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1.
BMC Ophthalmol ; 24(1): 191, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664659

RESUMO

BACKGROUND: To assess the age and timeline distribution of ocular axial length shortening among myopic children treated with photobiomodulation therapy in the real world situations. METHODS: Retrospective study of photobiomodulation therapy in Chinese children aged 4 to 13 years old where axial length measurements were recorded and assessed to determine effectiveness at two age groups (4 ∼ 8 years old group and 9 ∼ 13 years old group). Data was collected from myopic children who received photobiomodulation therapy for 6 ∼ 12 months. Effectiveness of myopia control was defined as any follow-up axial length ≤ baseline axial length, confirming a reduction in axial length. Independent t-test was used to compare the effectiveness of the younger group and the older group with SPSS 22.0. RESULTS: 342 myopic children were included with mean age 8.64 ± 2.20 years and baseline mean axial length of 24.41 ± 1.17 mm. There were 85.40%, 46.30%, 71.20% and 58.30% children with axial length shortening recorded at follow-up for 1 month, 3 months, 6 months and 12 months, respectively. With respect to the axial length shortened eyes, the mean axial length difference (standard deviation) was - 0.039 (0.11) mm, -0.032 (0.11) mm, -0.037 (0.12) mm, -0.028 (0.57) mm at 1, 3, 6, and 12-month follow-up, respectively. Greater AL shortening was observed among the older group who had longer baseline axial lengths than the younger group (P < 0.001). CONCLUSIONS: Overall myopia control effectiveness using photobiomodulation therapy was shown to be age and time related, with the maximum absolute reduction in axial elongation being cumulative.


Assuntos
Comprimento Axial do Olho , Terapia com Luz de Baixa Intensidade , Miopia , Humanos , Estudos Retrospectivos , Criança , Feminino , Masculino , Miopia/fisiopatologia , Miopia/radioterapia , Adolescente , Pré-Escolar , Terapia com Luz de Baixa Intensidade/métodos , Refração Ocular/fisiologia , Seguimentos
2.
Entropy (Basel) ; 25(3)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36981408

RESUMO

Recurrent Neural Networks (RNNs) are applied in safety-critical fields such as autonomous driving, aircraft collision detection, and smart credit. They are highly susceptible to input perturbations, but little research on RNN-oriented testing techniques has been conducted, leaving a threat to a large number of sequential application domains. To address these gaps, improve the test adequacy of RNNs, find more defects, and improve the performance of RNNs models and their robustness to input perturbations. We aim to propose a test coverage metric for the underlying structure of RNNs, which is used to guide the generation of test inputs to test RNNs. Although coverage metrics have been proposed for RNNs, such as the hidden state coverage in RNN-Test, they ignore the fact that the underlying structure of RNNs is still a fully connected neural network but with an additional "delayer" that records the network state at the time of data input. We use the contributions, i.e., the combination of the outputs of neurons and the weights they emit, as the minimum computational unit of RNNs to explore the finer-grained logical structure inside the recurrent cells. Compared to existing coverage metrics, our research covers the decision mechanism of RNNs in more detail and is more likely to generate more adversarial samples and discover more flaws in the model. In this paper, we redefine the contribution coverage metric applicable to Stacked LSTMs and Stacked GRUs by considering the joint effect of neurons and weights in the underlying structure of the neural network. We propose a new coverage metric, RNNCon, which can be used to guide the generation of adversarial test inputs. And we design and implement a test framework prototype RNNCon-Test. 2 datasets, 4 LSTM models, and 4 GRU models are used to verify the effectiveness of RNNCon-Test. Compared to the current state-of-the-art study RNN-Test, RNNCon can cover a deeper decision logic of RNNs. RNNCon-Test is not only effective in identifying defects in Deep Learning (DL) systems but also in improving the performance of the model if the adversarial inputs generated by RNNCon-Test are filtered and added to the training set to retrain the model. In the case where the accuracy of the model is already high, RNNCon-Test is still able to improve the accuracy of the model by up to 0.45%.

