas , Hesperidina , Pectinas , Solubilidade , Pectinas/química , Hesperidina/química , Humanos , Cápsulas/química , Portadores de Fármacos/química , Tamanho da Partícula , Composição de Medicamentos , Disponibilidade Biológica , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Sobrevivência Celular/efeitos dos fármacos , Células CACO-2
3.
J Neuroimmunol ; 391: 578367, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38735091

RESUMO

BACKGROUND: Sepsis-associated encephalopathy (SAE) presents a significant clinical challenge, associated with increased mortality and healthcare expenses. Hyperbaric oxygen therapy (HBOT), involving inhaling pure or highly concentrated oxygen under pressures exceeding one atmosphere, has demonstrated neuroprotective effects in various conditions. However, the precise mechanisms underlying its protective actions against sepsis-associated brain injury remain unclear. This study aimed to determine whether HBOT protects against SAE and to elucidate the impact of the hypoxia-inducible factor-1α (HIF-1α) signaling pathway on SAE. METHODS: The experiment consisted of two parts. In the first part, C57BL/6 J male mice were divided into five groups using a random number table method: control group, sham surgery group, sepsis group, HBOT + sepsis group, and HBOT + sham surgery group. In the subsequent part, C57BL/6 J male mice were divided into four groups: sepsis group, HBOT + sepsis group, HIF-1α + HBOT + sepsis group, and HIF-1α + sepsis group. Sepsis was induced via cecal ligation and puncture (CLP). Hyperbaric oxygen therapy was administered at 1 h and 4 h post-CLP. After 24 h, blood and hippocampal tissue were collected for cytokine measurements. HIF-1α, TNF-α, IL-1ß, and IL-6 expression were assessed via ELISA and western blotting. Microglial expression was determined by immunofluorescence. Blood-brain barrier permeability was quantified using Evans Blue. Barnes maze and fear conditioning were conducted 14 days post-CLP to evaluate learning and memory. RESULTS: Our findings reveal that CLP-induced hippocampus-dependent cognitive deficits coincided with elevated HIF-1α and increased TNF-α, IL-1ß, and IL-6 levels in both blood and hippocampus. Observable activation of microglial cells in the hippocampus and increased blood-brain barrier (BBB) permeability were also evident. HBOT mitigated HIF-1α, TNF-α, IL-1ß, and IL-6 levels, attenuated microglial activation in the hippocampus, and significantly improved learning and memory deficits in CLP-exposed mice. Additionally, these outcomes were corroborated by injecting a lentivirus that overexpressed HIF-1α into the hippocampal region of the mice. CONCLUSION: HIF-1α escalation induced peripheral and central inflammatory factors, promoting microglial activation, BBB impairment, and cognitive dysfunction. However, HBOT ameliorated these effects by reducing HIF-1α levels in Sepsis-Associated Encephalopathy.

4.
Braz J Med Biol Res ; 57: e13389, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38716983

RESUMO

During the COVID-19 outbreak, there was a sharp increase in generalized anxiety disorder (GAD). Acupuncture therapy has the advantages of accurate clinical efficacy, safety and reliability, few adverse reactions, and no dependence, and is gradually becoming one of the emerging therapies for treating GAD. We present a study protocol for a randomized clinical trial with the aim of exploring the mechanism of brain plasticity in patients with GAD and evaluate the effectiveness and reliability of acupuncture treatment. Transcranial magnetic stimulation (TMS) will be used to assess cortical excitability in GAD patients and healthy people. Sixty-six GAD patients meeting the inclusion criteria will be randomly divided into two groups: TA group, (treatment with acupuncture and basic western medicine treatment) and SA group (sham acupuncture and basic western medicine treatment). Twenty healthy people will be recruited as the control group (HC). The parameters that will be evaluated are amplitude of motor evoked potentials (MEPs), cortical resting period (CSP), resting motor threshold (RMT), and Hamilton Anxiety Scale (HAMA) score. Secondary results will include blood analysis of γ-aminobutyric acid (GABA), glutamate (Glu), glutamine (Gln), serotonin (5-HT), and brain-derived nerve growth factor (BDNF). Outcomes will be assessed at baseline and after the intervention (week 8). This study protocol is the first clinical trial designed to detect differences in cerebral cortical excitability between healthy subjects and patients with GAD, and the comparison of clinical efficacy and reliability before and after acupuncture intervention is also one of the main contents of the protocol. We hope to find a suitable non-pharmacological alternative treatment for patients with GAD.


