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1.
Proc Natl Acad Sci U S A ; 121(6): e2316775121, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38300874

RESUMEN

High pressure has triggered various novel states/properties in condensed matter, as the most representative and dramatic example being near-room-temperature superconductivity in highly pressured hydrides (~200 GPa). However, the mechanism of superconductivity is not confirmed, due to the lacking of effective approach to probe the electronic band structure under such high pressures. Here, we theoretically propose that the band structure and electron-phonon coupling (EPC) of high-pressure quantum states can be probed by solid-state high harmonic generation (sHHG). This strategy is investigated in high-pressure Im-3m H3S by the state-of-the-art first-principles time-dependent density-functional theory simulations, where the sHHG is revealed to be strongly dependent on the electronic structures and EPC. The dispersion of multiple bands near the Fermi level is effectively retrieved along different momentum directions. Our study provides unique insights into the potential all-optical route for band structure and EPC probing of high-pressure quantum states, which is expected to be helpful for the experimental exploration of high-pressure superconductivity in the future.

2.
Ecol Appl ; 34(4): e2969, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38562107

RESUMEN

Drought and nitrogen enrichment could profoundly affect the productivity of semiarid ecosystems. However, how ecosystem productivity will respond to different drought scenarios, especially with a concurrent increase in nitrogen availability, is still poorly understood. Using data from a 4-year field experiment conducted in a semiarid temperate steppe, we explored the responses of aboveground net primary productivity (ANPP) to different drought scenarios and nitrogen addition, and the underlying mechanisms linking soil properties, plant species richness, functional diversity (community-weighted means of plant traits, functional dispersion) and phylogenetic diversity (net relatedness index) to ANPP. Our results showed that completely excluding precipitation in June (1-month intense drought) and reducing half the precipitation amount from June to August (season-long chronic drought) both significantly reduced ANPP, with the latter having a more negative impact on ANPP. However, reducing half of the precipitation frequency from June to August (precipitation redistribution) had no significant effect on ANPP. Nitrogen addition increased ANPP irrespective of drought scenarios. ANPP was primarily determined by soil moisture and nitrogen availability by regulating the community-weighted means of plant height, rather than other aspects of plant diversity. Our findings suggest that precipitation amount is more important than precipitation redistribution in influencing the productivity of temperate steppe, and nitrogen supply could alleviate the adverse impacts of drought on grassland productivity. Our study advances the mechanistic understanding of how the temperate grassland responds to drought stress, and implies that management strategies to protect tall species in the community would be beneficial for maintaining the productivity and carbon sequestration of grassland ecosystems under climate drought.


Asunto(s)
Sequías , Pradera , Nitrógeno , Nitrógeno/metabolismo , Plantas/clasificación , Suelo/química , China
3.
Mol Genet Genomics ; 297(2): 485-494, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35146538

RESUMEN

Eucommia ulmoides (E. ulmoides) is a deciduous perennial tree belonging to the order Garryales, and is known as "living fossil" plant, along with ginkgo (Ginkgo biloba), metaspaca (Metasequoia glyptostroboides) and dove tree (Davidia involucrata Baill). However, the genetic diversity and population structure of E. ulmoides are still  ambiguous nowdays. In this study, we re-sequenced the genomes of 12 E. ulmoides accessions from different major climatic geography regions in China to elucidate the genetic diversity, population structure and evolutionary pattern. By integration of phylogenetic analysis, principal component analysis and population structure analysis based on a number of high-quality SNPs, a total of 12 E. ulmoides accessions were clustered into four different groups. This result is consistent with their geographical location except for group samples from Shanghai and Hunan province. E. ulmoides accessions from Hunan province exhibited a closer genetic relationship with E. ulmoides accessions from Shanghai in China compared with other regions, which is also supported by the result of population structure analyses. Genetic diversity analysis further revealed that E. ulmoides samples in Shanghai and Hunan province were with higher genetic diversity than those in other regions in this study. In addition, we treated the E. ulmoides materials from Shanghai and Hunan province as group A, and the other materials from other places as group B, and then analyzed the evolutionary pattern of E. ulmoides. The result showed the significant differentiation (Fst = 0.1545) between group A and group B. Some candidate highly divergent genome regions were identified in group A by selective sweep analyses, and the function analysis of candidate genes in these regions showed that biological regulation processes could be correlated with the Eu-rubber biosynthesis. Notably, nine genes were identified from selective sweep regions. They were involved in the Eu-rubber biosynthesis and expressed in rubber containing tissues. The genetic diversity research and evolution model of E. ulmoides were preliminarily explored in this study, which laid the foundation for the protection of germplasm resources and the development and utilization of multipurpose germplasm resources in the future.