3.
Angew Chem Int Ed Engl ; 61(21): e202116865, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35132759

RESUMO

Chemical modification of electrode materials by heteroatom dopants is crucial for improving storage performance in rechargeable batteries. Electron configurations of different dopants significantly influence the chemical interactions inbetween and the chemical bonding with the host material, yet the underlying mechanism remains unclear. We revealed competitive doping chemistry of Group IIIA elements (boron and aluminum) taking nickel-rich cathode materials as a model. A notable difference between the atomic radii of B and Al accounts for different spatial configurations of the hybridized orbital in bonding with lattice oxygen. Density functional theory calculations reveal, Al is preferentially bonded to oxygen and vice versa, and shows a much lower diffusion barrier than BIII . In the case of Al-preoccupation, the bulk diffusion of BIII is hindered. In this way, a B-rich surface and Al-rich bulk is formed, which helps to synergistically stabilize the structural evolution and surface chemistry of the cathode.

4.
J Cell Physiol ; 234(2): 1369-1379, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30076725

RESUMO

BACKGROUND: Cigarette smoking is the most well-established risk factor for colorectal cancer (CRC). However, the mechanisms of smoking-associated colorectal carcinogenesis are poorly understood. METHODS: The effects of prediagnosis tobacco use on clinical characteristics, overall survival (OS), and recurrence-free survival (RFS) were analyzed in 396 patients with CRC. Associations between smoking status and OS and RFS were evaluated using Cox's proportional hazards regression. Furthermore, the effects of nicotine on the CRC cell lines SW620 and HT-29 were evaluated using in vitro assays. RESULTS: "Ever smoking" was associated with elevated serum carcinoembryonic antigen, American Joint Committee on Cancer T category, metastasis, and poorer OS and RFS in patients with CRC (OS: hazard ratio [HR] = 1.74, 95% confidence interval [CI], 1.07-2.81, p = 0.025; RFS: HR = 1.66, 95% CI: 1.18-2.34, p = 0.004). MicroRNA (miR)-200c was downregulated in CRC and tumor-adjacent tissues from ever smokers compared with the corresponding tissues from never smokers with CRC. Nicotine inhibited miR-200c expression in a dose- and time-dependent manner in SW620 and HT-29 CRC cell lines. Nicotine induced cell proliferation, migration, and invasion and promoted the epithelial-mesenchymal transition in SW620 and HT-29 cells, and these effects were attenuated by overexpression of miR-200c. CONCLUSION: Our findings support the adverse effects of prediagnosis cigarette smoking on prognosis and clinical behavior in CRC. We demonstrate a novel oncogenic mechanism by which nicotine promotes growth and metastasis in CRC by downregulating miR-200c.


Assuntos
Movimento Celular/efeitos dos fármacos , Fumar Cigarros/efeitos adversos , Neoplasias Colorretais/etiologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , MicroRNAs/metabolismo , Nicotina/toxicidade , Células CACO-2 , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Regulação para Baixo , Feminino , Regulação Neoplásica da Expressão Gênica , Células HT29 , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Transdução de Sinais , Fatores de Tempo
5.
J Biochem Mol Toxicol ; 33(10): e22390, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31478280

RESUMO

Recent studies have established the importance of estrogen-related receptor γ (ERRγ) as a required participant for insulin secretion in pancreatic ß cells. Key downstream genes of ERRγ remain unclear in the pancreatic ß cell. To understand the molecular role of ERRγ and elucidate potential key candidate genes involved in pancreatic ß cells, the eukaryotic expression plasmid containing mouse ERRγ was constructed and transfected into NIT-1 pancreatic ß cells. Overexpression of ERRγ was confirmed by quantitative real-time reverse-transcription polymerase chain reaction and Western blot analyses. RNA-seq was conducted to get the gene expression profiling between the overexpression group cells and control cells. Differentially expressed genes (DEGs) were identified by edgR and subsequently analyzed by gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. We found that overexpression of ERRγ in pancreatic ß cells enables regulation of the expression of certain genes involved in cell apoptosis and mitochondrial function, such as TFPT, Bcl7c, Dap, Thoc6, Ube2d3, ATP5H, MPV17, and NDUFA6. GO analysis revealed that the DEGs were mainly enriched in apoptotic process, cytoplasm, and protein binding. KEGG pathway analysis demonstrated that downregulated DEGs were mainly enriched in protein processing in endoplasmic reticulum, estrogen signaling pathway, and metabolic pathways. This study helps to further understand and reposition the molecular mechanisms of ERRγ in ß cells.