Assuntos
Terapia por Acupuntura , Transtornos de Ansiedade , COVID-19 , Estimulação Magnética Transcraniana , Humanos , Terapia por Acupuntura/métodos , Transtornos de Ansiedade/terapia , Estimulação Magnética Transcraniana/métodos , COVID-19/terapia , Adulto , Masculino , Feminino , Potencial Evocado Motor/fisiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Reprodutibilidade dos Testes , SARS-CoV-2 , Pessoa de Meia-Idade , Adulto Jovem
6.
ISA Trans ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38797650

RESUMO

BACKGROUND: The manipulation of compliant objects by robotic systems remains a challenging task, largely due to their variable shapes and the complex, high-dimensional nature of their interaction dynamics. Traditional robotic manipulation strategies struggle with the accurate modeling and control necessary to handle such materials, especially in the presence of visual occlusions that frequently occur in dynamic environments. Meanwhile, for most unstructured environments, robots are required to have autonomous interactions with their surroundings. METHODS: To solve the shape manipulation of compliant objects in an unstructured environment, we begin by exploring the regression-based algorithm of representing the high-dimensional configuration space of deformable objects in a compressed form that enables efficient and effective manipulation. Simultaneously, we address the issue of visual occlusions by proposing the integration of an adversarial network, enabling guiding the shaping task even with partial observations of the object. Afterwards, we propose a receding-time estimator to coordinate the robot action with the computed shape features while satisfying various performance criteria. Finally, model predictive controller is utilized to compute the robot's shaping motions subject to safety constraints. Detailed experiments are presented to evaluate the proposed manipulation framework. SIGNIFICANT FINDINGS: Our MPC framework utilizes the compressed representation and occlusion-compensated information to predict the object's behavior, while the multi-objective optimizer ensures that the resulting control actions meet multiple performance criteria. Through rigorous experimental validation, our approach demonstrates superior manipulation capabilities in scenarios with visual obstructions, outperforming existing methods in terms of precision and operational reliability. The findings highlight the potential of our integrated approach to significantly enhance the manipulation of compliant objects in real-world robotic applications.

7.
Front Big Data ; 7: 1353469, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38817683

RESUMO

Objective: To develop a robust machine learning prediction model for the automatic screening and diagnosis of obstructive sleep apnea (OSA) using five advanced algorithms, namely Extreme Gradient Boosting (XGBoost), Logistic Regression (LR), Support Vector Machine (SVM), Light Gradient Boosting Machine (LightGBM), and Random Forest (RF) to provide substantial support for early clinical diagnosis and intervention. Methods: We conducted a retrospective analysis of clinical data from 439 patients who underwent polysomnography at the Affiliated Hospital of Xuzhou Medical University between October 2019 and October 2022. Predictor variables such as demographic information [age, sex, height, weight, body mass index (BMI)], medical history, and Epworth Sleepiness Scale (ESS) were used. Univariate analysis was used to identify variables with significant differences, and the dataset was then divided into training and validation sets in a 4:1 ratio. The training set was established to predict OSA severity grading. The validation set was used to assess model performance using the area under the curve (AUC). Additionally, a separate analysis was conducted, categorizing the normal population as one group and patients with moderate-to-severe OSA as another. The same univariate analysis was applied, and the dataset was divided into training and validation sets in a 4:1 ratio. The training set was used to build a prediction model for screening moderate-to-severe OSA, while the validation set was used to verify the model's performance. Results: Among the four groups, the LightGBM model outperformed others, with the top five feature importance rankings of ESS total score, BMI, sex, hypertension, and gastroesophageal reflux (GERD), where Age, ESS total score and BMI played the most significant roles. In the dichotomous model, RF is the best performer of the five models respectively. The top five ranked feature importance of the best-performing RF models were ESS total score, BMI, GERD, age and Dry mouth, with ESS total score and BMI being particularly pivotal. Conclusion: Machine learning-based prediction models for OSA disease grading and screening prove instrumental in the early identification of patients with moderate-to-severe OSA, revealing pertinent risk factors and facilitating timely interventions to counter pathological changes induced by OSA. Notably, ESS total score and BMI emerge as the most critical features for predicting OSA, emphasizing their significance in clinical assessments. The dataset will be publicly available on my Github.

