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1.
Artículo en Inglés | MEDLINE | ID: mdl-39291353

RESUMEN

Objective: To evaluate the operative outcome of the use of intracavitary retractors in transumbilical laparoendoscopic single-site (LESS) adrenalectomy in comparison with the conventional multiport laparoendoscopic procedure. Methods: Between July 2021 and December 2023, 34 patients underwent transumbilical LESS adrenalectomy with intracavitary retractors, while 47 patients underwent conventional multiport laparoscopic adrenalectomy. Comprehensive data were compared, including demographics, intraoperative outcomes, perioperative complications, postoperative visual analog pain scale score, analgesic requirement, and short-term measures of convalescence. Results: Baseline characteristics were similar between the groups. All procedures were successfully completed without additional access or open conversion. The mean operative time and estimated blood loss for LESS adrenalectomy were comparable with multiport adrenalectomy. The LESS group had significantly shorter incision length (3.07 cm versus 5.16 cm, P < .01), lower postoperative pain scores (3.29 versus 4.91, P < .01), less analgesic drug use (29% versus 53%, P = .03), and better cosmetic scores (9.29 versus 7.28, P < .01). No significant differences were observed in time to resume oral intake, time to ambulation, or postoperative hospital stay. Complication rates were similar between the groups. Conclusion: The utilization of intracavitary retractors in transumbilical LESS adrenalectomy has demonstrated feasibility, effectiveness, and the potential to reduce technical complexities with satisfactory cosmetic effects. This technique enhances visualization of the surgical field without the need for extra ports.

2.
Medicine (Baltimore) ; 103(31): e39176, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39093776

RESUMEN

This study aimed to identify novel biomarkers associated with cuproptosis in human nonobstructive azoospermia (NOA). We obtained 4 NOA microarray datasets (GSE145467, GSE9210, GSE108886, and GSE45885) from the NCBI Gene Expression Omnibus database and merged them into training set. Another NOA dataset (GSE45887) was used as validation set. Differentially expressed cuproptosis-related genes were identified from training set. Gene Ontology function and Kyoto Encyclopedia of Genes and Genomes pathway analyses were conducted. Least absolute shrinkage and selection operator regression and support vector machine-recursive feature elimination were used to identify hub cuproptosis-related genes. We calculated the expression of the hub cuproptosis-related genes in both validation set and patients with NOA. Gene set variation analysis was used to explore their potential biological functions. The risk prediction model was built by logistic regression analysis and was evaluated in the validation set. Finally, we constructed a competing endogenous RNA network. The training set included 29 patents in the control group and 92 in the NOA group, and 10 cuproptosis-related differentially expressed genes were identified. Subsequently, we screened 6 hub cuproptosis-related genes (DBT, GCSH, NFE2L2, NLRP3, PDHA1, and SLC31A1) by least absolute shrinkage and selection operator regression and support vector machine-recursive feature elimination. GCSH, NFE2L2, NLRP3, and SLC31A1 expressed higher in NOA group than in control group (P < .05) in the validation set (4 patients in control and 16 in NOA groups), while the expression levels of GCSH, NFE2L2, NLRP3, PDHA1, and SLC31A1 were higher in NOA group than in control group (P < .05) in our patients (3 patients in control and 4 in NOA groups). The model based on the 6-gene signature showed superior performance with an AUC value of 0.970 in training set, while 1.0 in validation set. Gene set variation analysis revealed a higher enrichment score of "homologous recombination" in the high expression groups of the 6 hub genes. Finally, we constructed a competing endogenous RNA network and found hsa-miR-335-3p and hsa-miR-1-3p were the most frequently related to the 6 hub genes. DBT, GCSH, NFE2L2, NLRP3, PDHA1, and SLC31A1 may serve as predictors of cuproptosis and play important roles in the NOA pathogenesis.