Asunto(s)
Eucommiaceae , China , Eucommiaceae/genética , Variación Genética/genética , Filogenia
4.
Med Sci Monit ; 22: 1654-62, 2016 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-27184872

RESUMEN

BACKGROUND Circulating tumor cells (CTCs) are tumor cells that leave the primary tumor site and enter the bloodstream, where they can spread to other organs; they are very important in the diagnosis, treatment, and prognosis of malignant tumors. However, few studies have investigated CTCs in esophageal squamous cell carcinoma (ESCC). The aim of this study was to investigate the CTCs in blood of ESCC patients and its potential relevance to clinicopathological features and prognosis. MATERIAL AND METHODS CTCs were acquired by a negative enrichment method that used magnetic activated cell sorting (MACSTM). Fluorescent immunohistochemistry (IHC) was used to identify the CTCs. Then, the positive CTC patients with ESCC were analyzed, after which the relationship between CTCs and clinicopathologic features was evaluated. RESULTS In the present study, 62 out of 140 (44.3%) patients with ESCC were positive for CTCs. The positive rate of CTCs was significantly related with stage of ESCC patients (P=0.013). However, there was no relationship between CTC status and age, sex, smoking tumor history, tumor location, differentiation of tumor, lymphatic invasion, or lymph venous invasion (P>0.05). Kaplan-Meier analysis showed that patients positive for CTCs had significantly shorter survival time than patients negative for CTCs. Multivariate analysis demonstrated that stage and CTC status were significant prognostic factors for patients with ESCC. CONCLUSIONS CTCs positivity is an independent prognostic biomarker that indicates a worse prognosis for patients with ESCC.


Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/patología , Técnica del Anticuerpo Fluorescente/métodos , Células Neoplásicas Circulantes/patología , Adulto , Anciano , Biomarcadores de Tumor/sangre , Carcinoma de Células Escamosas/sangre , Carcinoma de Células Escamosas/diagnóstico por imagen , Neoplasias Esofágicas/sangre , Neoplasias Esofágicas/diagnóstico por imagen , Carcinoma de Células Escamosas de Esófago , Femenino , Humanos , Inmunohistoquímica/métodos , Estimación de Kaplan-Meier , Metástasis Linfática , Masculino , Persona de Mediana Edad , Pronóstico
5.
Zhong Yao Cai ; 38(5): 1066-9, 2015 May.
Artículo en Zh | MEDLINE | ID: mdl-26767302

RESUMEN

OBJECTIVE: To study the correlation of characteristic spectra of Vinegar Corydalis Rhizoma decoction pieces, water decoction and formula granules by HPLC, and to investigate the transfer of the main chemical constituents between three different forms. METHODS: The analysis was carried out by a Phenomenex Gemini C18 column (250 mm x 4.6 mm,5 µm) with acetonitrile-1% acetic acid and ammonium acetate buffer solution (pH 6.0) as the mobile phase in a gradient elution mode. The detection wavelength was 280 nm with a flow rate of 0.8 mL /min. The column temperature was 30 degrees C. The characteristic spectra from 11 batches of Vinegar Corydalis Rhizoma decoction pieces, 11 batches of water decoction and 11 batches of formula granules were established respectively. RESULTS: Ten peaks in the HPLC characteristic spectra from 11 batches of formula granules could be tracked in the water decoction, nine peaks in the HPLC characteristic spectra could be tracked in the decoction pieces. In the ten common peaks, four components such as protopine, palnatine chloride, berberine hydrochloride and tetrahydropalmatine were verified. CONCLUSION: The main chemical components of Vinegar Corydalis Rhizoma decoction pieces, water decoction and formula granules are basically the same, the common component contents have similar proportion.