9.
Colloids Surf B Biointerfaces ; 239: 113939, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38744077

RESUMO

Chronic infections caused by the pathogenic biofilms on implantable medical devices pose an increasing challenge. To combat long-term biofilm-associated infections, we developed a novel dual-functional polymer coating with antibacterial and antifouling properties. The coating consists of N-vinylpyrrolidone (NVP) and 3-(acrylamido)phenylboronic acid (APBA) copolymer brushes, which bind to curcumin (Cur) as antibacterial molecules through acid-responsive boronate ester bonds. In this surface design, the hydrophilic poly (N-vinylpyrrolidone) (PVP) component improved antifouling performance and effectively prevented bacterial adhesion and aggregation during the initial phases. The poly (3-(acrylamido) phenylboronic acid) (PAPBA, abbreviated PB) component provided binding sites for Cur by forming acid-responsive boronate ester bonds. When fewer bacteria overcame the anti-adhesion barrier and colonized, the surface responded to the decreased microenvironmental pH by breaking the boronate ester bonds and releasing curcumin. This responsive mechanism enabled Cur to interfere with biofilm formation and provide a multilayer anti-biofilm protection system. The coating showed excellent antibacterial properties against Escherichia coli and Staphylococcus aureus, preventing biofilm formation for up to 7 days. The coating also inhibited protein adsorption and platelet adhesion significantly. This coating also exhibited high biocompatibility with animal erythrocytes and pre-osteoblasts. This research offers a promising approach for developing novel smart anti-biofilm coating materials.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38764086

RESUMO

It is important to explore the characteristics and rules of atmospheric aerosol in the East Asian Sea for monitoring and evaluating atmospheric environmental quality. Based on Aerosol Robot Network (AERONET), Visible Infrared Imaging Radiometer (VIIRS), and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data, the temporal and spatial variation characteristics and differences of aerosol parameters and types in the East Asian Sea were studied by using figure classification method (FIGCM), aerosol optical depth (AOD)440-Angstrom exponent (AE)440-870 method (AA1M), and AOD550-AE490-670 method (AA2M). The results show that the seasonal variation trend of aerosol characteristics and types is obvious in East Asia Sea. AOD, volume concentration (Cv), and aerosol effective radius (reff) in the Bohai-Yellow Sea and the Sea of Japan in autumn are lower than those in other seasons, and the occurrence frequency of ocean-type aerosols is high. Different from the Bohai-Yellow Sea and Sea of Japan, human activities in winter, summer, and autumn seriously affect the air quality in the East China Sea and South China Sea. Especially at the Taipei CWB site, from aerosol parameters and high biomass burning/urban industrial (BB/UI) aerosol, human activity is an important factor for high pollution at the Taipei CWB site. Aerosol types of AA1M, FIGCM, AA2M, and CALIPSO were compared at Anmyon and Yonsei University sites in the Bohai-Yellow Sea in March 2020. The results show that aerosol types based on threshold classification methods generally have higher mixed aerosol results, and the marine (MA) results of AA1M, FIGCM, and AA2M are close to the clean marine aerosol results of CALIPSO. Comparing the results of AA 2 M and CALIPSO on a spatial scale, it is found that the clean marine aerosol proportion identified by CALIPSO (0.38, 0.48, 0.82) is consistent with the MA proportion identified by AA 2 M (0.43, 0.46, 0.97) in the East China Sea, South China Sea, and Western Pacific Ocean.