Assuntos
Células Secretoras de Insulina/metabolismo , Receptores de Estrogênio/metabolismo , Animais , Perfilação da Expressão Gênica , Ontologia Genética , Humanos , Camundongos , Receptores de Estrogênio/genética , Análise de Sequência de RNA
6.
Zhongguo Zhong Yao Za Zhi ; 44(1): 53-58, 2019 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-30868812

RESUMO

Through resources investigation and sample collection,a total number of 392 Dendrobium officinale from 38 different populations,9 provinces were processed for measuring and observing.Fourteen agronomy characterizations like stem height,stem diameter,number of node in stem were selected for further classification.The cluster analysis was performed using Ward and Euclidean method.The results showed that the threshold of genetic distance was 2.77.Thirtyeight populations were divided into 6 groups.The factor analysis showed that,the leaf shape,stem shape,pitch length and leaf color were very important factors for classification.This study establish the foundation for analyzing the genetic relationship of D.officinale from different populations.


Assuntos
Dendrobium/anatomia & histologia , Dendrobium/classificação , Análise por Conglomerados , Folhas de Planta , Plantas Medicinais/anatomia & histologia , Plantas Medicinais/classificação
7.
J Asian Nat Prod Res ; 20(6): 570-580, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29376419

RESUMO

To investigate the anti-oxidant activities and mechanism of rosmarinic acid (RA) on rat bone marrow mesenchymal stem cells (rBMSCs) from ischemia-induced apoptosis in vitro, which was established using H2O2-damage and analyzed for cell viability, cell apoptosis, ROS, morphological changes, and levels of apoptosis proteins. Pretreatment with RA significantly suppressed the generation of ROS, protected the morphological changes of cells, decrease the ratio of cell apoptosis, down-regulated the level of caspase-3, caspase-9, Bax/Bcl-2, and up-regulated the level of p-PI3K. These findings suggest that RA may protect rBMSCs from H2O2-induced apoptosis by partly regulating PI3K/Akt signaling pathway and can be developed as a potential anti-apoptotic agent for therapy in cardiovascular diseases.


Assuntos
Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Células da Medula Óssea/efeitos dos fármacos , Cinamatos/farmacologia , Depsídeos/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Células Cultivadas , Peróxido de Hidrogênio , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Ácido Rosmarínico
8.
Curr Diab Rep ; 17(11): 102, 2017 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-28940103

RESUMO

PURPOSE OF REVIEW: Metabolomics is the study of dysregulated metabolites in biological materials. We reviewed the use of the technique to elucidate the genetic and environmental factors that contribute to the development of diabetic retinopathy. RECENT FINDINGS: With regard to metabolomic studies of diabetic retinopathy, the field remains in its infancy with few studies published to date and little replication of results. Vitreous and serum samples are the main tissues examined, and dysregulation in pathways such as the pentose phosphate pathway, arginine to proline pathway, polyol pathway, and ascorbic acidic pathways have been reported. Few studies have examined the metabolomic underpinnings of diabetic retinopathy. Further research is required to replicate findings to date and determine longitudinal associations with disease.


Assuntos
Retinopatia Diabética/metabolismo , Metabolômica , Biomarcadores/sangue , Diabetes Mellitus/metabolismo , Retinopatia Diabética/sangue , Humanos , Corpo Vítreo/metabolismo
9.
Pharmazie ; 71(7): 390-393, 2016 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-29441914

RESUMO

Taurochenodeoxycholic acid (TCDCA), a natural bioactive substance in animal bile, has anti-inflammatory and immunoregulatory effects. This study evaluates the effects of TCDCA on calcium/calmodulin (Ca2+/CaM) signalling mediated by G Protein Coupled Bile Acid Receptor 1 (TGR5) to provide preliminary information on the mechanism of TCDCA in immune regulation and also to benefit future research. After treatment of NR8383 and high TGR5 expression cell (TGR5-NR8383) with TCDCA (10-6 mol/L, 10-5 mol/L, and 10-4 mol/L) for 1 h, we measured TGR5 and CaM gene and protein levels by quantitative reverse transcription-polymerase chain reaction (qPCR) and western blotting, respectively. The inositol triphosphate (IP3) concentration was measured by Enzyme-linked Immunosorbent Assay (ELISA), and the Ca2+ concentration was measured by calcium fluorescent probe (Fluo-3 AM). The present study showed that the expression levels of IP3, Ca2+, and CaM in NR8383 cells were increased by TCDCA at concentrations ranging from 10-6 mol/L to 10-4 mol/L. TCDCA (10-4 mol/L) increased both the gene and protein expression of IP3and CaM through TGR5. TCDCA (10-4 mol/L or 10-5 mol/L) also increased the Ca2+ concentration via the TGR5 receptor. Our data suggest TCDCA activates Ca2+/CaM signalling via the TGR5 signalling pathway.


