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1.
Small ; : e2404215, 2024 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-38973090

RESUMEN

Aqueous nickel-ion batteries (ANIBs) as an emerging energy storage device attracted much attention owing to their multielectron redox reaction and dendrite-free Ni anode, yet their development is hindered by the divalent properties of Ni2+ and the lack of suitable cathode materials. Herein, a hydrated iron vanadate (Fe2V3O10.5∙1.5H2O, FOH) with a preferred orientation along the (200) plane is innovatively proposed and used as cathode material for ANIBs. The FOH cathode exhibits a remarkable capacity of 129.3 mAh g-1 at 50 mA g-1 and a super-high capacity retention of 95% at 500 mA g-1 after 700 cycles. The desirable Ni2+ storage capacity of FOH can be attributed to the preferentially oriented and tunnel structures, which offer abundant reaction active planes and a broad Ni2+ diffusion path, the abundant vacancies and high specific surface area further increase ion storage sites and accelerate ion diffusion in the FOH lattice. Furthermore, the Ni2+ storage mechanism and structural evolution in the FOH cathode are explored through ex situ XRD, ex situ Raman, ex situ XPS and other ex situ characteristics. This work opens a new way for designing novel cathode materials to promote the development of ANIBs.

2.
World J Gastrointest Surg ; 16(6): 1527-1536, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38983348

RESUMEN

BACKGROUND: Natural orifice specimen extraction surgery (NOSES) has emerged as a promising alternative compared to conventional laparoscopic-assisted total gastrectomy (LATG) for treating gastric cancer (GC). However, evidence regarding the efficacy and safety of NOSES for GC surgery is limited. This study aimed to compare the safety and feasibility, in addition to postoperative complications of NOSES and LATG. AIM: To discuss the postoperative effects of two different surgical methods in patients with GC. METHODS: Dual circular staplers were used in Roux-en-Y digestive tract reconstruction for transvaginal specimen extraction LATG, and its outcomes were compared with LATG in a cohort of 51 GC patients with tumor size ≤ 5 cm. The study was conducted from May 2018 to September 2020, and patients were categorized into the NOSES group (n = 22) and LATG group (n = 29). Perioperative parameters were compared and analyzed, including patient and tumor characteristics, postoperative outcomes, and anastomosis-related complications, postoperative hospital stay, the length of abdominal incision, difference in tumor type, postoperative complications, and postoperative survival. RESULTS: Postoperative exhaust time, operation duration, mean postoperative hospital stay, length of abdominal incision, number of specific staplers used, and Brief Illness Perception Questionnaire score were significant in both groups (P < 0.01). In the NOSES group, the postoperative time to first flatus, mean postoperative hospital stay, and length of abdominal incision were significantly shorter than those in the LATG group. Patients in the NOSES group had faster postoperative recovery, and achieved abdominal minimally invasive incision that met aesthetic requirements. There were no significant differences in gender, age, tumor type, postoperative complications, and postoperative survival between the two groups. CONCLUSION: The application of dual circular staplers in Roux-en-Y digestive tract reconstruction combined with NOSES gastrectomy is safe and convenient. This approach offers better short-term outcomes compared to LATG, while long-term survival rates are comparable to those of conventional laparoscopic surgery.

3.
Cell Regen ; 13(1): 12, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38861103

RESUMEN

Macrophages play crucial and versatile roles in regulating tissue repair and regeneration upon injury. However, due to their complex compositional heterogeneity and functional plasticity, deciphering the nature of different macrophage subpopulations and unraveling their dynamics and precise roles during the repair process have been challenging. With its distinct advantages, zebrafish (Danio rerio) has emerged as an invaluable model for studying macrophage development and functions, especially in tissue repair and regeneration, providing valuable insights into our understanding of macrophage biology in health and diseases. In this review, we present the current knowledge and challenges associated with the role of macrophages in tissue repair and regeneration, highlighting the significant contributions made by zebrafish studies. We discuss the unique advantages of the zebrafish model, including its genetic tools, imaging techniques, and regenerative capacities, which have greatly facilitated the investigation of macrophages in these processes. Additionally, we outline the potential of zebrafish research in addressing the remaining challenges and advancing our understanding of the intricate interplay between macrophages and tissue repair and regeneration.