11.
J Hazard Mater ; 473: 134610, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38776812

RESUMO

Mg-K homeostasis is essential for plant response to abiotic stress, but its regulation remains largely unknown. MsWRKY44 cloned from alfalfa was highly expressed in leaves and petioles. Overexpression of it inhibited alfalfa growth, and promoted leaf senescence and alfalfa sensitivities to acid and Al stresses. The leaf tips, margins and interveins of old leaves occurred yellow spots in MsWRKY44-OE plants under pH4.5 and pH4.5 +Al conditions. Meanwhile, Mg-K homeostasis was substantially changed with reduction of K accumulation and increases of Mg as well as Al accumulation in shoots of MsWRKY44-OE plants. Further, MsWRKY44 was found to directly bind to the promoters of MsMGT7 and MsCIPK23, and positively activated their expression. Transiently overexpressed MsMGT7 and MsCIPK23 in tobacco leaves increased the Mg and Al accumulations but decreased K accumulation. These results revealed a novel regulatory module MsWRKY44-MsMGT7/MsCIPK23, which affects the transport and accumulation of Mg and K in shoots, and promotes alfalfa sensitivities to acid and Al stresses.

12.
Comput Methods Programs Biomed ; 252: 108233, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38781810

RESUMO

BACKGROUND AND OBJECTIVE: Music, the ubiquitous language across human cultures, is traditionally considered as a form of art but has been linked to biomolecules in recent years. However, previous efforts have only been addressed on sonification of nucleic acids and proteins to produce so-called life music, the soundscape from the basic building blocks of life. In this study, we attempted to, for the first time, conduct a reverse operation of this process, i.e. conversion of music to protein (CoMtP). METHODS: A novel notion termed musical protein (MP) -- the protein defined by music -- was proposed and, on this basis, we described a computational strategy to map the time sequence of music onto the spatial architecture of proteins, which considered that each note in the stave of a music (target) can be simply characterized by two acoustical quantities and that each residue in the primary sequence of a protein (hit) was represented by amino acid descriptors. RESULTS: A simulated annealing (SA) algorithm was applied to iteratively generate the best matched MP hit for a music target and structural bioinformatics was then used to model spatial advanced structure for the resulting MP. We also demonstrated that some small MPs derived from music segments may have potential biological functions, which, for example, can serve as antimicrobial peptides (AMPs) to inhibit clinical bacterial strains with moderate or high antibacterial potency. CONCLUSIONS: This work may benefit many aspects; for example, it would open a door for the hearing-impaired persons to 'listen' music in a biological vision and could be a mean of exposing students to the concepts of biomolecules at an earlier age through the use of auditory characteristics. The CoMtP would also facilitate the rational design of proteins with biological and medicinal significance.

13.
Pediatr Rheumatol Online J ; 22(1): 58, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783316

RESUMO

BACKGROUND: Macrophage activation syndrome (MAS), an example of secondary hemophagocytic lymphohistiocytosis, is a potentially fatal complication of rheumatic diseases. We aimed to study the clinical and laboratory characteristics, treatment schemes, and outcomes of different rheumatic disorders associated with MAS in children. Early warning indicators of MAS have also been investigated to enable clinicians to make a prompt and accurate diagnosis. METHODS: Fifty-five patients with rheumatic diseases complicated by MAS were enrolled between January 2017 and December 2022. Clinical and laboratory data were collected before disease onset, at diagnosis, and after treatment with MAS, and data were compared between patients with systemic juvenile idiopathic arthritis (sJIA), Kawasaki disease (KD), and systemic lupus erythematosus (SLE). A random forest model was established to show the importance score of each variable with a significant difference. RESULTS: Most (81.8%) instances of MAS occurred during the initial diagnosis of the underlying disease. Compared to the active stage of sJIA, the platelet count, erythrocyte sedimentation rate, and fibrinogen level in sJIA-MAS were significantly decreased, whereas ferritin, ferritin/erythrocyte sedimentation rate, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and D-dimer levels were significantly increased. Ferritin level, ferritin/erythrocyte sedimentation rate, and platelet count had the greatest predictive value for sJIA-MAS. The level of IL-18 in the sJIA-MAS group was significantly higher than in the active sJIA group, whereas IL-6 levels were significantly lower. Most patients with MAS were treated with methylprednisolone pulse combined with cyclosporine, and no deaths occurred. CONCLUSIONS: Thrombocytopenia, ferritin levels, the ferritin/erythrocyte sedimentation rate, and elevated aspartate aminotransferase levels can predict the occurrence of MAS in patients with sJIA. Additionally, our analysis indicates that IL-18 plays an important role in the pathogenesis of MAS in sJIA-MAS.