Assuntos
Sinalização do Cálcio/efeitos dos fármacos , Calmodulina/efeitos dos fármacos , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ácido Tauroquenodesoxicólico/farmacologia , Animais , Sinalização do Cálcio/genética , Calmodulina/biossíntese , Calmodulina/genética , Linhagem Celular , Expressão Gênica/efeitos dos fármacos , Humanos , Inositol 1,4,5-Trifosfato/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Receptores Acoplados a Proteínas G/genética
10.
Phys Chem Chem Phys ; 16(12): 5480-4, 2014 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-24514077

RESUMO

By using epoxy silane as a modifier and stabilizer, ZnO quantum dots (QDs) were synthesized by a one-step precipitation approach. The ZnO QDs acquired showed satisfactory redispersibility and exhibited strong and stable photoluminescence in both solution and dry states. When the ZnO QDs content was as high as 8 wt%, the ZnO QDs-epoxy nanocomposite was still highly transparent and luminescent. Accordingly, the ZnO QDs can be used as a luminescent material, and a cool white light emitting diode (WLED) lamp was made by encapsulating a UV chip with the nanocomposite, without traditional tricolor rare earth phosphors. Additionally, the high loading nanocomposite possessed high ultraviolet resistance, which would help to improve the lifetime of the WLED.

11.
ScientificWorldJournal ; 2014: 473504, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24892054

RESUMO

The situation sequence contains a series of complicated and multivariate random trends, which are very sudden, uncertain, and difficult to recognize and describe its principle by traditional algorithms. To solve the above questions, estimating parameters of super long situation sequence is essential, but very difficult, so this paper proposes a situation prediction method based on historical feature pattern extraction (HFPE). First, HFPE algorithm seeks similar indications from the history situation sequence recorded and weighs the link intensity between occurred indication and subsequent effect. Then it calculates the probability that a certain effect reappears according to the current indication and makes a prediction after weighting. Meanwhile, HFPE method gives an evolution algorithm to derive the prediction deviation from the views of pattern and accuracy. This algorithm can continuously promote the adaptability of HFPE through gradual fine-tuning. The method preserves the rules in sequence at its best, does not need data preprocessing, and can track and adapt to the variation of situation sequence continuously.


Assuntos
Algoritmos , Segurança Computacional , Probabilidade
12.
Pak J Pharm Sci ; 27(5 Spec no): 1523-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25176247

RESUMO

Streptococcus mutans is the primary pathogen responsible for initiating dental caries and decay. The presence of sucrose, stimulates S. mutans to produce insoluble glucans to form oral biofilm also known as dental plaque to initiate caries lesion. The GtfB and LuxS genes of S. mutans are responsible for formation and maturation of biofilm. Lactobacillus species as probiotic can reduces the count of S. mutans. In this study effect of different Lactobacillus species against the formation of S. mutans biofilm was observed. Growing biofilm in the presence of sucrose was detected using 96 well microtiter plate crystal violet assay and biofilm formation by S. mutans in the presence of Lactobacillus was detected. Gene expression of biofilm forming genes (GtfB and LuxS) was quantified through Real-time PCR. All strains of Lactobacillus potently reduced the formation of S. mutans biofilm whereas Lactobacillus acidophilus reduced the genetic expression by 60-80%. Therefore, probiotic Lactobacillus species can be used as an alternative instead of antibiotics to decrease the chance of dental caries by reducing the count of S. mutans and their gene expression to maintain good oral health.


