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1.
ACS Nano ; 18(20): 13298-13307, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38727530

RESUMEN

As a second-order nonlinear optical phenomenon, the bulk photovoltaic (BPV) effect is expected to break through the Shockley-Queisser limit of thermodynamic photoelectron conversion and improve the energy conversion efficiency of photovoltaic cells. Here, we have successfully induced a strong flexo-photovoltaic (FPV) effect, a form of BPV effect, in strained violet phosphorene nanosheets (VPNS) by utilizing strain engineering at the h-BN nanoedge, which was first observed in nontransition metal dichalcogenide (TMD) systems. This BPV effect was found to originate from the disruption of inversion symmetry induced by uniaxial strain applied to VPNS at the h-BN nanoedge. We have revealed the intricate relationship between the bulk photovoltaic effect and strain gradients in VPNS through thickness-dependent photovoltaic response experiments. A bulk photovoltaic coefficient of up to 1.3 × 10-3 V-1 and a polarization extinction ratio of 21.6 have been achieved by systematically optimizing the height of the h-BN nanoedge and the thickness of VPNS, surpassing those of reported TMD materials (typically less than 3). Our results have revealed the fundamental relationship between the FPV effect and the strain gradients in low-dimensional materials and inspired further exploration of optoelectronic phenomena in strain-gradient engineered materials.

2.
ACS Omega ; 9(20): 22285-22295, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38799323

RESUMEN

In the western Junggar Basin, various oil and gas phases, such as black oil, volatile oil, condensate, and gas, have been discovered and reported. However, the primary factors responsible for the variations in oil and gas phases in different regions of the basin are not yet clearly understood. This study uses geochemical analyses, numerical simulations, and geological analyses to determine the extent of gas invasion in different regions, simulate the mechanism of gas invasion altering phase behavior, and shed light on its significant impact on fluid phases in hydrocarbons across diverse regions. The results show that the phase states of deep-seated fluids vary regionally, which is characterized by a gradual change from black oil to volatile oil, condensate, and gas from the northwest to the southeast. Gas invasion varies across oil reservoirs in different regions: the northwest regions show no significant gas invasion, the middle regions have a slight to moderate gas invasion, and the southeast regions exhibit the strongest gas invasion from heavy to severe. Varied degrees of gas invasion and corresponding phase transition rates, dependent on the gas dryness coefficient, are the primary causes of hydrocarbon fluid phase variations.

3.
ACS Nano ; 17(16): 16230-16238, 2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37530588

RESUMEN

Twisted van der Waals structures exhibit a variety of unusual electrical and optical phenomena and could provide a powerful means for designing nanodevices with tunable chiral properties. However, programming intrinsic chiral properties of the film on the atomic scale remains a great challenge due to the limitations of fabrication and measurement techniques. Here, we report a highly tunable large optical activity of twisted anisotropic two-dimensional (2D) materials, including black phosphorus (BP), ReS2, PdSe2, and α-MoO3, by varying the twist angle between the stacked layers. The chirality can be deliberately tailored through the engineering of the symmetry, band structure, and anisotropy of 2D materials, demonstrating the high tunability of the chirality. The results show the highest thickness-normalized ellipticity value (13.8 deg µm-1, twisted ReS2) and ellipticity value (1581 mdeg, twisted BP) among the systems based on 2D materials. It is also shown that the chiroptical response exists in an extremely large spectral range from the visible to the infrared. Furthermore, the twisted ReS2 enabled spin-selective control of the information transformation. These results show that highly controllable chirality in twisted 2D anisotropic materials has considerable potential in on-chip polarization optics, nano-optoelectronics, and biology.

