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1.
Sci Rep ; 14(1): 12605, 2024 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824246

RESUMEN

The diagnostic value of contrast-enhanced ultrasound combined with ultrasound elastography for benign and malignant thyroid nodules is still controversial, so we used meta-analysis to seek controversial answers. The PubMed, OVID, and CNKI databases were searched according to the inclusion and exclusion criteria. The literature was selected from the establishment of each database to February 2024. The QUADAS-2 tool assessed diagnostic test accuracy. SROC curves and Spearman's correlation coefficient were made by Review Manager 5.4 software to assess the presence of threshold effects in the literature. Meta-Disc1.4 software was used for Cochrane-Q and χ2 tests, which be used to evaluate heterogeneity, with P-values and I2 indicating heterogeneity levels. The appropriate effect model was selected based on the results of the heterogeneity test. Stata18.0 software was used to evaluate publication bias. The diagnostic accuracy of contrast-enhanced ultrasound combined with ultrasound elastography for benign and malignant thyroid nodules was evaluated by calculating the combined sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, DOR, and area under the SROC curve. A total of 31 studies included 3811 patients with 4718 nodules were analyzed. There is no heterogeneity caused by the threshold effect, but there is significant non-threshold heterogeneity. Combined diagnostic metrics were: sensitivity = 0.93, specificity = 0.91, DOR = 168.41, positive likelihood ratio = 10.60, and negative likelihood ratio = 0.07. The SROC curve area was 0.97. Contrast-enhanced ultrasound and elastography show high diagnostic accuracy for thyroid nodules, offering a solid foundation for early diagnosis and treatment.Trial registration. CRD42024509462.


Asunto(s)
Medios de Contraste , Diagnóstico por Imagen de Elasticidad , Nódulo Tiroideo , Ultrasonografía , Humanos , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/patología , Diagnóstico por Imagen de Elasticidad/métodos , Ultrasonografía/métodos , Diagnóstico Diferencial , Sensibilidad y Especificidad , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/diagnóstico
2.
World J Clin Cases ; 12(15): 2542-2550, 2024 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-38817218

RESUMEN

BACKGROUND: The number of patients undergoing solid organ transplantation has increased annually. However, infections in solid organ transplant recipients can have a severe effect on patient survival owing to the continued use of immunosuppressants. Carrimycin is a novel macrolide antibiotic produced by genetically engineered streptomyces spiramyceticus harboring a 4''-O-isovaleryltransferase gene (ist) from streptomyces thermotoleran. Carrimycin has good antibacterial and antiviral effects. However, no relevant studies have been conducted on the efficacy and safety of carrimycin in patients with severe pneumonia (SP) after solid organ transplantation. AIM: To explore the efficacy and safety of carrimycin in patients with SP after solid organ transplantation to provide a medication reference for clinical treatment. METHODS: In March 2022, ten patients with SP following solid-organ transplantation were treated at our hospital between January 2021 and March 2022. When the condition was critical and difficult to control with other drugs, carrimycin was administered. These ten patients' clinical features and treatment protocols were retrospectively analyzed, and the efficacy and safety of carrimycin for treating SP following solid organ transplantation were evaluated. RESULTS: All ten patients were included in the analysis. Regarding etiological agent detection, there were three cases of fungal pneumonia, two cases of bacterial pneumonia, two cases of Pneumocystis pneumonia, and three cases of mixed infections. After treatment with carrimycin, the disease in seven patients significantly improved, the course of the disease was significantly shortened, fever was quickly controlled, chest computed tomography was significantly improved, and oxygenation was significantly improved. Finally, the patients were discharged after curing. One patient died of acute respiratory distress syndrome, and two patients discontinued treatment. CONCLUSION: Carrimycin is a safe and effective treatment modality for SP following solid organ transplantation. Carrimycin may have antibacterial and antiviral effects in patients with SP following solid organ transplantation.