4.
Phys Rev Lett ; 132(13): 133603, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38613308

RESUMEN

An integrated quantum light source is increasingly desirable in large-scale quantum information processing. Despite recent remarkable advances, a new material platform is constantly being explored for the fully on-chip integration of quantum light generation, active and passive manipulation, and detection. Here, for the first time, we demonstrate a gallium nitride (GaN) microring based quantum light generation in the telecom C-band, which has potential toward the monolithic integration of quantum light source. In our demonstration, the GaN microring has a free spectral range of 330 GHz and a near-zero anomalous dispersion region of over 100 nm. The generation of energy-time entangled photon pair is demonstrated with a typical raw two-photon interference visibility of 95.5±6.5%, which is further configured to generate a heralded single photon with a typical heralded second-order autocorrelation g_{H}^{(2)}(0) of 0.045±0.001. Our results pave the way for developing a chip-scale quantum photonic circuit.

5.
Opt Express ; 32(2): 2554-2560, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38297781

RESUMEN

We investigate the robustness of a modified multi-trench fiber (MTF) design with two gaps numerically. The excellent suppression of high-order modes is demonstrated over a wide range of the gap misalignment and the fundamental mode loss is barely affected even with the 5 dB/m scattering loss in gaps at the modified two-gap MTF for the first time. Therefore, the required fabrication accuracy decreases.

6.
J Phys Chem Lett ; 15(4): 1019-1027, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38253014

RESUMEN

Understanding the behavior of a polaron in contact with water is of significant importance for many photocatalytic applications. We investigated the influence of water on the localization and transport properties of polarons at the rutile (110) surface by constrained density functional theory. An excess electron at a dry surface favors the formation of a small polaron at the subsurface Ti site, with a preferred transport direction along the [001] axis. As the surface is covered by water, the preferred spatial localization of the polarons is moved from the subsurface to the surface. When the water coverage exceeds half a monolayer, the preferred direction of polaron hopping is changed to the [110] direction toward the surface. This characteristic behavior is related to the Ti3d-orbital occupations and crystal field splitting induced by different distorted structures under water coverage. Our work describes the reduced sites that might eventually play a role in photocatalysis for rutile (110) surfaces in a water environment.

7.
J Transl Med ; 22(1): 21, 2024 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-38178094

RESUMEN

BACKGROUND: Oral squamous cell carcinoma (OSCC), the predominant malignancy of the oral cavity, is characterized by high incidence and low survival rates. Emerging evidence suggests a link between circadian rhythm disruptions and cancer development. The circadian gene TIMELESS, known for its specific expression in various tumors, has not been extensively studied in the context of OSCC. This study aims to explore the influence of TIMELESS on OSCC, focusing on cell growth and metabolic alterations. METHODS: We analyzed TIMELESS expression in OSCC using western blot, immunohistochemistry, qRT-PCR, and data from The Cancer Genome Atlas (TCGA) and the Cancer Cell Line Encyclopedia (CCLE). The role of TIMELESS in OSCC was examined through clone formation, MTS, cell cycle, and EdU assays, alongside subcutaneous tumor growth experiments in nude mice. We also assessed the metabolic impact of TIMELESS by measuring glucose uptake, lactate production, oxygen consumption, and medium pH, and investigated its effect on key metabolic proteins including silent information regulator 1 (SIRT1), hexokinase 2 (HK2), pyruvate kinase isozyme type M2 (PKM2), recombinant lactate dehydrogenase A (LDHA) and glucose transporter-1 (GLUT1). RESULTS: Elevated TIMELESS expression in OSCC tissues and cell lines was observed, correlating with reduced patient survival. TIMELESS overexpression enhanced OSCC cell proliferation, increased glycolytic activity (glucose uptake and lactate production), and suppressed oxidative phosphorylation (evidenced by reduced oxygen consumption and altered pH levels). Conversely, TIMELESS knockdown inhibited these cellular and metabolic processes, an effect mirrored by manipulating SIRT1 levels. Additionally, SIRT1 was positively associated with TIMELESS expression. The expression of SIRT1, HK2, PKM2, LDHA and GLUT1 increased with the overexpression of TIMELESS levels and decreased with the knockdown of TIMELESS. CONCLUSION: TIMELESS exacerbates OSCC progression by modulating cellular proliferation and metabolic pathways, specifically by enhancing glycolysis and reducing oxidative phosphorylation, largely mediated through the SIRT1 pathway. This highlights TIMELESS as a potential target for OSCC therapeutic strategies.