Assuntos
Artrite Juvenil , Síndrome de Ativação Macrofágica , Humanos , Síndrome de Ativação Macrofágica/etiologia , Síndrome de Ativação Macrofágica/diagnóstico , Masculino , Feminino , Criança , Artrite Juvenil/complicações , Pré-Escolar , Adolescente , Ferritinas/sangue , Lúpus Eritematoso Sistêmico/complicações , Sedimentação Sanguínea , Estudos Retrospectivos , Contagem de Plaquetas , Síndrome de Linfonodos Mucocutâneos/complicações , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Síndrome de Linfonodos Mucocutâneos/sangue
14.
Compr Rev Food Sci Food Saf ; 23(3): e13368, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38720574

RESUMO

Spoilage and deterioration of aquatic products during storage are inevitable, posing significant challenges to their suitability for consumption and the sustainability of the aquatic products supply chain. Research on the nonthermal processing of fruit juices, probiotics, dairy products, and meat has demonstrated positive outcomes in preserving quality. This review examines specific spoilage bacteria species and mechanisms for various aquatic products and discusses the principles, characteristics, and applications of six nonthermal processing methods for bacterial inhibition to maintain microbiological safety and physicochemical quality. The primary spoilage bacteria groups differ among fish, crustaceans, and shellfish based on storage conditions and durations. Four metabolic pathways utilized by spoilage microorganisms-peptides and amino acids, nitrogen compounds, nucleotides, and carbohydrates-are crucial in explaining spoilage. Nonthermal processing techniques, such as ultrahigh pressure, irradiation, magnetic/electric fields, plasma, and ultrasound, can inactivate microorganisms, thereby enhancing microbiological safety, physicochemical quality, and shelf life. Future research may integrate nonthermal processing with other technologies (e.g., modified atmosphere packaging and omics) to elucidate mechanisms of spoilage and improve the storage quality of aquatic products.


Assuntos
Manipulação de Alimentos , Microbiologia de Alimentos , Animais , Manipulação de Alimentos/métodos , Conservação de Alimentos/métodos , Inocuidade dos Alimentos/métodos , Alimentos Marinhos/microbiologia , Alimentos Marinhos/normas , Bactérias , Frutos do Mar/microbiologia , Frutos do Mar/normas , Laticínios/microbiologia , Laticínios/normas , Probióticos , Peixes/microbiologia
15.
J Agric Food Chem ; 72(19): 11268-11277, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38695399

RESUMO

Buttermilk is a potential material for the production of a milk fat globule membrane (MFGM) and can be mainly classified into two types: whole cream buttermilk and cheese whey cream buttermilk (WCB). Due to the high casein micelle content of whole cream buttermilk, the removal of casein micelles to improve the purity of MFGM materials is always required. This study investigated the effects of rennet and acid coagulation on the lipid profile of buttermilk rennet-coagulated whey (BRW) and buttermilk acid-coagulated whey (BAW) and compared them with WCB. BRW has significantly higher phospholipids (PLs) and ganglioside contents than BAW and WCB. The abundance of arachidonic acid (ARA)- and eicosapentaenoic acid (EPA)-structured PLs was higher in WCB, while docosahexaenoic acid (DHA)-structured PLs were higher in BRW, indicating that BRW and WCB intake might have a greater effect on improving cardiovascular conditions and neurodevelopment. WCB and BRW had a higher abundance of plasmanyl PL and plasmalogen PL, respectively. Phosphatidylcholine (PC) (28:1), LPE (20:5), and PC (26:0) are characteristic lipids among BRW, BAW, and WCB, and they can be used to distinguish MFGM-enriched whey from different sources.