Asunto(s)
Azoospermia , Humanos , Masculino , Azoospermia/genética , Perfilación de la Expresión Génica/métodos , Bases de Datos Genéticas , Biomarcadores/metabolismo , Máquina de Vectores de Soporte , Ontología de Genes
3.
Anal Chem ; 96(12): 4860-4867, 2024 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-38478499

RESUMEN

Bladder cancer (BC) occurrence and progression are accompanied by alterations in microRNAs (miRNAs) expression levels. Simultaneous detection of multiple miRNAs contributes to the accuracy and reliability of the BC diagnosis. In this work, wrinkled silica nanoparticles (WSNs) were applied as the microreactor for multiplex miRNAs analysis without enzymes or nucleic acid amplification. Conjugated on the surface of WSNs, the S9.6 antibody was adopted as the universal module for binding DNA/miRNA duplexes, regardless of their sequence. Furthermore, single-stranded DNA (ssDNA) was labeled with quantum dots (QDs) for identifying a given miRNA to form QDs-ssDNA/miRNA, which enabled the specific capture of the corresponding QDs on the wrinkled surface of WSNs. Based on the detection of fluorescence signals that were ultimately focused on WSNs, target miRNAs could be sensitively identified to a femtomolar level (5 fM) with a wide dynamic range of up to 6 orders of magnitude. The proposed strategy achieved high specificity to obviously distinguish single-base mutation sequences and possessed multiplex assay capability. Moreover, the assay exhibited excellent practicability in the multiplex detection of miRNAs in clinical serum specimens.


Asunto(s)
Técnicas Biosensibles , MicroARNs , Puntos Cuánticos , Neoplasias de la Vejiga Urinaria , Humanos , MicroARNs/análisis , Reproducibilidad de los Resultados , ADN , ADN de Cadena Simple , Neoplasias de la Vejiga Urinaria/diagnóstico , Neoplasias de la Vejiga Urinaria/genética
4.
Aging (Albany NY) ; 16(6): 5387-5411, 2024 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-38484140

RESUMEN

Prostate cancer (PCa) is a common malignancy in elderly men. We have applied Traditional Chinese Medicine CFF-1 in clinical treatments for PCa for several years. Here, we aimed to identify the underlying mechanism of CFF-1 on PCa using network pharmacology and experimental validation. Active ingredients, potential targets of CFF-1 were acquired from the public databases. Subsequently, protein-protein interaction (PPI) and the herbs-active ingredients-target network was constructed. A prognostic model for PCa was also constructed based on key targets. In vitro experiments using PCa cell lines CWR22Rv1 and PC-3 were carried out to validate the potential mechanism of CFF-1 on PCa. A total of 112 bioactive compounds and 359 key targets were screened from public databases. PPI and herbs-active ingredients-target network analysis determined 12 genes as the main targets of CFF-1 on PCa. Molecular docking studies indicated that the primary active ingredients of CFF-1 possess strong binding affinity to the top five hub targets. DNMT3B, RXRB and HPRT1 were found to be involved in immune regulation of PCa. In vitro, CFF-1 was found to inhibit PCa cell proliferation, migration, invasion and induce apoptosis via PI3K-Akt, HIF-1, TNF, EGFR-TKI resistance and PD-1 checkpoint signaling pathways. This study comprehensively elucidates the underlying molecular mechanism of CFF-1 against PCa, offering a strong rationale for clinical application of CFF-1 in PCa treatment.


Asunto(s)
Farmacología en Red , Neoplasias de la Próstata , Anciano , Masculino , Humanos , Medicina Tradicional China , Simulación del Acoplamiento Molecular , Fosfatidilinositol 3-Quinasas , Neoplasias de la Próstata/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-akt
5.
Sensors (Basel) ; 23(24)2023 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-38139713

RESUMEN

The accurate measurement of soil organic matter (SOM) is vital for maintaining soil quality. We present an innovative model for SOM prediction by integrating spectral and profile features. We use PCA, Lasso, and SCARS methods to extract important spectral features and combine them with profile data. This hybrid approach significantly improves SOM prediction across various models, including Random Forest, ExtraTrees, and XGBoost, boosting the coefficient of determination (R2) by up to 26%. Notably, the ExtraTrees model, enriched with PCA-extracted features, achieves the highest accuracy with an R2 of 0.931 and an RMSE of 0.068. Compared with single-feature models, this approach improves the R2 by 17% and 26% for PCA features of full-band spectra and profile features, respectively. Our findings highlight the potential of feature integration, especially the ExtraTrees model with PCA-extracted features and profile features, as a stable and accurate tool for SOM prediction in extensive study areas.