Asunto(s)
Corydalis/química , Medicamentos Herbarios Chinos/química , Rizoma/química , Ácido Acético , Benzofenantridinas , Berberina , Alcaloides de Berberina , Cromatografía Líquida de Alta Presión , Temperatura , Agua
6.
Zhongguo Dang Dai Er Ke Za Zhi ; 17(8): 847-51, 2015 Aug.
Artículo en Zh | MEDLINE | ID: mdl-26287351

RESUMEN

OBJECTIVE: To compare the differences of clinical efficacy between heated humidified high-flow nasal cannula (HHHFNC) ventilation and nasal continuous positive airway pressure (NCPAP) in the treatment of respiratory distress syndrome (RDS) in very low birth weight (VLBW) infants. METHODS: A total of 66 VLBW infants who were admitted to the neonatal intensive care unit were diagnosed with RDS, and they were randomly assigned to HHHFNC group and NCPAP group after receiving treatment with porcine pulmonary surfactant and conventional treatment. The changes in clinical symptoms and the incidence of complications were observed in the two groups. RESULTS: The HHHFN group had significantly earlier first milk feeding and full enteral feeding, significantly shorter oxygen exposure time and invasive ventilation time, and significantly lower incidences of second intubation within 7 days, nasal injury, air leak, and abdominal distention, as compared with the NCPAP group. CONCLUSIONS: Compared with NCPAP, HHHFNC causes slighter injury and has better tolerability, and it can be considered as the first choice of noninvasive ventilation in the treatment of RDS in VLBW infants.


Asunto(s)
Presión de las Vías Aéreas Positiva Contínua/métodos , Recién Nacido de muy Bajo Peso , Síndrome de Dificultad Respiratoria del Recién Nacido/terapia , Femenino , Humanos , Recién Nacido , Masculino
7.
ScientificWorldJournal ; 2014: 186749, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24701144

RESUMEN

We develop a novel maximum neighborhood margin discriminant projection (MNMDP) technique for dimensionality reduction of high-dimensional data. It utilizes both the local information and class information to model the intraclass and interclass neighborhood scatters. By maximizing the margin between intraclass and interclass neighborhoods of all points, MNMDP cannot only detect the true intrinsic manifold structure of the data but also strengthen the pattern discrimination among different classes. To verify the classification performance of the proposed MNMDP, it is applied to the PolyU HRF and FKP databases, the AR face database, and the UCI Musk database, in comparison with the competing methods such as PCA and LDA. The experimental results demonstrate the effectiveness of our MNMDP in pattern classification.


Asunto(s)
Interpretación Estadística de Datos , Bases de Datos Factuales/clasificación , Análisis Discriminante
8.
IEEE Trans Pattern Anal Mach Intell ; 46(5): 3463-3479, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38096091

RESUMEN

The effectiveness of active learning largely depends on the sampling efficiency of the acquisition function. Expected Loss Reduction (ELR) focuses on a Bayesian estimate of the reduction in classification error, and more general costs fit in the same framework. We propose Bayesian Estimate of Mean Proper Scores (BEMPS) to estimate the increase in strictly proper scores such as log probability or negative mean square error within this framework. We also prove convergence results for this general class of costs. To facilitate better experimentation with the new acquisition functions, we develop a complementary batch AL algorithm that encourages diversity in the vector of expected changes in scores for unlabeled data. To allow high-performance classifiers, we combine deep ensembles, and dynamic validation set construction on pretrained models, and further speed up the ensemble process with the idea of Monte Carlo Dropout. Extensive experiments on both texts and images show that the use of mean square error and log probability with BEMPS yields robust acquisition functions and well-calibrated classifiers, and consistently outperforms the others tested. The advantages of BEMPS over the others are further supported by a set of qualitative analyses, where we visualise their sampling behaviour using data maps and t-SNE plots.