Asunto(s)
Péptidos y Proteínas de Señalización del Ritmo Circadiano , Glucosa , Neoplasias de la Boca , Carcinoma de Células Escamosas de Cabeza y Cuello , Animales , Humanos , Ratones , Línea Celular Tumoral , Proliferación Celular/genética , Glucosa/metabolismo , Transportador de Glucosa de Tipo 1 , Lactatos , Ratones Desnudos , Neoplasias de la Boca/genética , Neoplasias de la Boca/patología , Sirtuina 1/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Péptidos y Proteínas de Señalización del Ritmo Circadiano/genética
8.
J Psychiatr Res ; 169: 126-133, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38016394

RESUMEN

Individuals with opioid use disorder (OUD) have been reported to show abnormal brain metabolism and impaired coupling among brain networks such as the default mode network (DMN), salience network (SN), and executive control network (ECN). However, the characteristics of brain glucose metabolism and its related functions in the brain networks in individuals with OUD remain unknown. Thirty-six individuals with OUD and thirty matched healthy controls (HCs) were recruited in this integrated positron emission tomography/magnetic resonance imaging (PET/MRI) study. Differences in glucose metabolism were analyzed by using 18F-fluorodeoxyglucose (18F-FDG), and the corresponding coupling characteristics of the individuals with OUD were also analyzed. The individuals with OUD showed widespread bilateral hypometabolism in the middle temporal gyrus (MTG), superior temporal gyrus, angular gyrus, supramarginal gyrus, inferior parietal lobe, Rolandic operculum, and left insula, but obvious hypermetabolism in the brainstem and left cerebellum. Meanwhile, in individuals with OUD, the hypometabolism of right MTG which is included in the DMN was accompanied by decreased coupling with the left superior frontal gyrus and right superior parietal gyrus which are included in the ECN. Furthermore, individuals with OUD showed a positive correlation between the duration of heroin use and glucose metabolism of the left MTG. The individuals with OUD were characterized by widespread bilateral hypometabolism in the temporal and parietal regions but obvious hypermetabolism in the brainstem and left cerebellum. The results suggest that the hypometabolism in the temporal and parietal regions might be related to DMN dysfunction and the hypermetabolism in the brainstem and left cerebellum may be compensate for other brain regions showing hypometabolism. In particular, hypometabolism in the self-referential-related DMN regions in OUD might attenuate their relationships with the inhibitory-control-related ECN regions. These findings highlight the importance of evaluating the metabolic and functional profiles of the right MTG in future studies on the treatment of OUD.


Asunto(s)
Imagen por Resonancia Magnética , Trastornos Relacionados con Opioides , Humanos , Encéfalo/metabolismo , Tomografía de Emisión de Positrones , Glucosa/metabolismo , Trastornos Relacionados con Opioides/diagnóstico por imagen
9.
J Psychiatry Neurosci ; 48(4): E295-E304, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37437921

RESUMEN

BACKGROUND: Increasing evidence suggests that heroin addiction may be related to the dysfunction among the triple brain network (default mode network [DMN], salience network [SN] and executive control network [ECN]). However, the characteristics of glucose metabolism and metabolic connectivity among core regions of the triple brain network remain unknown. Therefore, we hypothesized that individuals with heroin dependence would show abnormal glucose metabolism and accompanied abnormal metabolic connectivity within the triple brain network. METHODS: Individuals with heroin dependence and healthy controls matched for age and sex underwent integrated positron emission tomography/magnetic resonance imaging (PET/MRI). Differences in glucose metabolism and metabolic connectivity among the DMN, SN and ECN were analyzed based on 18F-fluorodeoxyglucose PET and resting-state fMRI data. RESULTS: We included 36 individuals with heroin dependence and 30 matched healthy controls in our study. The heroin dependence group showed a significant reduction of glucose metabolism in the bilateral anterior insula (AI) and inferior parietal lobule (IPL), and a significantly decreased metabolic connectivity between the right AI and the left dorsolateral prefrontal cortex (DLPFC). The daily dose of methadone was negatively correlated with glucose metabolism of the right AI and right IPL. LIMITATIONS: The results revealed the glucose metabolism alterations and metabolic connectivity only within the triple brain network in individuals with heroin dependence; additional brain networks should be investigated in future studies. Although methadone is an opioid with a similar neurophysiological mechanism as heroin, the specific chronic effects of methadone on cerebral metabolism and metabolic connectivity should also be investigated in future studies. CONCLUSION: Our findings suggest that long-term opioid use might, to some extent, be associated with reduced synergistic ability between the SN and ECN, which may be associated with the dysfunction of cognitive control. In particular, the right AI, which showed hypometabolism and related reduction in SN-ECN metabolic connectivity, should receive increasing attention in future studies.