3.
Biosens Bioelectron ; 254: 116190, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38479340

RESUMEN

It is expected that waterless low-temperature stressful environments will induce stress responses in fish and affect their vitality. In this study, we developed a laser-activated, stretchable, highly conductive liquid metal (LM) based flexible sensor system for fish multi-scale bioimpedance detection. It has excellent conformability, electrical conductivity, bending and cyclic tensile stability. Meanwhile, test result showed that wireless power supply is a potential solution for realizing safe power supply for devices inside waterless low-temperature packages. In addition, a hierarchical regression model (GC-HRM) based on Granger causality was established. The result showed that tissue bioimpedance can induce changes in individual bioimpedance with unidirectional Granger causality. The R2 of the linear regression (LR), support vector regression (SVR) and artificial neural network (ANN) models under single-scale individual bioimpedance were 0.85, 0.90 and 0.78, respectively. By adding the multi-scale bioimpedance features, the R2 of the LR, SVR and ANN models were improved to 0.95, 1.00 and 0.98, respectively.


Asunto(s)
Técnicas Biosensibles , Animales , Redes Neurales de la Computación , Conductividad Eléctrica , Suministros de Energía Eléctrica , Peces , Aprendizaje Automático
4.
Small ; : e2400093, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38353062

RESUMEN

For large-size potassium accommodation, heterostructure usually suffers severe delamination and exfoliation at the interfaces due to different volume expansion of two-phase during charge/discharge process, resulting in the deconstruction of heterostructures and shortened lifespan of batteries. Here, an innovative strategy is proposed through constructing a microscopic heterostructure system containing copper quantum dots (Cu QDs) highly dispersed in the triphenyl-substituted triazine graphdiyne (TPTG) substrates (TPTG@CuQDs) to solve this problem. The copper quantum dots are uniformly anchored on TPTG substrates, generating a myriad of island-like heterogeneous structures, together with tandem toroidal built-in electric field (BIEF) between every micro heterointerface. The island-like heterostructure endows both benefits of exposed contact interface and robust architecture. Generated tandem toroidal BIEF provides efficient transport pathways with lower energy barriers, reducing the diffusion resistance and facilitating the reaction kinetics of potassium ions. When used as anode, the TPTG@CuQDs exhibit highly reversible capacity and low-capacity degradation (≈0.01% over 5560 cycles at 1 A g-1 ). Moreover, the TPTG@CuQDs-based full cell delivers an outstanding reversible capacity of ≈110 mAh g-1 over 800 cycles at 1 A g-1 . This quantum-scale heterointerface construction strategy offers a new approach toward stable heterostructure design for the application of metal ion batteries.

5.
J Nutr ; 154(4): 1262-1270, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38367806

RESUMEN

BACKGROUND: The relationship between whole grain intake and chronic kidney disease (CKD) remains uncertain. OBJECTIVE: This study aimed to evaluate the association between whole grain intake and risk of CKD in Chinese adults. METHODS: The present cross-sectional study used data from the China Health and Nutrition Survey conducted in 2009. Whole grain intake was measured using 3 consecutive 24-h dietary recalls and a household food inventory. A multivariable logistic regression model was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for risk of CKD. In addition, a restricted cubic spline was used to investigate the dose‒response relationship between whole grain and risk of CKD. RESULTS: A total of 6747 participants were included, 728 of whom had CKD. Compared with those in the lowest whole grain intake group, those in the higher grain intake group had an inverse association with risk of CKD (Q2: adjusted OR 0.70, 95% CI: 0.54, 0.89; Q3: adjusted OR 0.54, 95% CI: 0.42, 0.69; and Q4: adjusted OR 0.29, 95% CI: 0.21, 0.41). The association between whole grain intake and CKD seems to be stronger for individuals who were male (P for interaction = 0.008) or smokers (P for interaction = 0.013). In addition, the restricted cubic spline suggested an obvious L-shaped correlation. CONCLUSIONS: Increased whole grain intake was associated with a decreased risk of CKD in Chinese adults.