9.
Neural Netw ; 170: 176-189, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37989039

RESUMEN

Knowledge distillation (KD) is a widely adopted model compression technique for improving the performance of compact student models, by utilizing the "dark knowledge" of a large teacher model. However, previous studies have not adequately investigated the effectiveness of supervision from the teacher model, and overconfident predictions in the student model may degrade its performance. In this work, we propose a novel framework, Teacher-Student Complementary Sample Contrastive Distillation (TSCSCD), that alleviate these challenges. TSCSCD consists of three key components: Contrastive Sample Hardness (CSH), Supervision Signal Correction (SSC), and Student Self-Learning (SSL). Specifically, CSH evaluates the teacher's supervision for each sample by comparing the predictions of two compact models, one distilled from the teacher and the other trained from scratch. SSC corrects weak supervision according to CSH, while SSL employs integrated learning among multi-classifiers to regularize overconfident predictions. Extensive experiments on four real-world datasets demonstrate that TSCSCD outperforms recent state-of-the-art knowledge distillation techniques.


Asunto(s)
Compresión de Datos , Humanos , Conocimiento , Aprendizaje , Estudiantes
10.
J Colloid Interface Sci ; 673: 616-627, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38897063

RESUMEN

Oxygen evolution reaction (OER) is the efficiency limiting half-reaction in water electrolysis for green hydrogen production due to the 4-electron multistep process with sluggish kinetics. The electrooxidation of thermodynamically more favorable organics accompanied by CC coupling is a promising way to synthesize value-added chemicals instead of OER. Efficient catalyst is of paramount importance to fulfill such a goal. Herein, a molybdenum iron carbide-copper hybrid (Mo2C-FeCu) was designed as anodic catalyst, which demonstrated decent OER catalytic capability with low overpotential of 238 mV at response current density of 10 mA cm-2 and fine stability. More importantly, the Mo2C-FeCu enabled electrooxidation assisted aldol condensation of phenylcarbinol with α-H containing alcohol/ketone in weak alkali electrolyte to selective synthesize cinnamaldehyde/benzalacetone at reduced potential. The hydroxyl and superoxide intermediate radicals generated at high potential are deemed to be responsible for the electrooxidation of phenylcarbinol and aldol condensation reactions to afford cinnamaldehyde/benzalacetone. The current work showcases an electrochemical-chemical combined CC coupling reaction to prepare organic chemicals, we believe more widespread organics can be synthesized by tailored electrochemical reactions.

11.
Sci Total Environ ; 927: 172276, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38583634

RESUMEN

The increases in extent and frequency of extreme drought events and increased nitrogen (N) deposition due to global change are expected to have profound impacts on carbon cycling in semi-arid grasslands. However, how ecosystem CO2 exchange processes respond to different drought scenarios individually and interactively with N addition remains uncertain. In this study, we experimentally explored the effects of different drought scenarios (early season extreme drought, 50 % reduction in precipitation amount, and 50 % reduction in precipitation events) and N addition on net ecosystem CO2 exchange (NEE), ecosystem respiration (ER), and gross ecosystem productivity (GEP) over three growing seasons (2019-2021) in a semi-arid grassland in northern China. The growing-season ecosystem carbon fluxes in response to drought and N addition were influenced by inter-annual precipitation changes, with 2019 as a normal precipitation year, and 2020 and 2021 as wet years. Early season extreme drought stimulated NEE by reducing ER. 50 % reduction in precipitation amount decreased ER and GEP consistently in three years, but only significantly suppressed NEE in 2019. 50 % reduction in precipitation events stimulated NEE. Nitrogen addition stimulated NEE, ER, and GEP, but only significantly in wet years. The structural equation models showed that changes in carbon fluxes were regulated by soil moisture, soil temperature, microbial biomass nitrogen (MBN), and the key plant functional traits. Decreased community-weighted means of specific leaf area (CWMSLA) was closely related to the reduced ER and GEP under early season extreme drought and 50 % reduction in precipitation amount. While increased community-weighted means of plant height (CWMPH) largely accounted for the stimulated ER and GEP under 50 % reduction in precipitation events. Our study stresses the distinct effects of different drought scenarios and N enrichment on carbon fluxes, and highlights the importance of soil traits and the key plant traits in determining carbon exchange in this water-limited ecosystem.