Asunto(s)
Dependencia de Heroína , Imagen por Resonancia Magnética , Humanos , Dependencia de Heroína/diagnóstico por imagen , Analgésicos Opioides , Glucosa , Metadona , Tomografía de Emisión de Positrones
10.
Cell Rep ; 42(7): 112793, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37453064

RESUMEN

Tissue-resident macrophages (TRMs) and dendritic cells (DCs) are highly heterogeneous and essential for immunity, tissue regeneration, and homeostasis maintenance. Here, we comprehensively profile the heterogeneity of TRMs and DCs across adult zebrafish organs via single-cell RNA sequencing. We identify two macrophage subsets: pro-inflammatory macrophages with potent phagocytosis signatures and pro-remodeling macrophages with tissue regeneration signatures in barrier tissues, liver, and heart. In parallel, one conventional dendritic cell (cDC) population with prominent antigen presentation capacity and plasmacytoid dendritic cells (pDCs) featured by anti-virus properties are also observed in these organs. Remarkably, in addition to a single macrophage/microglia population with potent phagocytosis capacity, a pDC population and two distinct cDC populations are identified in the brain. Finally, we generate specific reporter lines for in vivo tracking of macrophage and DC subsets. Our study depicts the landscape of TRMs and DCs and creates valuable tools for in-depth study of these cells in zebrafish.


Asunto(s)
Macrófagos , Pez Cebra , Animales , Macrófagos/metabolismo , Perfilación de la Expresión Génica , Células Dendríticas/metabolismo , Fagocitosis/genética , Transcriptoma/genética
11.
Clin Transl Med ; 13(7): e1321, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37400975

RESUMEN

BACKGROUND: Although ileal faecal diversion is commonly used in clinical settings, complications accompany it. Elucidating the intestinal changes caused by ileal faecal diversion will help resolve postoperative complications and elucidate the pathogenic mechanisms of associated intestinal disorders, such as Crohn's disease (CD). Therefore, our study aimed to provide new insights into the effects of ileal faecal diversion on the intestine and the potential mechanisms. METHODS: Single-cell RNA sequencing was performed on proximal functional and paired distal defunctioned intestinal mucosae from three patients with ileal faecal diversion. We also performed in vitro cellular and animal experiments, tissue staining and analysed public datasets to validate our findings. RESULTS: We found that the epithelium in the defunctioned intestine tended to be immature, with defective mechanical and mucous barriers. However, the innate immune barrier in the defunctioned intestine was enhanced. Focusing on the changes in goblet cells, we demonstrated that mechanical stimulation promotes the differentiation and maturation of goblet cells through the TRPA1-ERK pathway, indicating that the absence of mechanical stimulation may be the main cause of defects in the goblet cells of the defunctioned intestine. Furthermore, we found obvious fibrosis with a pro-fibrotic microenvironment in the defunctioned intestine and identified that monocytes may be important targets for faecal diversion to alleviate CD. CONCLUSIONS: This study revealed the different transcription landscapes of various cell subsets and the potential underlying mechanisms within the defunctioned intestine, when compared to the functional intestine, based on the background of ileal faecal diversion. These findings provide novel insights for understanding the physiological and pathological roles of the faecal stream in the intestine.