Asunto(s)
Insuficiencia Renal Crónica , Granos Enteros , Adulto , Humanos , Masculino , Femenino , Estudios Transversales , Insuficiencia Renal Crónica/epidemiología , Dieta , Encuestas Nutricionales
6.
Small ; 20(14): e2308905, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37988690

RESUMEN

A strategy of microcrystalline aggregation is proposed to fabricate energy storage electrode with outstanding capacity and stability. Carbon-rich electrode (BDTG) functionalized with benzo[1,2-b:4,5-b']dithiophene units and butadiyne segments are prepared. The linear conjugate chains pack as microcrystalline nanofibers on nanoscale, which further aggregates to form a porous interpenetrating network. The microcrystalline aggregation feature of BDTG exhibit stable structure during long cycling test, revealing the following advantage in structure and property. The stretchable butadiyne linker facilitates reversible adsorption and desorption of Li with the aid of adjacent sulfur heteroatom. The alkyne-alkene transition exhibits intrinsic structural stability of microcrystalline region in BDTG electrodes. Meanwhile, alkynyl groups and sulfur heteroatoms on the surface of BDTG nanofibers participate in the formation of microscopic interface, providing a stable interfacial contact between BDTG electrodes and adjacent electrolyte. As a proof-of-concept, BDTG-based electrode shows high capacity (1430 mAh g-1 at 50 mA g-1) and excellent cycle performance (8000 cycles under 5 A g-1) in half-cell of lithium-ion batteries, and a reversible capacity of 120 mAh g-1 is obtained under the current density of 2 C in full-cell. This work shows microcrystalline aggregation is beneficial to realize adaptive intrinsic structure and interface contact during the charge-discharge process.

7.
Chem Sci ; 14(20): 5266-5290, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37234883

RESUMEN

Two-dimensional (2D) materials are widely used as key components in the fields of energy conversion and storage, optoelectronics, catalysis, biomedicine, etc. To meet the practical needs, molecular structure design and aggregation process optimization have been systematically carried out. The intrinsic correlation between preparation methods and the characteristic properties is investigated. This review summarizes the recent research achievements of 2D materials in the aspect of molecular structure modification, aggregation regulation, characteristic properties, and device applications. The design strategies to fabricate functional 2D materials starting from precursor molecules are introduced in detail referring to organic synthetic chemistry and self-assembly technology. It provides important research ideas for the design and synthesis of related materials.

8.
Materials (Basel) ; 16(10)2023 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-37241338

RESUMEN

The objective of this work was to investigate the damage characteristics and failure modes of gypsum rock under dynamic impact loading. Split Hopkinson pressure bar (SHPB) tests were performed under different strain rates. The strain rate effects on the dynamic peak strength, dynamic elastic modulus, energy density, and crushing size of gypsum rock were analyzed. A numerical model of the SHPB was established using the finite element software, ANSYS 19.0, and its reliability was verified by comparing it to laboratory test results. The results showed that the dynamic peak strength and energy consumption density of gypsum rock increased exponentially with strain rate, and the crushing size decreased exponentially with the strain rate, both findings exhibited an obvious correlation. The dynamic elastic modulus was larger than the static elastic modulus, but did not show a significant correlation. Gypsum rock fracture can be divided into crack compaction, crack initiation, crack propagation, and breaking stages, and is dominated by splitting failure. With increasing strain rate, the interaction between cracks is noticeable, and the failure mode changes from splitting to crushing failure. These results provide theoretical support for improvements of the refinement process in gypsum mines.

9.
Sensors (Basel) ; 23(3)2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36772351

RESUMEN

The shell-closing strength (SCS) of oysters is the main parameter for physiological activities. The aim of this study was to evaluate the applicability of SCS as an indicator of live oyster health. This study developed a flexible pressure sensor system with polydimethylsiloxane (PDMS) as the substrate and reduced graphene oxide (rGO) as the sensitive layer to monitor SCS in live oysters (rGO-PDMS). In the experiment, oysters of superior, medium and inferior grades were selected as research objects, and the change characteristics of SCS were monitored at 4 °C and 25 °C. At the same time, the time series model was used to predict the survival rate of live oyster on the basis of changes in their SCS characteristics. The survival times of superior, medium and inferior oysters at 4 °C and 25 °C were 31/25/18 days and 12/10/7 days, respectively, and the best prediction accuracies for survival rate were 89.32%/82.17%/79.19%. The results indicate that SCS is a key physiological indicator of oyster survival. The dynamic monitoring of oyster vitality by means of flexible pressure sensors is an important means of improving oyster survival rate. Superior oysters have a higher survival rate in low-temperature environments, and our method can provide effective and reliable survival prediction and management for the oyster industry.