6.
Front Immunol ; 14: 1207061, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37662929

RESUMEN

Background: Immunogenic cell death (ICD) is considered a particular cell death modality of regulated cell death (RCD) and plays a significant role in various cancers. The connection between kidney renal clear cell carcinoma (KIRC) and ICD remains to be thoroughly explored. Methods: We conducted a variety of bioinformatics analyses using R software, including cluster analysis, prognostic analysis, enrichment analysis and immune infiltration analysis. In addition, we performed Quantitative Real-time PCR to evaluate RNA levels of specific ICD genes. The proliferation was measured through Cell Counting Kit-8 (CCK-8) assay and colony-formation assay in RCC cell lines. Results: We determined two ICD subtypes through consensus clustering analysis. The two subtypes showed significantly different clinical outcomes, genomic alterations and tumor immune microenvironment. Moreover, we constructed the ICD prognostic signature based on TF, FOXP3, LY96, SLC7A11, HSP90AA1, UCN, IFNB1 and TLR3 and calculated the risk score for each patient. Kaplan-Meier survival analysis and ROC curve demonstrated that patients in the high-risk group had significantly poorer prognosis compared with the low-risk group. We then validated the signature through external cohort and further evaluated the relation between the signature and clinical features, tumor immune microenvironment and immunotherapy response. Given its critical role in ICD, we conducted further analysis on LY96. Our results indicated that downregulation of LY96 inhibited the proliferation ability of RCC cells. Conclusions: Our research revealed the underlying function of ICD in KIRC and screened out a potential biomarker, which provided a novel insight into individualized immunotherapy in KIRC.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/terapia , Muerte Celular Inmunogénica , Pronóstico , Inmunoterapia , Neoplasias Renales/genética , Neoplasias Renales/terapia , Riñón , Microambiente Tumoral
7.
Biomimetics (Basel) ; 8(4)2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37622946

RESUMEN

In this paper, the ballistic performance of a multilayered composite inspired by the structural characteristics of nacre is numerically investigated using finite element (FE) simulations. Nacre is a natural composite material found in the shells of some marine mollusks, which has remarkable toughness due to its hierarchical layered structure. The bioinspired nacre-like composites investigated here were made of five wavy aluminum alloy 7075-T651 (AA7075) layers composed of ~1.1-mm thick square tablets bonded together with toughened epoxy resin. Two composite configurations with continuous layers (either wavy or flat) were also studied. The ballistic performance of the composite plates was compared to that of a bulk monolithic AA7075 plate. The ballistic impact was simulated in the 300-600 m/s range using two types of spherical projectiles, i.e., rigid and elastoplastic. The results showed that the nacre plate exhibited improved ballistic performance compared to the bulk plate and the plates with continuous layers. The structural design of the nacre plate improved the ballistic performance by producing a more ductile failure and enabling localized energy absorption via the plastic deformation of the tablets and the globalized energy dissipation due to interface debonding and friction. All the plate configurations exhibited a better ballistic performance when impacted by an elastoplastic projectile compared to a rigid one, which is explained by the projectile plastic deformation absorbing some of the impact energy and the enlarged contact area between the projectile and the plates producing more energy absorption by the plates.