Asunto(s)
Enfermedad de Crohn , Ileostomía , Humanos , Ileostomía/efectos adversos , Enfermedad de Crohn/etiología , Enfermedad de Crohn/patología , Enfermedad de Crohn/cirugía , Heces , Complicaciones Posoperatorias/patología , Mucosa Intestinal/patología
12.
Chem Sci ; 14(23): 6289-6294, 2023 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-37325155

RESUMEN

Improving the sluggish kinetics of the hydrogen oxidation reaction (HOR) under alkaline electrolytes plays a significant role in the practical application of alkaline polymer electrolyte fuel cells (APEFCs). Here we report a sulphate functionalized Ru catalyst (Ru-SO4) that exhibits remarkable electrocatalytic performance and stability toward alkaline HOR, with a mass activity of 1182.2 mA mgPGM-1, which is four-times higher than that of the pristine Ru catalyst. Theoretical calculations and experimental studies including in situ electrochemical impedance spectroscopy and in situ Raman spectroscopy demonstrate that the charge redistribution on the interface of Ru through sulphate functionalization could lead to optimized adsorption energies of hydrogen and hydroxide, together with facilitated H2 transfer through the inter Helmholtz plane and precisely tailored interfacial water molecules, contributing to a decreased energy barrier of the water formation step and enhanced HOR performance under alkaline electrolytes.

13.
Eur Spine J ; 32(7): 2441-2447, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37217823

RESUMEN

OBJECTIVE: Neurogenic bladder (NGB) is a serious complication after spinal cord injury (SCI), a destructive neurological disease. This study focused on exploring the efficacy of the magnetic stimulation of sacral nerve roots combined with Tui-na in treating NGB after SCI. METHODS: One hundred patients with NGB after SCI were studied, and intermittent clean catheterization was performed with a water intake program, and patients were grouped into four groups by the random number table method: general treatment group, Tui-na group, magnetic stimulation group, and combined treatment group. A series of relevant factors (voiding diary, urodynamics, and quality of life scores) and clinical efficacy of patients in the four groups before and after treatment were observed. RESULTS: The magnetic stimulation of sacral nerve roots alone, Tui-na alone, and the combination of both were all effective in improving bladder function and quality of life in patients with NGB after SCI, including improvements in voiding frequency, single urine output, maximum urine output, residual urine output, bladder volume and quality of life scores in patients with NGB after SCI. The efficacy of the magnetic stimulation of sacral nerve roots combined with Tui-na was better than that of the magnetic stimulation of sacral nerve roots alone and the Tui-na alone. CONCLUSION: This research demonstrates that the magnetic stimulation of sacral nerve roots combined with Tui-na treatment could effectively improve the urinary system and the quality of life of patients with NGB after SCI, which is worthy of clinical promotion and application.


Asunto(s)
Traumatismos de la Médula Espinal , Vejiga Urinaria Neurogénica , Humanos , Vejiga Urinaria Neurogénica/etiología , Vejiga Urinaria Neurogénica/terapia , Vejiga Urinaria/inervación , Calidad de Vida , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/terapia , Raíces Nerviosas Espinales , Fenómenos Magnéticos
14.
Cell Rep ; 42(5): 112483, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37148242

RESUMEN

Metaphocytes are tissue-resident macrophage (TRM)/dendritic cell (DC)-like cells of non-hematopoietic origin in zebrafish barrier tissues. One remarkable property of metaphocytes is their ability to capture soluble antigens from the external environment via transepithelial protrusions, a unique function manifested by specialized subpopulations of the TRMs/DCs in mammal barrier tissues. Yet, how metaphocytes acquire myeloid-like cell properties from non-hematopoietic precursors and how they regulate barrier immunity remains unknown. Here, we show that metaphocytes are in situ generated from local progenitors guided by the ETS transcription factor Spic, the deficiency of which results in the absence of metaphocytes. We further document that metaphocytes are the major IL-22BP-producing cells, and the depletion of metaphocytes causes dysregulated barrier immunity that resembles the phenotype of IL-22BP-deficient mice. These findings reveal the ontogeny, development, and function of metaphocytes in zebrafish, which facilitates our understanding of the nature and function of the mammalian TRM/DC counterparts.