Asunto(s)
Ostreidae , Animales , Alimentos Marinos , Frío , Dimetilpolisiloxanos
10.
Chem Asian J ; 17(24): e202200901, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36239205

RESUMEN

Enhancing the electrochemical stability and reversibility of redox-active organic molecules is crucial to improve the performance of non-aqueous redox flow batteries (RFBs). Compared with the widely adopted strategy of molecular engineering, we show in this study that tuning the intermolecular interaction between the active material with the supporting electrolyte is another feasible way to address the performance of non-aqueous organic RFBs. Combined with theoretical and experimental investigations, the influence of Lewis acidity of the supporting electrolyte cations and anions on the electrochemical stability and reversibility of bipyridine-based anode material is revealed. As a demonstration, a redox flow cell based on 4,4'-bipyridine anolyte and ferrocene catholyte shows greatly enhanced performance by using supporting electrolyte composed of soft Lewis acid and soft Lewis base. This study provides an alternative, yet highly effective way to addressing the cyclability of an organic compound for non-aqueous RFBs.

11.
ACS Omega ; 7(38): 34296-34308, 2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-36188323

RESUMEN

Owing to differences in deformation characteristics of roadways with different section shapes and depths, it is difficult to determine the support form and grouting depth of a roadway, which can cause serious deformation to the roadway. To address the challenges in determining the shape and grouting depth of a roadway section when the mine depth is known, the loose zone range of the roadway was tested using the acoustic method, and the loose zone evolution law under different conditions was performed by numerical simulations. The research results revealed that when the ratio of the maximum principal stress to the minimum principal stress is η > 3, the distribution of the rock loosening zone under different cross-sectional shapes was roughly "butterfly-shaped", and the "smoother" the cross section in the design of the roadway, the smaller the range of the rock loosening zone. With the increase of burial depth, the rock loosening zone and sealing depth also increase; the rock loosening zone and burial depth have a power function relationship the rock loosening zone range = a·burial depth b ; the sealing depth and burial depth have a linear relationship R = aH + b.

12.
ACS Appl Mater Interfaces ; 14(37): 41834-41850, 2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36073504

RESUMEN

Combining photodynamic therapy (PDT) with natural killer (NK) cell-based immunotherapy has shown great potential against cancers, but the shedding of NK group 2, member D ligands (NKG2DLs) on tumor cells inhibited NK cell activation in the tumor microenvironment. Herein, we assembled microenvironment-/light-responsive bio-nanosystems (MLRNs) consisting of SB-3CT-containing ß-cyclodextrins (ß-CDs) and photosensitizer-loaded liposomes, in which SB-3CT was considered to remodel the tumor microenvironment. ß-CDs and liposomes were linked by metalloproteinase 2 (MMP-2) responsive peptides, enabling sequential release of SB-3CT and chlorin e6 triggered by the MMP-2-abundant tumor microenvironment and 660 nm laser irradiation, respectively. Released SB-3CT blocked tumor immune escape by antagonizing MMP-2 and promoting the NKG2D/NKG2DL pathway, while liposomes were taken up by tumor cells for PDT. MLRN-mediated photo-immunotherapy significantly induced melanoma cell cytotoxicity (83.31%), inhibited tumor growth (relative tumor proliferation rate: 1.13% of that of normal saline) in the xenografted tumor model, and enhanced tumor-infiltrating NK cell (148 times) and NKG2DL expression (9.55 and 16.52 times for MICA and ULBP-1, respectively), achieving a synergistic effect. This study not only provided a simple insight into the development of new nanomedicine for programed release of antitumor drugs and better integration of PDT and immunotherapy but also a novel modality for clinical NK cell-mediated immunotherapy against melanoma.