4.
Surg Laparosc Endosc Percutan Tech ; 32(5): 542-548, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-35960700

RESUMEN

BACKGROUND: Laparoscopic left-sided hepatectomy (LLH) and additional biliary tract exploration are effective methods to treat left-sided hepatolithiasis (LSH) combined with extrahepatic bile duct stones. Although biliary tract exploration through common bile duct (CBD) incision has been widely accepted, the safety and effectiveness of the left hepatic duct (LHD) orifice approach after LLH is still in debate. METHODS: One hundred and forty-four patients with LSH who underwent LLH and biliary tract exploration in our institution from April 2014 to September 2021 were enrolled in the retrospectively study. They were divided into 3 groups: LHD group (n=67), CBD/T-tube group (n=58), and CBD/PC group (n=19). Patients' demographic characteristics, intraoperative, and postoperative outcomes were retrospectively analyzed. RESULTS: LHD group exhibited a shorter operative time (202.8±42.2 vs. 232.7±47.5 min, P =0.000), time to first bowel movement (2.3±0.5 vs. 2.9±0.7 d, P =0.000) and postoperative hospital stay (7.5±2.1 vs. 9.8±5.2 d, P =0.001) compared with the CBD/T-tube group. The lithotomy time in the LHD group was significantly longer than that in the CBD/T-tube group (33.6±7.3 vs. 29.0±6.3 min, P =0.000) and CBD/PC group (33.6±7.3 vs. 28.7±3.7, P =0.006). Intraoperative blood loss, blood transfusion rate, initial stone clearance rate, and stone recurrence rate all had no significant differences between the 3 groups (all P >0.05). LHD group showed less rate of electrolyte imbalance than that of the CBD/T-tube group (3.0% vs. 19.0%, P =0.004) but it was equivalent to the CBD/PC group ( P >0.05). The type of biliary tract exploration (odds ratio: 5.43, 95% confidence interval: 0.04-0.95, P =0.032) as independent predictors of electrolyte imbalance. No reoperation and mortality occurred in the 3 groups. The conversion rate was comparable among 3 groups (1.5% vs. 1.7% vs. 0, all P >0.05). No significant difference in stone recurrence rate was seen (1.5% vs. 3.4% vs. 0, all P >0.05). CONCLUSION: Biliary tract exploration through LHD orifice after LLH is a safe and effective treatment for selected patients with LSH, with an advantage over the T-tube drainage in the field of operative time, the incidence of electrolyte imbalance, recovery of gastrointestinal function, and postoperative hospital stay.


Asunto(s)
Coledocolitiasis , Laparoscopía , Litiasis , Hepatopatías , Coledocolitiasis/cirugía , Conducto Colédoco/cirugía , Electrólitos , Hepatectomía/métodos , Conducto Hepático Común/cirugía , Humanos , Laparoscopía/métodos , Tiempo de Internación , Litiasis/complicaciones , Litiasis/cirugía , Hepatopatías/cirugía , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Estudios Retrospectivos
5.
Front Oncol ; 12: 877376, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35712476

RESUMEN

Background: Circular RNAs (circRNAs) are a novel type of non-coding RNA, play an important role in the progression of tumors. However, the function and mechanism of circRNAs in regulating immune microenvironment of pancreatic cancer (PC) remain largely unclear. Methods: The effects of hsa_circ_0046523 expression on proliferation, migration and invasion of PC cells were analyzed by CCK8 and Transwell assays. Flow cytometry was used to detect the proportion of CD4+ T cells, CD8+ T cells and Tregs in peripheral blood mononuclear cells (PBMCs) after co-culture, and the apoptosis, depletion and function of CD8+ T cells. The expression levels of immunoregulatory cytokines were detected by enzyme linked immunosorbent assay (ELISA). The dual-luciferase reporter was performed to determine the interaction between hsa_circ_0046523, miR-148a-3p, and PD-L1. Rescue experiments and PD-L1 blocking experiments were employed to investigate whether hsa_circ_0046523 exerts its biological function by miR-148a-3p/PD-L1 in PC. Furthermore, an immunocompetent murine PC model was established to confirm these findings. Results: Hsa_circ_0046523 expression was remarkably upregulated in PC tissues and cell lines. Moreover, high expression of hsa_circ_0046523 was correlated with advanced pathological stage and poorer prognosis. Hsa_circ_0046523 overexpression promoted the proliferation, migration and invasion of PC cells in vitro. Co-culture experiments confirmed that forced expression of hsa_circ_0046523 could decrease the proportion of CD4+ and CD8+ T cells, as well as increase the proportion of Tregs among peripheral blood mononuclear cells (PBMCs). Meanwhile, hsa_circ_0046523 overexpression promoted the apoptosis and exhaustion of CD8+ T cells, inhibited CD8+ T cell function, increased the secretion of immunosuppressive cytokines IL-10 and TGF-ß, and decreased the secretion of immune effector cytokines IFN-γ and IL-2 among PBMCs. Mechanistically, hsa_circ_0046523 exerted its biological function by binding to miR-148a-3p to upregulate PD-L1 expression in PC. Moreover, these immune modulating functions of miR-148a-3p/PD-L1 axis were also confirmed in an immunocompetent murine PC model. Conclusions: Our study suggests that hsa_circ_0046523/miR-148a-3p/PD-L1 regulatory axis mediates PC immunosuppressive microenvironment and these molecules are expected to be new targets for remodeling tumor immune microenvironment of PC.