Assuntos
Biofilmes/crescimento & desenvolvimento , Cárie Dentária/prevenção & controle , Lactobacillus/fisiologia , Probióticos , Streptococcus mutans/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Liases de Carbono-Enxofre/genética , Liases de Carbono-Enxofre/metabolismo , Cárie Dentária/microbiologia , Regulação Bacteriana da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Humanos , Lactobacillus/classificação , Streptococcus mutans/genética , Streptococcus mutans/metabolismo , Sacarose/metabolismo
13.
Geriatr Gerontol Int ; 24(4): 421-429, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38438300

RESUMO

AIM: While insulin sensitivity plays an important role in maintaining glucose metabolic homeostasis and cognitive function, its impact on postoperative delirium (POD) remains unclear. This study aimed to investigate the association between POD and indicators of insulin sensitivity, including insulin resistance and osteocalcin. METHODS: A total of 120 elderly patients undergoing joint replacement were recruited and divided into delirium and non-delirium groups. Plasma and cerebrospinal fluid (CSF) samples were collected for the analysis of biomarkers, including insulin, uncarboxylated osteocalcin (ucOC), total osteocalcin (tOC), and glucose. Insulin resistance was assessed through the homeostatic model assessment of insulin resistance (HOMA-IR). MAIN RESULTS: Out of the total, 28 patients (23.3%) experienced POD within 5 days after surgery. Patients with delirium exhibited higher levels of preoperative HOMA-IR and ucOC in CSF and plasma, and of tOC in CSF (P = 0.028, P < 0.001, P = 0.005, P = 0.019). After adjusting for variables, including age, Mini-Mental State Examination score, surgical site and preoperative fracture, only preoperative ucOC in CSF and HOMA-IR were significantly linked to the incidence of delirium (OR = 5.940, P = 0.008; OR = 1.208, P = 0.046, respectively), both of which also correlated with the severity of delirium (P = 0.007, P < 0.001). Receiver operating curve analysis indicated that preoperative HOMA-IR and ucOC in CSF might partly predict POD (area under the curve [AUC] = 0.697, 95% confidence interval [CI] = 0.501-0.775, AUC = 0.745, 95% CI = 0.659-0.860). CONCLUSIONS: We observed that preoperative elevated HOMA-IR and ucOC in CSF were associated with the incidence and severity of POD. While these preliminary results need confirmation, they suggest a potential involvement of insulin resistance and osteocalcin in the pathological mechanism of POD. Geriatr Gerontol Int 2024; 24: 421-429.


Assuntos
Artroplastia de Substituição , Delírio do Despertar , Resistência à Insulina , Humanos , Idoso , Osteocalcina , Incidência , Glucose , Artroplastia de Substituição/efeitos adversos
14.
Heliyon ; 10(2): e24421, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38293399

RESUMO

Extensive research has confirmed numerous advantages of exercise for promoting brain health. More recent studies have proposed the potential benefits of lactate, the by-product of exercise, in various aspects of brain function and disorders. However, there remains a gap in understanding the effects of lactate dosage and its impact on aged rodents. The present study first examined the long-term effects of three different doses of lactate intervention (2000 mg/kg, 1000 mg/kg, and 500 mg/kg) and high-intensity interval training (HIIT) on aging mice (20-22 months) as the 1st experiment. Subsequently, in the 2nd experiment, we investigated the long-term effects of 500 mg/kg lactate intervention and HIIT on brain neuroplasticity in aged mice (25-27 months). The results of the 1st experiment demonstrated that both HIIT and different doses of lactate intervention (500 mg/kg and 2000 mg/kg) positively impacted the neuroplasticity biomarker VEGF in the hippocampus of aging mice. Subsequently, the 2nd experiment revealed that long-term HIIT significantly improved the performance of mice in open-field, novel object recognition, and passive avoidance tests. However, lactate intervention did not significantly affect these behavioral tests. Moreover, compared to the control group, both HIIT and lactate intervention positively influenced the angiogenesis signaling pathway (p/t-AKT/ENOS/VEGF), mitochondrial biomarker (SDHA), and metabolic protein (p/t-CREB, p/t-HSL, and LDH) in the hippocampus of aged mice. Notably, only lactate intervention significantly elevated the BDNF (PGC-1α, SIRT1, and BDNF) signaling pathway and metabolic content (lactate and pyruvate). In the end, long-term HIIT and lactate intervention failed to change the protein expression of p/t-MTOR, iNOS, nNOS, HIF-1α, SYNAPSIN, SIRT3, NAMPT, CS, FNDC5 and Pan Lactic aid-Lysine in the hippocampus of aged mice. In summary, the present study proved that long-term HIIT and lactate treatment have positive effects on the brain functions of aged mice, suggesting the potential usage of lactate as a therapeutic strategy in neurodegenerative diseases in the elderly population.