Asunto(s)
Antineoplásicos , Inhibidores Enzimáticos/farmacología , Melanoma , beta-Ciclodextrinas , Línea Celular Tumoral , Compuestos Heterocíclicos con 1 Anillo , Humanos , Inmunoterapia , Liposomas , Metaloproteinasa 2 de la Matriz , Melanoma/patología , Subfamilia K de Receptores Similares a Lectina de Células NK/metabolismo , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Solución Salina , Sulfonas , Triazenos , Microambiente Tumoral
13.
Front Chem ; 10: 939368, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35755261

RESUMEN

At present, various materials based on helical polymers are nanoparticle or microsphere, which is not ease of use in practical application. Accordingly, facile preparation hierarchically porous monolith based on helical polymer needs to be developed. Herein, hierarchically porous boronic acid group-functionalized monoliths that exhibited optical activity were fabricated with a facile method based on crosslinking and polymerization-induced phase separation (CPIPS). Chiral substituted acetylene and achiral substituted acetylene with a boronic acid group were used as monomers. By regulating the composition of the pre-polymerization solution, the permeability and macropore size of the porous structure could be controlled. The hierarchically porous structure and large surface area were confirmed by scanning electron microscopy and nitrogen gas adsorption/desorption isotherms. In particular, the boronic acid functional group that can interact with a cis-diol group was successfully introduced on the skeleton surface of the monoliths. Further, the main chain of the copolymer that constituted the monoliths exhibited a high cis content and tacticity, and the monoliths showed good optical activity. Thus, the present study established a facile method to synthesize hierarchically porous boronic acid group-functionalized monoliths with optical activity via CPIPS, and the monoliths showed potential in recognition, separation, and adsorption of compound with chirality and cis-diol groups.

14.
ACS Biomater Sci Eng ; 8(6): 2676-2683, 2022 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-35616239

RESUMEN

Metal oxide affinity chromatography (MOAC) is considered to be one of the most effective methods for phosphopeptide enrichment. However, most of the materials used in the method are powder; frequent centrifugation is necessitated during the enrichment process, and potential risks of loss of peptides and materials and clogging of the column employed for liquid chromatography-mass spectrometry (LC-MS) arise. Moreover, the reusability of these materials to achieve sustainability was hardly investigated. To overcome these limitations, herein, inorganic titanium dioxide (TiO2) was coated onto the skeletal surface of the organic cellulose monolith (CM) material with a coral-like structure via a sol-gel method. This produced an organic-inorganic hybrid TiO2-CM material, which contained a combination of organic and inorganic substances, making it mimic the mollusk shell in terms of composition. The prepared TiO2-CM material as monolith exhibited excellent mechanical strength and did not break during the enrichment process; thus, the tedious implementation of multiple centrifugation cycles was prevented, thereby streamlining the experimental procedure and avoiding the loss of peptides and materials. Moreover, a large amount of TiO2 was introduced onto the surface of the CM material, and thus, the resultant TiO2-CM material exhibited a large surface area. As a result, the fabricated TiO2-CM material was successfully applied to the enrichment of phosphopeptides obtained from the tryptic digests of a BSA/ß-casein (mass ratio, 500/1) mixture. The results were superior to those achieved for commercial TiO2 beads, confirming that TiO2-CM has excellent selectivity for phosphopeptides and reusability. Furthermore, 9287 unique phosphopeptides derived from the 2661 phosphoproteins were successfully identified from two milligrams of tryptic digests of Hela cell exosomes obtained through five independent replications after enriching using the TiO2-CM material. The results indicated that the material has good application prospects in the analysis of protein phosphorylation. Furthermore, TiO2-CM consists of green and cheap cellulose as the skeleton, and its synthesis process is environment-friendly, simple, and inexpensive.