Asunto(s)
Células Dendríticas , Pez Cebra , Animales , Ratones , Diferenciación Celular , Proteínas de Unión al ADN , Mamíferos , Receptores de Interleucina/metabolismo
15.
Environ Sci Pollut Res Int ; 30(28): 72187-72206, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37166730

RESUMEN

Coalbed methane (CBM) is primarily stored and transported through the pores in the coal matrix, making it essential to study the development of different scales of pores in coal to better understand the evaluation and exploration of CBM. In this study, four coal samples of varying ranks (Ro,max = 0.68%-2.86%) were selected, and different scale pores were obtained through low-pressure CO2 and Ar adsorption (LP-CO2/ArGA) and mercury intrusion porosimetry (MIP) experiments. A full-scale pore evaluation model was established, and the impact of pores on methane adsorption and restriction was analyzed and discussed through high-pressure adsorption experiments. Our results show that (1) at high pressures (> 100 MPa), the MIP technique caused pore compression and overestimated the pore size below 30 nm by up to 47.2%; (2) to obtain a comprehensive pore evaluation, we developed an accurate model that combines LP-CO2/ArGA with NLDFT and BJH and NLDFT models to determine micropore (0.3-1.5 nm) and mesopore (1.5-30 nm) parameters. By combining this model with MIP test results, we can obtain a full-scale pore size in the range of 0.3 nm-200 µm; (3) coal rank affected the development of full-scale pore characteristics. As coal rank increased, the specific surface area (SSA) of micropores and adsorption capacity of methane first decreased, then increased. Micropores were found to be the most important storage space for CBM and control gas adsorption, with a microporous SSA and PV to total SSA and total PV ratio of 97.93% and 63.69%, respectively. (4) We also observed a significant linear relationship between the fractal dimension of micropores and the Langmuir volume (VL) based on fractal theory. As the fractal dimension increased, VL also increased (R2 = 0.8581), indicating that VL is controlled by the complexity of micropores, which is consistent with the comprehensive evaluation index (Dt) and VL (R2 = 0.8744). Based on our predicted model, VL can be estimated using the SSA of micropores and Dt. Our findings shed light on the relationship between pore morphology and CBM occurrence and have practical implications for fields such as catalytic synthesis, E-CBM, and gas purification.


Asunto(s)
Dióxido de Carbono , Mercurio , Adsorción , Transporte Biológico , Carbón Mineral , Metano
16.
Clin Exp Med ; 23(7): 2941-2951, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37016064

RESUMEN

Metformin is among the most widely used antidiabetic drugs. Studies over the past few years have identified multiple novel molecular targets and pathways that metformin acts on to exert its beneficial effects in treating type 2 diabetes as well as other disorders involving dysregulated inflammation and redox homeostasis. In this mini-review, we discuss the latest cutting-edge research discoveries on novel molecular targets of metformin in glycemic control, cardiovascular protection, cancer intervention, anti-inflammation, antiaging, and weight control. Identification of these novel targets and pathways not only deepens our understanding of the molecular mechanisms by which metformin exerts diverse beneficial biological effects, but also provides opportunities for developing new mechanistically based drugs for human diseases.


Asunto(s)
Diabetes Mellitus Tipo 2 , Metformina , Humanos , Metformina/farmacología , Metformina/uso terapéutico , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Hipoglucemiantes/farmacología , Hipoglucemiantes/uso terapéutico
17.
ACS Omega ; 8(10): 9526-9538, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36936307