Asunto(s)
Ciclo del Carbono , Sequías , Pradera , Nitrógeno , Nitrógeno/análisis , China , Lluvia , Cambio Climático , Ecosistema , Carbono/metabolismo , Estaciones del Año
12.
J Asian Nat Prod Res ; 15(1): 46-52, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23323600

RESUMEN

Four new metabolites M-1 [1,2,18,19-tetradehydro-4-demethyl-3,17-epoxy-7,20(2H,19H)-cyclovobasan], M-2 [1,2,4,21,18,19-hexadehydro-4-demethyl-3,17-epoxy-7,20(2H,19H)-cyclovobasan], M-3 [1,2,18,19-tetradehydro-4-demethyl-4-formaldehyde-3,17-epoxy-7,20(2H,19H)-cyclovobasan], and M-4 [1,2,4,21,18,19-hexadehydro-4-demethyl-4-oxy-3,17-epoxy-7,20(2H,19H)-cyclovobasan] were isolated from the chloroform extract of koumine incubated with phenobarbital-treated rat liver microsomes. The structures of M-1, M-2, M-3, and M-4 were elucidated by spectroscopic methods including ESI-TOF-MS, 1D, and 2D NMR experiments. The metabolic pathway of koumine was proposed. The cytotoxic activities between koumine and its metabolites were also compared in the A549 cell line.


Asunto(s)
Alcaloides Indólicos/aislamiento & purificación , Microsomas Hepáticos/metabolismo , Algoritmos , Animales , Cromatografía Líquida de Alta Presión , Humanos , Alcaloides Indólicos/química , Alcaloides Indólicos/metabolismo , Alcaloides Indólicos/farmacología , Masculino , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Fenobarbital/farmacología , Ratas , Ratas Wistar
13.
Artículo en Inglés | MEDLINE | ID: mdl-37028080

RESUMEN

Continual learning (CL) is a machine learning paradigm that accumulates knowledge while learning sequentially. The main challenge in CL is catastrophic forgetting of previously seen tasks, which occurs due to shifts in the probability distribution. To retain knowledge, existing CL models often save some past examples and revisit them while learning new tasks. As a result, the size of saved samples dramatically increases as more samples are seen. To address this issue, we introduce an efficient CL method by storing only a few samples to achieve good performance. Specifically, we propose a dynamic prototype-guided memory replay (PMR) module, where synthetic prototypes serve as knowledge representations and guide the sample selection for memory replay. This module is integrated into an online meta-learning (OML) model for efficient knowledge transfer. We conduct extensive experiments on the CL benchmark text classification datasets and examine the effect of training set order on the performance of CL models. The experimental results demonstrate the superiority our approach in terms of accuracy and efficiency.

14.
Neural Netw ; 157: 364-376, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36403345

RESUMEN

Learning graph embeddings for high-dimensional data is an important technology for dimensionality reduction. The learning process is expected to preserve the discriminative and geometric information of high-dimensional data in a new low-dimensional subspace via either manual or automatic graph construction. Although both manual and automatic graph constructions can capture the geometry and discrimination of data to a certain degree, they working alone cannot fully explore the underlying data structure. To learn and preserve more discriminative and geometric information of the high-dimensional data in the low-dimensional subspace as much as possible, we develop a novel Discriminative and Geometry-Preserving Adaptive Graph Embedding (DGPAGE). It systematically integrates manual and adaptive graph constructions in one unified graph embedding framework, which is able to effectively inject the essential information of data involved in predefined graphs into the learning of an adaptive graph, in order to achieve both adaptability and specificity of data. Learning the adaptive graph jointly with the optimized projections, DGPAGE can generate an embedded subspace that has better pattern discrimination for image classification. Results derived from extensive experiments on image data sets have shown that DGPAGE outperforms the state-of-the-art graph-based dimensionality reduction methods. The ablation studies show that it is beneficial to have an integrated framework, like DGPAGE, that brings together the advantages of manual/adaptive graph construction.


Asunto(s)
Algoritmos , Reconocimiento de Normas Patrones Automatizadas , Reconocimiento de Normas Patrones Automatizadas/métodos , Aprendizaje
15.
Int J Med Inform ; 179: 105228, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37774429