Asunto(s)
Celulosa , Fosfopéptidos , Biomimética , Células HeLa , Humanos , Fosfopéptidos/análisis , Fosfopéptidos/química , Titanio
15.
Nanomaterials (Basel) ; 12(8)2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35458066

RESUMEN

Photodynamic therapy (PDT) is a promising tumor therapy and has been proven to be an effective, safe and minimally invasive technique. Hematoporphyrin monomethyl ether (HMME) mediated PDT has been used in clinical treatment of port wine stain (PWS) due to its single component, high yield of singlet oxygen and short light-sensitive period. However, as an amphiphilic photosensitizer, HMME is easy to aggregate due to the presence of a hydrophobic group, which undesirably reduced its generation of singlet oxygen and bioavailability. In this study, we synthesized the stable conjugate of Au@TiO2 core-shell nanostructure with HMME, and the influence of different factors on PTD efficiency were studied. The results showed that the nanostructure had higher PTD efficiency for KB cells than that of HMME. The irradiation wavelength, gold nanoparticle shape and the shell thickness are all important factors for KB cell PDT.

16.
Nanomaterials (Basel) ; 12(4)2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35214976

RESUMEN

Gold nanosphere (AuS) is a nanosized particle with inert, biocompatible, easily modified surface functionalization and adequate cell penetration ability. Photothermal, photochemical, and vapor effects of AuS could be activated by irradiating with nanosecond laser to cause cell death. Hence, AuS-mediated phototherapy irradiated with nanosecond laser is a promising and minimally-invasive treatment method for cancer therapy. However, various effects require different parameters to be activated. At present, few studies have reported on the influence of parameters of AuS inducing cell death under nanosecond laser irradiation. This makes it very challenging to optimize gold-nanoparticle-mediated specific or synergistic anti-cancer therapy. In this study, we revealed the main parameters and threshold values for AuS-mediated gastric cancer phototherapy with nanosecond pulsed laser irradiation, evaluated the pathway of induced cell death, and discussed the roles of photothermal, photochemical and vapor effects which can induce the cell death. The results showed that AuS-mediated phototherapy activated with nanosecond pulsed laser is an effective method for gastric therapy, mainly based on the photochemical effect. Prolonging the incubation time could decrease the irradiation dose, increase ROS-mediated photothermal effect and vapor effect, and then quickly induce cell death to improve security.

17.
Int J Occup Med Environ Health ; 35(2): 199-208, 2022 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-34658367

RESUMEN

OBJECTIVES: The objective of this study was to explore the relationship between seat armrest height and human neck comfort when using a smartphone while sitting on a passenger seat during the flight. MATERIAL AND METHODS: The authors used a wireless angle-measuring instrument and subjective comfort scale to evaluate the changes of head flexion angle and neck comfort level of 24 young smartphone users in an aircraft simulated cabin. RESULTS: The study results indicated that using a smartphone while sitting on a passenger seat during the flight would pose a larger discomfort to the neck, and the discomfort would be higher for gaming than reading tasks. Seat armrest height is related to the comfort level of the neck when using a smartphone, increasing the height of the armrest can effectively alleviate discomfort in this state. CONCLUSIONS: Considering the prevalence of passengers using smartphones in aircraft, a seat armrest that can be properly adjusted in height, which can effectively reduce the risk of passenger head flexion angle and neck discomfort. Int J Occup Med Environ Health. 2022;35(2):199-208.


Asunto(s)
Postura , Teléfono Inteligente , Aeronaves , Diseño de Equipo , Ergonomía , Humanos , Cuello
18.
ACS Omega ; 6(50): 34920-34930, 2021 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-34963975