Assuntos
Leitelho , Queijo , Cabras , Lipidômica , Soro do Leite , Animais , Leitelho/análise , Queijo/análise , Soro do Leite/química , Fosfolipídeos/análise , Fosfolipídeos/química , Glicolipídeos/química , Leite/química , Gotículas Lipídicas/química , Glicoproteínas/química , Glicoproteínas/análise , Lipídeos/química , Lipídeos/análise
16.
J Psycholinguist Res ; 53(3): 46, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38744739

RESUMO

Wh-words have been analysed as existential quantifiers (Chierchia in Logic in grammar: polarity, free choice, and intervention. Oxford University Press, Oxford, 2013; Fox, in Sauerland U, Stateva P (eds) Presupposition and implicature in compositional semantics (Palgrave studies in pragmatics, language and cognition). Palgrave MacMillan, Houndmills, pp 71-120, 2007; Liao in Alternative and exhaustification: non-interrogative uses of Chinese wh-words. Harvard University, 2010) or universal quantifiers (Nishigauchi, in: Theoretical and applied linguistics at Kobe Shoin 2, Kobe Shoin Institute for Linguistic Sciences, 1999). These two accounts have distinct predictions on how children initially interpret wh-words. The universal account predicts that children should initially interpret wh-words as universal quantifiers, whereas the existential account anticipates that children should start out with the existential interpretation. To adjudicate between the two accounts, the present study was designed to explore pre-schoolers' semantic knowledge of wh-quantification. Specifically, it investigated the interpretation of the wh-word shenme 'what' with 4-and 5-year-old Mandarin-speaking children and a control group of adults. Using a Truth Value Judgment Task (Crain and Thornton in Investigations in universal grammar: a guide to experiments on the acquisition of syntax and semantics. MIT Press, Cambridge, 1998), Experiment 1 evaluated whether children interpret the wh-word shenme 'what' as closer in meaning to the polarity sensitive item renhe 'any' or the universal quantifier suoyou 'all' in the antecedent of ruguo 'if' conditionals. Using a Question-Answer Task, Experiments 2 & 3 respectively investigated whether children interpret shenme 'what' as closer in meaning to renhe 'any' or suoyou 'all' in two types of questions: yes-no questions with the particle ma and A-not-A questions. It was found that both children and adults interpret shenme 'what' as closer in meaning to renhe 'any' than suoyou 'all'. The findings suggest that Mandarin-speaking pre-schoolers already have adult-like semantic knowledge of wh-quantification: wh-words are existential quantifiers rather than universal quantifiers. Due to the paucity of primary linguistic input, children's early mastery of the non-interrogative wh-words appear to support the biolinguistic approach to language acquisition (Chomsky in Aspects of the theory of syntax. MIT Press, Cambridge, 1965; Pinker in Language learnability and language development. Harvard University Press, Cambridge, 1984; Crain et al. in Language acquisition from a biolinguistic perspective. Neurosci Biobehav Rev, 2016. https://doi.org/10.1016/j.neubiorev.2016.09.004 ).


Assuntos
Semântica , Humanos , Masculino , Feminino , Pré-Escolar , Adulto , Psicolinguística , Idioma , Adulto Jovem , China
17.
Nano Lett ; 24(21): 6395-6402, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38757657

RESUMO

Passive daytime radiative cooling (PDRC) is a promising practice to realize sustainable thermal management with no energy and resources consumption. However, there remains a challenge of simultaneously integrating desired solar reflectivity, environmental durability, and mechanical robustness for polymeric composites with nanophotonic structures. Herein, inspired by a classical armor shell of a pangolin, we adopt a generic design strategy that harnesses supramolecular bonds between the TiO2-decorated mica microplates and cellulose nanofibers to collectively produce strong interfacial interactions for fabricating interlayer nanostructured PDRC materials. Owing to the strong light scattering excited by hierarchical nanophotonic structures, the bioinspired film demonstrates a desired reflectivity (92%) and emissivity (91%) and an excellent temperature drop of 10 °C under direct sunlight. Notably, the film guarantees high strength (41.7 MPa), toughness (10.4 MJ m-3), and excellent environmental durability. This strategy provides possibilities in designing polymeric PDRC materials, further establishing a blueprint for other functional applications like soft robots, wearable devices, etc.