RESUMEN

BACKGROUND: Early identification of pregnant women at high risk of developing gestational diabetes (GDM) is desirable as effective lifestyle interventions are available to prevent GDM and to reduce associated adverse outcomes. Personalised probability of developing GDM during pregnancy can be determined using a risk prediction model. These models extend from traditional statistics to machine learning methods; however, accuracy remains sub-optimal. OBJECTIVE: We aimed to compare multiple machine learning algorithms to develop GDM risk prediction models, then to determine the optimal model for predicting GDM. METHODS: A supervised machine learning predictive analysis was performed on data from routine antenatal care at a large health service network from January 2016 to June 2021. Predictor set 1 were sourced from the existing, internationally validated Monash GDM model: GDM history, body mass index, ethnicity, age, family history of diabetes, and past poor obstetric history. New models with different predictors were developed, considering statistical principles with inclusion of more robust continuous and derivative variables. A randomly selected 80% dataset was used for model development, with 20% for validation. Performance measures, including calibration and discrimination metrics, were assessed. Decision curve analysis was performed. RESULTS: Upon internal validation, the machine learning and logistic regression model's area under the curve (AUC) ranged from 71% to 93% across the different algorithms, with the best being the CatBoost Classifier (CBC). Based on the default cut-off point of 0.32, the performance of CBC on predictor set 4 was: Accuracy (85%), Precision (90%), Recall (78%), F1-score (84%), Sensitivity (81%), Specificity (90%), positive predictive value (92%), negative predictive value (78%), and Brier Score (0.39). CONCLUSIONS: In this study, machine learning approaches achieved the best predictive performance over traditional statistical methods, increasing from 75 to 93%. The CatBoost classifier method achieved the best with the model including continuous variables.

16.
Front Nutr ; 10: 1172982, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37275633

RESUMEN

The dual epidemic of obesity and diabetes mellitus is becoming an important worldwide public health issue. "Diabesity" is the term used to describe the combined detrimental health effects of both diabetes mellitus and obesity/overweight. Currently, food-derived bioactive compounds are suggested to alleviate diabesity. Blueberries are rich in bioactive anthocyanins, which are associated with contributing to preventing obesity and diabetes mellitus. However, the accurate active compounds and the underlying mechanism are still unclear. The objective of this study was to investigate the beneficial effects of blueberry anthocyanin on diabesity. In total, five anthocyanins (delphinidin-3-O-galactoside, delphinidin-3-O-glucoside, petunidin-3-O-galactoside, petunidin-3-O-glucoside, and malvidin-3-O-galactoside) were isolated from rabbiteye blueberry (Vaccinium virgatum) cultivar "Garden blue." All these anthocyanins exhibited oxygen radical absorbance capacity (ORAC), scavenging power of ABTS+, and DPPH-free radical and inhibitory activity of α-glucosidase in vitro. Moreover, some compounds improved glucose uptake and attenuated lipid accumulation in high glucose and oleic acid-treated HepG2 cells. All these results suggest that blueberry anthocyanins have potential antioxidant, hypoglycemic, and hypolipidemic effects, which may benefit the treatment of diabesity.

17.
Quant Imaging Med Surg ; 13(10): 6965-6978, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37869307

RESUMEN

Background: Prostate cancer rates have been steadily increasing in recent years. As high-precision radiation therapy methods, stereotactic body radiation therapy (SBRT) and carbon-ion radiation therapy (CIRT) have unique advantages. Analyzing the dosimetric differences between SBRT and CIRT in the treatment of localized prostate cancer can help provide patients with more accurate, individualized treatment plans. Methods: We selected computed tomography positioning images and the contours of target volumes of 16 patients with localized prostate cancer who received radiotherapy. We delineated the organs at risk (OARs) on the CyberKnife (CK) treatment planning system (TPS) MultiPlan4.0, which were imported into the CIRT uniform scanning TPS HIMM-1 ci-Plan. Two treatment plans, SBRT and CIRT, were designed for the same patient, and we used SPSS 22.0 for the statistical analysis of data. Results: Both SBRT and CIRT plans met the prescribed dose requirements. In terms of target volume exposure dose, D2 (P<0.001), D5 (P<0.001), D50 (P<0.001), D90 (P=0.029), D95 (P<0.001), D98 (P<0.001), and Dmean (P<0.001) under SBRT were significantly higher than those under CIRT; the conformity index (CI) under SBRT was significantly better than that under CIRT (P<0.001); the target volume coverage rate (V95%) and dose homogeneity index (HI) under CIRT were significantly better than those under SBRT (P<0.001). In terms of OAR exposure dosage, the Dmax of the bladder and rectum under SBRT was significantly lower than that under CIRT (P<0.001), but Dmean was in the other direction; the exposure dose of the intestinal tract under CIRT was significantly lower than that under SBRT (P<0.05); Dmax of the femoral head under CIRT was significantly lower than that under SBRT (P<0.05), and there was no statistical difference between them at other doses. Conclusions: In this study, we found that when CIRT was used for treating localized prostate cancer, the dose distribution in target volume was more homogeneous and the coverage rate was higher; the average dose of OARs was lower. SBRT had a better CI and higher dose in target volume; the dose hotspot was lower in OARs. It is important to comprehensively consider the dose relationship between local tumor and surrounding tissues when selecting treatment plans.