6.
Med Sci Monit ; 28: e935685, 2022 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-35398875

RESUMEN

BACKGROUND Pancreaticoduodenectomy (PD) and distal pancreatectomy with splenectomy (DPS) are considered the standard procedures for pancreatic lesions. However, long-term metabolic consequences of PD and DPS applied for benign or low-grade malignant tumors need to be addressed. This study aimed to investigate the short- and long-term outcomes of organ-sparing pancreatectomy for benign or low-grade malignant pancreatic tumors in our institution. MATERIAL AND METHODS The clinical data of 101 patients with benign or low-grade malignant pancreatic tumors who underwent organ-sparing pancreatectomy from January 2009 to September 2021 were retrospectively analyzed, including 40 tumor enucleations (EN), 22 central pancreatectomies (CP), 25 spleen-preserving distal pancreatectomies (SPDP), 7 pylorus-preserving pancreaticoduodenectomies (PPPD) and 7 duodenum-preserving pancreatic head resections (DPPHR). RESULTS The mean operative time, intraoperative blood loss, and length of hospital stay were 182.9±74.6 min, 191.9±127.8 mL, and 11.6±8.1 days, respectively. EN had the shortest operative time, while DPPHR had the longest operative time. The mean intraoperative blood loss of DPPHR and PPPD was significantly greater than the others (all P<0.05). The length of hospital stay of PPPD was longest. The overall morbidity was 33.6%. The reoperation rate was 1.0% and there was no mortality. The incidence of pancreatic endocrine insufficiency and exocrine insufficiency were 5.9% and 6.9%, respectively. None patients had tumor recurrence during the follow-up period. CONCLUSIONS Organ-sparing pancreatectomy is associated with acceptable perioperative risk and postoperative complications and better long-term outcomes in the aspects of preservation of function and curability in benign or low-grade malignant pancreatic tumors.


Asunto(s)
Pancreatectomía , Neoplasias Pancreáticas , Pérdida de Sangre Quirúrgica , Humanos , Recurrencia Local de Neoplasia/cirugía , Pancreatectomía/métodos , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Complicaciones Posoperatorias/cirugía , Estudios Retrospectivos , Resultado del Tratamiento
7.
BMC Oral Health ; 22(1): 31, 2022 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-35120518

RESUMEN

INTRODUCTION: The aim was to analyze the morphological changes of root apex in anterior teeth with periapical periodontitis. METHODS: 32 untreated anterior teeth with periapical periodontitis were enrolled, compared with the healthy contralateral teeth. Two-dimensional measurement of Cone-beam computed tomography was used to determine the location and measure diameter of the apical constriction according to Schell's methods. An open-source software (3D Slicer) was used to reconstruct the teeth. The apical constriction form was analysis according to Schell's topography. The distances of apical constriction to apical foramen and anatomical apex were measured respectively. RESULTS: The difference value between buccolingual and mesiodistal diameter was (0.06 ± 0.09) mm and (0.04 ± 0.04) mm in periapical periodontitis and controls (p < 0.05). The mean distance between apical constriction and anatomical apex was significantly shorter in periapical periodontitis than controls, so was the mean distance of apical constriction to apical foramen. The most common form of apical constriction was flaring (65.6%) in periapical periodontitis. CONCLUSIONS: The anterior teeth with periapical periodontitis had shorter distances of apical constriction to anatomical apex and apical foramen, bigger disparities between the diameters of buccolingual and mesiodistal, and higher proportion of flaring apical constriction.


Asunto(s)
Periodontitis Periapical , Tomografía Computarizada de Haz Cónico , Humanos , Periodontitis Periapical/complicaciones , Periodontitis Periapical/diagnóstico por imagen , Tratamiento del Conducto Radicular/métodos , Ápice del Diente/diagnóstico por imagen
8.
J Cell Mol Med ; 24(22): 13020-13035, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33026174

RESUMEN

Although miR-148a-3p has been reported to function as a tumour suppressor in various cancers, the molecular mechanism of miR-148a-3p in regulating epithelial-to-mesenchymal transition (EMT) and stemness properties of pancreatic cancer (PC) cells remains to be elucidated. In the present study, we demonstrated that miR-148a-3p expression was remarkably down-regulated in PC tissues and cell lines. Moreover, low expression of miR-148a-3p was associated with poorer overall survival (OS) in patients with PC. In vitro, gain-of-function and loss-of-function experiments showed that miR-148a-3p suppressed EMT and stemness properties as well as the proliferation, migration and invasion of PC cells. A dual-luciferase reporter assay demonstrated that Wnt1 was a direct target of miR-148a-3p, and its expression was inversely associated with miR-148a-3p in PC tissues. Furthermore, miR-148a-3p suppressed the Wnt/ß-catenin pathway via down-regulation of Wnt1. The effects of ectopic miR-148a-3p were rescued by Wnt1 overexpression. These biological functions of miR-148a-3p in PC were also confirmed in a nude mouse xenograft model. Taken together, these findings suggest that miR-148a-3p suppresses PC cell proliferation, invasion, EMT and stemness properties via inhibiting Wnt1-mediated Wnt/ß-catenin pathway and could be a potential prognostic biomarker as well as a therapeutic target in PC.