18.
Dalton Trans ; 53(21): 9052-9061, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38736382

RESUMO

Si NWs@C core/shell anodes for lithium-ion batteries were synthesized via a one-step environmental-pressure chemical vapor deposition (CVD) process utilizing nano-silicon and methane as raw materials. In this structure, the silicon nanowire core is obtained by controlling the temperature above 900 °C to catalyze the growth of nano-silicon particles coated with a natural oxide layer according to the oxide-assisted growth (OAG) mechanism, while the carbon as a protective coating shell is derived from methane cracking. In contrast to the conventional nanowire catalytic approach, this method obviates the addition of metal catalysts while ensuring a straightforward and scalable process. This Si NWs@C electrode displayed excellent electrochemical performance, exhibiting high reversible capacity (745.8 mA h g-1) and excellent cycling stability (91.3% after 100 cycles at 0.5 A g-1).

19.
ACS Nano ; 18(21): 13652-13661, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38751043

RESUMO

In contemporary autonomous driving systems relying on sensor fusion, traditional digital processors encounter challenges associated with analogue-to-digital conversion and iterative vector-matrix operations, which are encumbered by limitations in terms of response time and energy consumption. In this study, we present an analogue Kalman filter circuit based on molybdenum disulfide (MoS2) memtransistor, designed to accelerate sensor fusion for precise localization in autonomous vehicle applications. The nonvolatile memory characteristics of the memtransistor allow for the storage of a fixed Kalman gain, which eliminates the data convergence and thus accelerates the processing speeds. Additionally, the modulation of multiple conductance states by the gate terminal enables fast adaptability to diverse autonomous driving scenarios by tuning multiple Kalman filter gains. Our proposed analogue Kalman filter circuit accurately estimates the position coordinates of target vehicles by fusing sensor data from light detection and ranging (LiDAR), millimeter-wave radar (Radar), and camera, and it successfully solves real-word problems in a signal-free crossroad intersection. Notably, our system achieves a 1000-fold improvement in energy efficiency compared to that of digital circuits. This work underscores the viability of a memtransistor for achieving fast, energy-efficient real-time sensing, and continuous signal processing in advanced sensor fusion technology.

20.
Cell Death Discov ; 10(1): 263, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811564

RESUMO

Diabetic foot ulcer (DFU) is a prevalent complication of diabetes that poses significant challenges in terms of treatment and management. It is characterized by heightened endothelial apoptosis and impaired angiogenesis. In this study, we aimed to investigate the role of protein kinase Cδ (PKCδ) in regulating endothelial apoptosis in diabetic wounds by promoting cholesterol biosynthesis. The expression of PKCδ was increased in human umbilical vascular endothelial cells (HUVECs) cultivated in high glucose medium and skin tissue isolated from diabetic mice. High glucose-induced HUVECs apoptosis was reduced by PKCδ inhibition with siRNA or rottlerin. RNA-seq identified two enzymes, 3-hydroxy-3-methylglutaryl-CoA synthase 1 (HMGCS1) and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), as the downstream of PKCδ. PKCδ knockdown or inhibition suppressed the expression of HMGCS1 and HMGCR and lowered free cholesterol (FC) levels. Cholesterol restored high glucose-induced apoptosis in siRNA- or rottlerin-treated HUVECs. In vivo use of rosuvastatin calcium, an inhibitor of HMGCR, downregulated free cholesterol levels and accelerated the wound healing process. In conclusion, PKCδ expression in endothelial cells was activated by high glucose, which subsequently upregulates the expression of two enzymes catalyzing cholesterol biosynthesis, HMGCS1 and HMGCR. Enhanced cholesterol biosynthesis raises free cholesterol levels, promotes endothelial apoptosis, and finally delays wound healing.

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