15.
Artigo em Inglês | MEDLINE | ID: mdl-38952105

RESUMO

The piezoelectric properties of two-dimensional semiconductor nanobubbles present remarkable potential for application in flexible optoelectronic devices, and the piezoelectric field has emerged as an efficacious pathway for both the separation and migration of photogenerated electron-hole pairs, along with inhibition of recombination. However, the comprehension and control of photogenerated carrier dynamics within nanobubbles still remain inadequate. Hence, this study is dedicated to underscore the importance of in situ detection and detailed characterization of photogenerated electron-hole pairs in nanobubbles to enrich understanding and strategic manipulation in two-dimensional semiconductor materials. Utilizing frequency modulation kelvin probe force microscopy (FM-KPFM) and strain gradient distribution techniques, the existence of a piezoelectric field in monolayer WS2 nanobubbles was confirmed. Combining w/o and with illumination FM-KPFM, second-order capacitance gradient technique and in situ nanoscale tip-enhanced photoluminescence characterization techniques, the interrelationships among the piezoelectric effect, interlayer carrier transfer, and the funneling effect for photocarrier dynamics process across various nanobubble sizes were revealed. Notably, for a WS2/graphene bubble height of 15.45 nm, a 0 mV surface potential difference was recorded in the bubble region w/o and with illumination, indicating a mutual offset of piezoelectric effect, interlayer carrier transfer, and the funneling effect. This phenomenon is prevalent in transition metal dichalcogenides materials exhibiting inversion symmetry breaking. The implication of our study is profound for advancing the understanding of the dynamics of photogenerated electron-hole pair in nonuniform strain piezoelectric systems, and offers a reliable framework for the separation and modulation of photogenerated electron-hole pair in flexible optoelectronic devices and photocatalytic applications.

16.
ACS Appl Mater Interfaces ; 16(15): 18971-18979, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38578663

RESUMO

The formation of a solid electrolyte interphase on carbon anodes causes irreversible loss of Na+ ions, significantly compromising the energy density of Na-ion full cells. Sodium compensation additives can effectively address the irreversible sodium loss but suffer from high decomposition voltage induced by low electrochemical activity. Herein, we propose a universal electrocatalytic sodium compensation strategy by introducing a carbon nanotube (CNT)/MnO2 catalyst to realize full utilization of sodium compensation additives at a much-reduced decomposition voltage. The well-organized CNT/MnO2 composite with high catalytic activity, good electronic conductivity, and abundant reaction sites enables sodium compensation additives to decompose at significantly reduced voltages (from 4.40 to 3.90 V vs Na+/Na for sodium oxalate, 3.88 V for sodium carbonate, and even 3.80 V for sodium citrate). As a result, sodium oxalate as the optimal additive achieves a specific capacity of 394 mAh g-1, almost reaching its theoretical capacity in the first charge, increasing the energy density of the Na-ion full cell from 111 to 158 Wh kg-1 with improved cycle stability and rate capability. This work offers a valuable approach to enhance sodium compensation efficiency, promising high-performance energy storage devices in the future.

17.
Hepatogastroenterology ; 59(117): 1541-3, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22172375

RESUMO

BACKGROUND/AIMS: To evaluate the prognostic value of surgical operation-related factors in patients with primary liver cancer (PLC). METHODOLOGY: A retrospective study was carried out analyzing the data of 114 patients with PLC undergoing hepatic resection from January 2002 to December 2009. Survival rates were analyzed using Kaplan-Meier curve and log-rank tests were employed to compare the survival rates observed in those patients with surgical operation-related factors (e.g. operation method, time, portal blockage, complications, resection margin, amount of intraoperative blood loss and amount of blood transfusion), and bivariate correlation analysis was used to examine the associations of these surgical operation-related factors. RESULTS: Intraoperative blood loss, amount of blood transfusion and operation time were significant predictors for patients with PLC after hepatic resection (p<0.05). The operation method, resection margin, portal blockage and complications (e.g. intra-abdominal infections, intra-abdominal hemorrhage, gastro-intestinal hemorrhage, biliary leakage, etc.) were not significant prognostic factors (p>0.05). There was a positive correlation between intraoperative blood loss, amount of blood transfusion, portal blockage time and operation time, in addition, a negative correlation was found between resection margin and the operation method. CONCLUSIONS: Hepatic surgery can improve the patients prognosis if the operation time is shortened, and the amount of intraoperative blood transfusion and blood loss lessened.