Asunto(s)
Transición Epitelial-Mesenquimal , MicroARNs/metabolismo , Células Madre Neoplásicas/metabolismo , Neoplasias Pancreáticas/metabolismo , Vía de Señalización Wnt , Proteína Wnt1/metabolismo , Animales , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Invasividad Neoplásica , Trasplante de Neoplasias , beta Catenina/metabolismo
9.
J Pet Explor Prod Technol ; 7(3): 699-706, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28868213

RESUMEN

With the constant consumption of conventional oil and gas resources, unconventional oil and gas resources with great resource potential such as tight oil have gradually been valued and become the new exploration area. Jimsar Sag is the key tight oil exploration and development block in Junggar Basin of Northwestern China. Based on the data sets of geology, oil production test, logging, rock thin section, and geochemistry of Permian Lucaogou Formation (LCG), we studied the geochemical characteristics of hydrocarbon source rocks and their relation to the tight oil accumulation. Organic matter abundance of source rocks is high, the types of organic matter are mainly type I and type II, and the organic matter maturation is in the low mature stage to mature stage. Results of oil source correlation showed that the crude oil of sweet spots was mainly derived from the source rocks in the interior of the sweet spots. The LCG tight oil is mainly distributed in the plane where the source rocks have great thickness and the TOC is higher than 3.5%. It shows that the source rocks have obvious controlling on the occurrence and accumulation of tight oil.

10.
Chin Med J (Engl) ; 130(2): 199-202, 2017 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-28091412

RESUMEN

BACKGROUND: Although that glomerulonephritis is the major cause of end-stage renal disease in developing countries such as China, the increasing prevalence of diabetes has contributed to the changing spectrum of predialysis chronic kidney disease. Recent studies have revealed an increased proportion of patients with diabetic kidney disease (DKD) in hemodialysis populations in large cities in China. However, studies regarding the clinical phenotype of DKD in China are extremely limited. The incidence, development, and prognosis of diabetic kidney disease (INDEED) study aims to investigate the incidence, progression, and prognosis of DKD, as well as the associated genetic, behavioral, and environmental factors and biomarkers in patients with DKD in China. METHODS: INDEED study is a prospective cohort study based on all participants with diabetes in the Kailuan study, which is a general population-based cohort study in northern China. Altogether, over 10,000 participants with diabetes will be followed biennially. Questionnaires documenting general characteristics, behavioral and environmental factors, and medical history will be administrated. Anthropometric measurements and a series of laboratory tests will be performed in one central laboratory. The DNA, plasma, and urine samples of every participant will be stored in a biobank for future research. CONCLUSIONS: INDEED study will provide essential information regarding the clinical phenotype and prognosis of patients with DKD in China and will be valuable to identify factors and biomarkers associated with patients with DKD in China.


Asunto(s)
Nefropatías Diabéticas/epidemiología , Biomarcadores , China/epidemiología , Nefropatías Diabéticas/patología , Femenino , Humanos , Incidencia , Masculino , Pronóstico , Estudios Prospectivos , Encuestas y Cuestionarios
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(10): 2639-42, 2011 Oct.
Artículo en Chino | MEDLINE | ID: mdl-22250524

RESUMEN

In recent years, spectral imaging technique has been applied widely in mineralogy and petrology. The technique combines the spectral technique with imaging technique. The samples can be analyzed and recognized both in spectra and space by using the technique. However, the problem is how to acquire the needful information from a large number of data of spectral imaging, and how to enhance the needful information. In the present paper, the experimental data were processed by using the technique of data fusion of microscopic spectral imaging. The space distribution map of chemical composition and physical parameters of samples were obtained. The result showed that the distribution of different hydrocarbon in the reservoirs, pore connectivity, etc. were revealed well. The technique of data fusion of microscopic spectral imaging provided a new method for reservoir characterization.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(9): 2397-400, 2010 Sep.
Artículo en Chino | MEDLINE | ID: mdl-21105404

RESUMEN

In the present paper, the authors examined some inclusions of carbonate reservoir by microscopic confocal Raman spectral methods. The measurement temperature of sample was 18 degrees C, -40 degrees C, -80 degrees C and -170 degrees C, respectively. The experimental results show that the original experimental spectral curve of the inclusion was very similar to the original experimental spectral curve of pure main mineral (rock core). Because the size of some inclusions was relatively small or inclusions were hid den deeply in the sample, their Raman spectra signals were often buried in other signals (noises) which stem from main mineral. To overcome the above-mentioned difficulty we used the spectral subtraction method. In Raman spectral experimental process, X-Y scanning and depth profile (Z scanning) were finished around the inclusion. The final results show that spectral subtraction method allows the study of solid samples with high precision because some corrections can be made, if additive properties of spectral quantity are satisfied. Interfering spectral signal from main mineral can be removed, and the inclusion spectrum can be purified.

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