8.
Sci Rep ; 13(1): 3844, 2023 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-36890206

RESUMEN

This study aimed to compare the peri- and postoperative outcomes of patients treated with conventional versus robot-assisted laparoendoscopic single-site radical prostatectomy (C-LESS-RP vs. R-LESS-RP). Data of patients with prostate cancer (106 who underwent C-LESS-RP, 124 underwent R-LESS-RP) were retrospectively collected and analyzed. All operations were performed by the same surgeon from January 8, 2018, to January 6, 2021, in the same institution. Information on clinical characteristics and perioperative outcomes was obtained from records at the medical institution. Postoperative outcomes were acquired from follow-up. Intergroup differences were retrospectively analyzed and compared. All patients had similar clinical characteristics in meaningful aspects. The perioperative outcomes were better with R-LESS-RP than with C-LESS-RP in terms of operation time (120 min vs. 150 min, p < 0.05), estimated blood loss (17.68 ml vs. 33.68 ml, p < 0.05), and analgesic duration (0 days vs. 1 days, p < 0.05). The drainage tube duration and postoperative stay did not differ significantly between groups. However, R-LESS-RP was more expensive than C-LESS-RP (56559.510 CNY vs. 44818.27 CNY, p < 0.05). The patients who underwent R-LESS-RP had better urinary incontinence recovery and higher European quality of life visual analog scale scores than those who underwent C-LESS-RP. However, no significant intergroup difference was noted in biochemical recurrence. In conclusion, R-LESS-RP could achieve better perioperative outcomes, especially for those skilled surgeons who have mastered C-LESS-RP. Additionally, R-LESS-RP accelerated the recovery from urinary incontinence effectively and presented some benefits in health-related quality of life with additional costs.


Asunto(s)
Neoplasias de la Próstata , Incontinencia Urinaria , Masculino , Humanos , Estudios Retrospectivos , Resultado del Tratamiento , Calidad de Vida , Incontinencia Urinaria/etiología , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/etiología , Prostatectomía/efectos adversos
11.
Sci Rep ; 12(1): 3017, 2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35194067

RESUMEN

Describing the material flow stress and the associated uncertainty is essential for the plastic stochastic structural analysis. In this context, a data-driven approach-heteroscedastic sparse Gaussian process regression (HSGPR) with enhanced efficiency is introduced to model the material flow stress. Different from other machine learning approaches, e.g. artificial neural network (ANN), which only estimate the deterministic flow stress, the HSGPR model can capture the flow stress and its uncertainty simultaneously from the dataset. For validating the proposed model, the experimental data of the Al 6061 alloy is used here. Without setting a priori assumption on the mathematical expression, the proposed HSGPR-based flow stress model can produce a better prediction of the experimental stress data than the ANN model, the conventional GPR model, and Johnson Cook model at elevated temperatures. After the HSGPR-based flow stress model is implemented into finite element analysis, two numerical examples with synthetic material properties are performed to demonstrate the model's capability in stochastic plastic structural analysis. The results have shown that with sufficient data, the distribution of the structural load carrying capacity at elevated temperatures and the variation of load-displacement curves during the loading and unloading processes can be accurately predicted by the HSGPR-based flow stress model.

12.
Materials (Basel) ; 14(11)2021 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-34204967

RESUMEN

Pre-existing cracks and associated filling materials cause the significant heterogeneity of natural rocks and rock masses. The induced heterogeneity changes the rock properties. This paper targets the gap in the existing literature regarding the adopting of artificial neural network approaches to efficiently and accurately predict the influences of heterogeneity on the strength of 3D-printed rocks at different strain rates. Herein, rock heterogeneity is reflected by different pre-existing crack and filling material configurations, quantitatively defined by the crack number, initial crack orientation with loading axis, crack tip distance, and crack offset distance. The artificial neural network model can be trained, validated, and tested by finite 42 quasi-static and 42 dynamic Brazilian disc experimental tests to establish the relationship between the rock strength and heterogeneous parameters at different strain rates. The artificial neural network architecture, including the hidden layer number and transfer functions, is optimized by the corresponding parametric study. Once trained, the proposed artificial neural network model generates an excellent prediction accuracy for influences of high dimensional heterogeneous parameters and strain rate on rock strength. The sensitivity analysis indicates that strain rate is the most important physical quantity affecting the strength of heterogeneous rock.