Assuntos
Perda Sanguínea Cirúrgica , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Transfusão de Sangue , Volume Sanguíneo , Feminino , Hepatectomia , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
18.
Chem Asian J ; 17(12): e202200213, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35560519

RESUMO

With the ever increasing demand for low-cost and economic sustainable energy storage, Na-ion batteries have received much attention for the application on large-scale energy storage for electric grids because of the worldwide distribution and natural abundance of sodium element, low solvation energy of Na+ ion in the electrolyte and the low cost of Al as current collectors. Starting from a brief comparison with Li-ion batteries, this review summarizes the current understanding of layered oxide cathode/electrolyte interphase in NIBs, and discusses the related degradation mechanisms, such as surface reconstruction and transition metal dissolution. Recent advances in constructing stable cathode electrolyte interface (CEI) on layered oxide cathode are systematically summarized, including surface modification of layered oxide cathode materials and formulation of electrolyte. Urgent challenges are detailed in order to provide insight into the imminent developments of NIBs.

19.
Phys Rev E ; 105(2): L022901, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35291130

RESUMO

In this letter, we present evidence for a mechanism responsible for the nonclassical nonlinear dynamics observed in many cemented granular materials that are generally classified as mesoscopic nonlinear elastic materials. We demonstrate numerically that force chains are created within the complex grain-pore network of these materials when subjected to dynamic loading. The interface properties between grains along with the sharp and localized increase of the stress occurring at the grain-grain contacts leads to a reversible decrease of the elastic properties at macroscopic scale and peculiar effects on the propagation of elastic waves when grain boundary properties are appropriately considered. These effects are observed for relatively small amplitudes of the elastic waves, i.e., within tens of microstrain, and relatively large wavelengths, i.e., orders of magnitude larger than the material constituents. The mechanics are investigated numerically using the hybrid finite-discrete-element method and match those observed experimentally using nonlinear resonant ultrasound spectroscopy.

20.
Theranostics ; 12(17): 7450-7464, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438486

RESUMO

Rationale: Hepatocellular carcinoma (HCC) is one of the most severe cancers worldwide, with few effective targeted therapies for HCC. Lipid metabolic reprogramming is emerged as a hallmark of cancer metabolism that guides response to antitumoral therapies. Such lipid metabolic alteration in cancers is critically regulated by the mammalian target of rapamycin mTOR, which is considered as a promising therapeutic target. Despite efforts, mTOR inhibitors (mTORi) have produced limited response clinically, partly due to incomplete knowledge of mTORC1 addiction in cancers. Methods: CRISPR-Cas9 system was used to establish Hpcal1 null mice. The liver cancer model in mice was generated using Hpcal1-deficient mice with diethylnitrosamine (DEN) /CCL4 or MYC/Trp53-/- via hydrodynamic tail-vein injection. RNA-sequencing (RNA-seq) was used to identify potential signaling pathways. The expression of HPCAL1 and mTOR signaling were determined using quantitative polymerase chain reaction (qPCR), western blot and immunohistochemistry. The role of Hpcal1 in liver tumorigenesis and its response to mTORi was assessed by CCK-8 measurements, colony formation assay and in mouse model. Results: In this study, we identified hippocalcin-like protein 1 (HPCAL1) as an important negative regulator of de novo lipid biosynthesis and mTOR signaling activation, limiting liver tumorigenesis and establishing a metabolic vulnerability of HCC in mice. Genetic loss of HPCAL1 rendered HCC mTORC1-addicted and sensitive to mTORi AZD-8055 in vitro and in vivo. Importantly, HPCAL1 expression was inversely correlated with the levels of mTOR phosphorylation and several critical lipid biosynthesis enzymes in human specimens. Mechanistically, HPCAL1 directly bound to RuvB Like AAA ATPase 1 (RUVBL1), inhibiting the assembly of TEL2-TTI1-TTI2 (TTT)-RUVBL complex and subsequent leading the mTOR signaling suppression. Conclusion: We uncover a metabolic vulnerability and mTOR addiction in HCC with HPCAL1 loss that provides a selective therapeutic window for HCC with mTORC1 hyperactivation using mTORi.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Carcinogênese , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Proteínas de Transporte/metabolismo , Transformação Celular Neoplásica , DNA Helicases/metabolismo , Hipocalcina/metabolismo , Metabolismo dos Lipídeos , Lipídeos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Mamíferos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
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