RESUMEN

Most coal mine field application processes are carried out using empirical formulas because of the insufficient understanding of the fracture development law of the static blasting technology. This lack of understanding results in poor coal seam gas extraction. In this study, a stress-damage coupling model was established to investigate the construction parameters of the static blasting technology using COMSOL simulation software. Then, a stress-damage-seepage coupling model was designed to study the evolution of the fracture field (seepage field) during the static blasting process using realistic failure process analysis simulation software. Finally, the influencing factors and fracturing effects were analyzed comprehensively. The research results show the following. (1) Comparing the simulation results with previous field tests reveals that the seepage law of the numerical simulation of the static blasting technology is consistent with the field test results, verifying the rationality of the stress-damage-seepage coupling model. (2) The development of coal seam fractures is affected by the expansion pressure, elastic modulus, and guide hole arrangement; the guide hole arrangement can play a role in guiding the development direction of fractures and enhancing the effect of fracturing. (3) The coal body mainly experienced the following five stages of fracturing: coal body compaction, microdamage formation, microfracture formation, large fracture formation, and fracture propagation. In addition, because of the rapid release of soundless cracking agents during the large fracture formation stage, the gas flow decreased in a short time. (4) The static blasting technology causes the coal seam permeability coefficient to increase. Compared with conventional extraction, the effective influence radius in the horizontal direction increases by 5.1 times, and the effective influence radius in the vertical direction increases by approximately 3 times. The static blasting technology can increase the number of coal seam fractures and significantly reduce the coal seam gas pressure, thereby enhancing coal seam permeability and realizing safe coal mining.

19.
Front Oncol ; 11: 803994, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34970499

RESUMEN

Acute leukemia during pregnancy (P-AL) is a rare disease with limited data regarding the management and outcomes of mothers and fetuses. We retrospectively analyzed the characteristics, pregnancy outcomes and maternal and neonatal prognoses of 52 patients with P-AL collected from January 2013 to December 2020 in our center. Seventeen (32.7%) patients received chemotherapy during pregnancy (exposed cohort), while 35 (67.3%) received chemotherapy after abortion/delivery (nonexposed cohort). Twenty-six (50.0%) pregnancies ended with abortion, and 26 (50.0%) babies were born through spontaneous delivery or cesarean section. Seven infants (26.9%) were born in the exposed cohort, while 19 infants (73.1%) were born in the nonexposed cohort. Fetuses in the exposed cohort had lower gestational ages (P=0.030) and birth weights (P=0.049). Considering the safety of the fetus, seven patients in the exposed cohort received low-dose chemotherapy, one patient received all-trans retinoic acid (ATRA) and one patient only received corticosteroids as induction therapy. Patients received low-dose chemotherapy as induction therapy had a lower complete remission (CR) rate (P=0.041), and more patients in this group received HSCT (P=0.010) than patients received intensive chemotherapy. Patients who delayed chemotherapy in the nonexposed cohort experienced a trend toward a higher mortality rate than patients who received timely chemotherapy (P=0.191). The CR (P = 0.488), OS (P=0.655), and DFS (P=0.453) were similar between the exposed and nonexposed cohorts. Overall, the 4-year overall survival (OS) and disease-free survival (DFS) rates were estimated at 49.1% and 57.8%, respectively. All newborns were living, without deformities, or developmental and intellectual disabilities. Our study indicated that P-AL patients in the first trimester might tend to receive chemotherapy after abortion. Both the status of disease and patients' willingness should be taken into consideration when clinicians were planning treatment strategies in the second or third trimester. Low-dose or delayed chemotherapy might decrease the efficacy of induction therapy and survival rate of patients, but HSCT could improve the prognosis.

20.
ACS Appl Mater Interfaces ; 13(40): 48020-48029, 2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34592813

RESUMEN

The present study reported the flexible and highly efficient one-step synthesis of chiral hierarchical porous monoliths via cross-linking and polymerization-induced phase separation using substituted acetylene and cross-linker in the presence of porogenic solvent (tetrahydrofuran and methanol) in which the complex doping and complicated procedures were not required. It was demonstrated that hierarchical pore structure with through-pore and high surface area existed in the monoliths, which provides more chiral sites and space for interaction between monolithic materials and the solution. The porous structures and pore size can be adjusted by changing the conditions of phase separation. Moreover, the prepared monoliths exhibited good optical activity, thermal stability and mechanical properties. Therefore, the hierarchically porous monoliths with optical activity were applied in enantioselective crystallization and showed good performance.

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