13.
Materials (Basel) ; 14(13)2021 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-34202545

RESUMEN

Unusual force constants originating from the local charge distribution in crystalline GeTe and Sb2Te3 are observed by using the first-principles calculations. The calculated stretching force constants of the second nearest-neighbor Sb-Te and Ge-Te bonds are 0.372 and -0.085 eV/Å2, respectively, which are much lower than 1.933 eV/Å2 of the first nearest-neighbor bonds although their lengths are only 0.17 Å and 0.33 Å longer as compared to the corresponding first nearest-neighbor bonds. Moreover, the bending force constants of the first and second nearest-neighbor Ge-Ge and Sb-Sb bonds exhibit large negative values. Our first-principles molecular dynamic simulations also reveal the possible amorphization of Sb2Te3 through local distortions of the bonds with weak and strong force constants, while the crystalline structure remains by the X-ray diffraction simulation. By identifying the low or negative force constants, these weak atomic interactions are found to be responsible for triggering the collapse of the long-range order. This finding can be utilized to guide the design of functional components and devices based on phase change materials with lower energy consumption.

14.
J Laparoendosc Adv Surg Tech A ; 31(1): 90-94, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33185514

RESUMEN

Objective: To compare the surgical and early oncological outcomes in patients with bladder cancer who had laparoendoscopic single-site radical cystectomy (RC) or laparoscopic RC. Materials and Methods: From July 2012 to May 2019, 28 consecutive men suffering from bladder cancer underwent laparoendoscopic single-site RC or laparoscopic RC with extracorporeally ileal conduit diversion. Data regarding the patient characteristics, surgical outcomes, and short-term oncological outcomes were analyzed retrospectively. Results: Compared with laparoscopic RC, laparoendoscopic single-site RC was associated with less postoperative pain (mean, 4.67 versus 6.08 scores; P = .004), and shorter convalescence (time to ambulation, mean, 1.13 days versus 2.15 days; P = .000; hospital stay after surgery, mean, 13 days versus 19 days; P = .001). In addition, differences in patient characteristics, mean total operation time, and mean estimated blood loss were not statistically significant between laparoendoscopic single-site RC and laparoscopic RC groups. There was no difference in the early or late complication rate between the two groups as well. It is also revealed that there was no significant difference in the overall survival rate at 24 months between laparoendoscopic single-site RC and laparoscopic RC groups. Conclusions: Based on our initial experience with laparoendoscopic single-site RC, it is a safe procedure with acceptable complications and oncological outcomes. Notably, laparoendoscopic single-site RC is associated with less postoperative pain and rapider convalescence compared with the historical series of laparoscopic RC. However, further comparative studies with longer follow-up period are warranted to validate this procedure.


Asunto(s)
Cistectomía/métodos , Laparoscopía/métodos , Neoplasias de la Vejiga Urinaria/cirugía , Anciano , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Tempo Operativo , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/mortalidad , Derivación Urinaria/métodos
15.
Int Urol Nephrol ; 53(2): 249-255, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32902797