RESUMEN

In China, the capacity to produce coalbed methane and extract underground gas is restricted by the prevalence of low-permeability coal seams. Liquid nitrogen fracturing is a new low temperature-high-pressure anhydrous fracturing technology that uses low temperature and high frost heave forces to increase coal permeability. To better understand the liquid nitrogen fracturing effect on coal, we conduct the liquid nitrogen freeze-thaw cycle (LNCFT) experiments on different rank coals from Qinghai, Shanxi, and Shaanxi provinces. We combined the low-pressure nitrogen and carbon dioxide adsorption experiment with the non-local density functional theory model and mercury injection porosimetry with compressibility corrections to examine the full pore size distributions of untreated and water-saturated samples before and after LNCFT. The results found that LNCFT can effectively increase the pore volume (PV) and specific surface area of the water-saturated coal sample. Compared with the raw coal, the increased ratio of the full pore size PV is 70.41-100.17%. However, the scale-selective transformation effect on pores during liquid nitrogen fracturing is noticeable. Under the same conditions, LNCFT can significantly increase the pore volume of micropores (>2 nm) and macropores (>50 nm), and the increase ratios are 24.40-44.16 and 103.55-327.93%, respectively. The PV of mesopores (2-50 nm) shows a slightly increasing trend with the increase in metamorphic degree, and the increase ratio is between 8.7 and 56%. Comparing the full pore size distribution curves before and after LNCFT, it is found that the alteration of high-volatile bituminous coal (BLT coal) and anthracite (SH coal) has more significance in the range of less than 2 and 50-20,000 nm, while middle-volatile bituminous coal (YJL coal) varies between 50 and 2000 nm. Meanwhile, the ratio of micropore and mesopore PV to the total decreased gradually before and after LNCFT, while the proportion of macropores increased, indicating that small-scale pores would intersect and connect to form larger-scale pores during the fracturing. The combined effects of temperature gradient, water-ice phase transition, and heat transmission rate are the key factors that determine the impact of LNCFT on pore size distribution. Our results provide new information for enhancing the permeability of low-permeability coal seams of different ranks.

18.
Opt Lett ; 48(6): 1367-1370, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36946929

RESUMEN

With the increasing signal rates of a long-haul backbone dense-wavelength-division-multiplexing (DWDM) transmission system, e.g., from 100 Gb/s to 400 Gb/s and even to 800 Gb/s, optical path impairments simultaneously become more severe. Harmful factors being formerly insignificant become noticeable, e.g., nonlinear phase noise (NPN) on main DWDM channels induced by the cross-phase modulation (XPM) from the low-speed optical supervisory channel (OSC). Field trials show that a greater than 5.13-dB penalty can be observed on the shortest channel of 400G DP-16QAM-PCS over G.654.E links, which greatly degrades the overall transmission performance and limits the maximum reach. In this paper, we propose a dual-OSC structure with opposite signals to compensate for performance degradation caused by OSC-induced NPN. This method involves no extra digital signal processing (DSP), which is not only simple but also applicable for universal signal rates. By experimental demonstration, a 1.32-dB gain in Q (dB) for 200G DP-16QAM transmission over 1618-km G.652.D can be done, almost achieving the same performance as the no OSC case.

20.
Sci Rep ; 13(1): 1226, 2023 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-36681731

RESUMEN

The exploration and development of the dual-provenance lower assemblage of the Yanchang Formation in the Jiyuan area has progressed rapidly. At the intersection of this bidirectional provenance system, a complex and variable spatial combination of sand bodies formed, resulting in significant structural heterogeneity in the development and distribution of reservoirs. Based on previous studies, this paper combines core data and logging data with a large number of analytical tests and production performance data to carry out research on the Chang 82-Chang 9 reservoir group in the lower assemblage of the Yanchang Formation in the Shijiawan-Buziwan area. Based on the analysis of sedimentary conditions, the sand body development pattern at the intersection of the bidirectional sedimentary system in the study area was analysed by stepwise dissection of the sand body architecture. After the types and characteristics of the 4th- to 5th-level architectural elements were determined, the spatial distribution of the combinations of these elements was assessed and combined with logging discriminant analysis and geometric shape prediction methods to identify a 'prism' architectural distribution pattern. The architectural elements are connected with the distribution of diagenetic facies, the spatial distribution patterns of different types of diagenetic facies under the constraints of the architecture are summarized by region, and the locations of potential favourable reservoir development are discussed. The results show that the degree of superposition and combination of the eight skeletal architectural elements in the target layers gradually deteriorate from the bottom to the top. In addition, the development scale and degree of architectural elements in the braided river delta system in the west are better than those in the meandering river delta system in the east. In the different sedimentary areas, the spatial combination styles of the architectural elements are quite different, and the combination of these elements gradually changes from a combination of braided channels (FA1) and abandoned channels (FA2) to a combination of underwater distributary channels (FA4). Matching of the distribution of diagenetic facies with the distribution of architectural elements reveals that the diagenetic facies dominated by intergranular pores and dissolution pores (associated with good reservoir physical properties) are usually found at the bottom or in the lower to middle parts of the skeletal architectural elements.


Asunto(s)
Sedimentos Geológicos , Arena , Humanos , Sedimentos Geológicos/química , Facies , Ríos/química
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