18.
Front Plant Sci ; 14: 1259858, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37818321

RESUMEN

Introduction: Dryland ecosystems face serious threats from climate change. Establishing the spatial pattern of ecosystem multifunctionality, maximum height and the correlation of biodiversity patterns with climate change is important for understanding changes in complex ecosystem processes. However, the understanding of their relationships across large spatial areas remains limited in drylands. Methods: Accordingly, this study examined the spatial patterns of ecosystem multifunctionality, maximum height and considered a set of potential environmental drivers by investigating natural shrub communities in Northwest China. Results: We found that the ecosystem multifunctionality (EMF) and maximum height of shrub communities were both affected by longitude, which was positively correlated with the precipitation gradient. Specifically, the EMF was driven by high precipitation seasonality, and the maximum height was driven by high precipitation stability during the growing season. Among the multiple biodiversity predictors, species beta diversity (SD-beta) is the most common in determining EMF, although this relationship is weak. Discussion: Unlike tree life form, we did not observe biodiversity-maximum height relationships in shrub communities. Based on these results, we suggest that more attention should be paid to the climatical fluctuations mediated biodiversity mechanisms, which are tightly correlated with ecosystem's service capacity and resistance capacity under a rapid climate change scenario in the future.

19.
Nanomedicine (Lond) ; 18(29): 2143-2157, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38127626

RESUMEN

Aim: This study focused on treating periodontitis with bacterial infection and local over accumulation of reactive oxygen species. Materials & methods: Polydopamine nanoparticles (PDA NPs) were exploited as efficient carriers for encapsulated metronidazole (MNZ). The therapeutic efficacy and biocompatibility of PDA@MNZ NPs were investigated through both in vitro and in vivo studies. Results: The nanodrug PDA@MNZ NPs were successfully fabricated, with well-defined physicochemical characteristics. In vitro, the PDA@MNZ NPs effectively eliminated intracellular reactive oxygen species and inhibited the growth of Porphyromonas gingivalis. Moreover, the PDA@MNZ NPs exhibited synergistic therapy for periodontitisin in vivo. Conclusion: PDA@MNZ NPs were confirmed with exceptional antimicrobial and antioxidant functions, offering a promising avenue for synergistic therapy in periodontitis.


Asunto(s)
Indoles , Nanopartículas , Periodontitis , Polímeros , Humanos , Metronidazol/farmacología , Antioxidantes/farmacología , Nanomedicina , Especies Reactivas de Oxígeno , Antibacterianos/farmacología , Periodontitis/tratamiento farmacológico
20.
Psychiatry Res ; 327: 115265, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37348404

RESUMEN

Cluster analyzes have been widely used in mental health research to decompose inter-individual heterogeneity by identifying more homogeneous subgroups of individuals. However, despite advances in new algorithms and increasing popularity, there is little guidance on model choice, analytical framework and reporting requirements. In this paper, we aimed to address this gap by introducing the philosophy, design, advantages/disadvantages and implementation of major algorithms that are particularly relevant in mental health research. Extensions of basic models, such as kernel methods, deep learning, semi-supervised clustering, and clustering ensembles are subsequently introduced. How to choose algorithms to address common issues as well as methods for pre-clustering data processing, clustering evaluation and validation are then discussed. Importantly, we also provide general guidance on clustering workflow and reporting requirements. To facilitate the implementation of different algorithms, we provide information on R functions and libraries.


Asunto(s)
Algoritmos , Salud Mental , Humanos , Análisis por Conglomerados
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