RESUMEN

PURPOSE: To describe our initial experience with laparoendoscopic radical prostatectomy (LRP) and a stepwise transition towards transurethral assisted laparoendoscopic single-site RP (TU-LESS RP). PATIENTS AND METHODS: From Jan. 2007 to Dec. 2016, 195 patients underwent RP, of which 89 patients were performed by LRP (Group A), 106 by TU-LESS RP (Group B). The peri-operative data were collected and analyzed. All data referring to patient demographics, surgery, pathology, and peri-operative outcomes were recorded. The cosmetic result was investigated by the Patient Scar Assessment Questionnaire (PSAQ). Analysis of variance or Chi squared test were adopted to analyze the data. RESULTS: 195 procedures were completed successfully. The operation time (109.6 ± 31.9 vs. 151.5 ± 87.3, P = 0.025) and anastomosis time (10.1 ± 4.8 vs. 21.8 ± 9.9, P < 0.001) of Group B was significantly reduced compared with Group A. Estimated blood loss in Group B was significantly lower than that in Group A (95.9 ± 11.1 vs. 180.2 ± 99.7, P = 0.006). About perioperative complications, Group B was also less compared with Group A (1.9% vs. 7.9%, P = 0.047). As to the usage of postoperative analgesics, Group B apparently used less than that in Group A (6.6% vs. 62.9%, P < 0.001), which is consistent with the visual analogue scale (VAS) of the two groups (1.7 ± 1.3 vs. 7.8 ± 1.1, P < 0.001). Patients in Group B were significantly more satisfied with incision healing than in group A (74.9 ± 9.3 vs. 49.7 ± 5.8, P < 0.001). There was no significant difference both in BCR rate and time between Group B and Group A. In urination control, more patients in Group B did not have urinary incontinence 3 month after RP compared with Group A (81.1% vs. 67.4%, P = 0.028). CONCLUSIONS: LESS RP is proved to be feasible for the proper patients, but it is difficult to popularized due to inconvenient operation. While by means of TU-LESS, operating difficulty can be significantly decreased. TU-LESS RP will be wildly accepted by surgeons and patients because of cosmetic satisfaction and quicker recovery.


Asunto(s)
Laparoscopios , Laparoscopía/instrumentación , Laparoscopía/métodos , Prostatectomía/métodos , Neoplasias de la Próstata/cirugía , Anciano , Diseño de Equipo , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Uretra
16.
Materials (Basel) ; 13(20)2020 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-33081397

RESUMEN

Parent concrete coming from a wide range of sources can result in considerable differences in the properties of recycled coarse aggregate (RCA). In this study, the RCAs were obtained by crushing the parent concrete with water-to-cement ratios (W/Cparent) of 0.4, 0.5 and 0.6, respectively, and were strengthened by carbonation and nano-silica slurry wrapping methods. It was found that when W/Cparen was 0.3, 0.4 and 0.5, respectively, compared with the mortar in the untreated RCA, the capillary porosity of the mortar in the carbonated RCA decreased by 19%, 16% and 30%, respectively; the compressive strength of concrete containing the carbonated RCA increased by 13%, 11% and 13%, respectively; the chloride diffusion coefficient of RAC (DRAC) containing the nano-SiO2 slurry-treated RCA decreased by 17%, 16% and 11%; and that of RAC containing the carbonated RCA decreased by 21%, 25% and 26%, respectively. Regardless of being strengthened or not, both DRAC and porosity of old mortar in RCAs increased with increasing W/Cparent. For different types of RCAs, DRAC increased obviously with increasing water absorption of RCA. Finally, a theoretical model of DRAC considering the water absorption of RCA was established and verified by experiments, which can be used to predict the DRAC under the influence of different factors, especially the water absorption of RCA.

17.
Phys Rev E ; 99(4-1): 043109, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31108613

RESUMEN

In this study, using the Green-Kubo-method-based molecular dynamics simulations, correlations for predicting the thermophysical properties of nanofluids are developed based on particle shape, fluid temperature, and volume concentration. Silver nanofluids with various nanoparticle shapes including spheres, cubes, cylinders, and rectangular prisms are investigated. The numerical study is conducted within the concentration range 0.14-1.4 vol % and temperature range 280-335 K. The relative thermal conductivity and relative viscosity predicated by the proposed correlations are within a mean deviation of 2% and 5%, respectively, as compared with the experimental results from this study and the available literature. The proposed correlation will be a useful tool for engineers in designing the nanofluids for different applications in industry.

18.
Langmuir ; 35(15): 5324-5332, 2019 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-30869902

RESUMEN

The dynamic wetting for the CO2-water-silica system occurring in deep reservoirs is complex because of the interactions among multiple phases. This work aims to quantify the contact angle of CO2-water flow in the silica channel at six different flow velocities using molecular dynamics. The dynamic contact angle values at different contact line velocities are obtained for the CO2-water-silica system. By calculating the rates of the adsorption-desorption process of CO2 and water molecules on the silica surface using molecular dynamics simulations, it has been found that the results of the dynamic contact angle can be explained by the molecular kinetic theory and predicted from the equilibrium molecular simulations. Moreover, the capillary pressure at different contact line velocities is predicted according to the Young-Laplace equation. The change in contact angles at different velocities is compared with empirical equations in terms of capillary number. The results of this study can help us better understand the dynamic process of the multiphase flow at the nanoscale under realistic reservoir conditions.

19.
Int Urol Nephrol ; 51(3): 409-415, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30637594

RESUMEN

OBJECTIVES: To evaluate the feasibility and clinical efficacy of a novel intraabdominal retractor device in laparoendoscopic single-site nephrectomy(LESS-N). METHODS: Between February 2012 and February 2017, 98 patients underwent LESS-N in our institution, including 38 patients with benign renal disease and 60 patients with malignant renal disease. 39 were performed conventional LESS-N(C-LESS-N) and 59 were performed intraabdominal retractor-assisted LESS-N(IAR-LESS-N). Demographic data, and perioperative and postoperative data were collected and analyzed retrospectively. RESULTS: All the procedures were completed successfully. In C-LESS-N group, four patients were added one 5-mm additional trocar and two patients were converted to open surgery. In IAR-LESS-N group, no patients required additional trocars or conversion to open surgery. The mean operative time was lower in IAR-LESS-N group than that in C-LESS-N group (94.2 min vs 127.4 min, P < 0.05). The mean renal vascular management time declined from 25.4 min in C-LESS-N group to 18.4 min in IAR-LESS-N group (P < 0.05). The mean estimated blood loss was 128.6 ml in C-LESS-N group and 102.3 ml in IAR-LESS-N group (P < 0.05). Two patients in C-LESS-N group required blood transfusion, while none of the patients in IAR-LESS-N group did. No severe postoperative complications occurred in both groups. Study limitations included retrospective study, short follow-up, and accumulated surgical experience and skills. CONCLUSIONS: Intraabdominal retractors allow performance of LESS-N with improved working space, quicker renal hilar management, and shortened total operative time. It is expected that the application of intraabdominal retractors, along with the new robotic platform might revive LESS and translate into a renewed future interest of LESS.


Asunto(s)
Endoscopía/instrumentación , Enfermedades Renales/cirugía , Laparoscopía/instrumentación , Nefrectomía/instrumentación , Adulto , Anciano , Pérdida de Sangre Quirúrgica , Transfusión Sanguínea , Endoscopía/efectos adversos , Estudios de Factibilidad , Femenino , Humanos , Laparoscopía/efectos adversos , Masculino , Persona de Mediana Edad , Nefrectomía/efectos adversos , Nefrectomía/métodos , Tempo Operativo , Estudios Retrospectivos
20.
J Chem Phys ; 149(12): 124505, 2018 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-30278659

RESUMEN

The objective of this study is to develop and test a coarse-grained molecular dynamics framework to model microscale multiphase systems with different inter-particle interactions and recover emerging thermodynamic and mechanical properties at the microscale. A water-vapor model and a fused silica model are developed to demonstrate the capability of our framework. The former can reproduce the water density and surface tension over a wide range of temperatures; the latter can reproduce experimental density, tensile strength, and Young's modulus of fused silica. Therefore, the deformable solid model is implemented in the proposed framework. Validations of spatial scaling methods for solid, liquid, and multiphase systems suggest that the proposed framework can be calibrated at an arbitrary microscale and used at a different length scale without recalibration. Different values of wettability for a solid-liquid-vapor system that is characterized by the contact angle can be achieved by changing the solid-liquid inter-particle potential. Thanks to these features, the proposed coarse-grained molecular dynamics framework can potentially find applications in modeling systems in which multiple phases coexist and have substantial interactions.

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