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INTRODUCTION: This study introduces and compares a new intraperitoneal laparoscopic para-aortic lymphadenectomy method to reach the level of the renal vein, the "tent-pitching" antegrade approach with the retrograde approach in gynecological malignancy surgeries in terms of success rate, complication incidence, and the number of lymph nodes removed. It focuses on the feasibility, safety, and effectiveness. Meanwhile, this article reports on the vascular anatomical variations discovered in the para-aortic region to enhance surgical safety. MATERIAL AND METHODS: This was a retrospective cohort study including patients undergone laparoscopic para-aortic lymphadenectomy at a single center from January 2020 to December 2023 for high-risk endometrial and early-stage ovarian cancer. Patient charts were reviewed for mode of operation, perioperative complications, operative details, and histopathology. The patients were divided into anterograde group and retrograde group according to the operation mode. The two groups were further compared based on the success rate of lymph node clearance at the renal vein level, perioperative complications, and the number of removed lymph nodes. Quantitative data were analyzed using the t-test, non-normally distributed data using the rank-sum test, and categorical data using Fisher's exact test and the chi-square test, with statistical significance defined as P < 0.05. RESULTS: Among 173 patients, the antegrade group showed higher surgery success (97.5% vs 68.82%), more lymph nodes removed (median 14 vs 7), and less median blood loss. The operation time was shorter in the antegrade group. Postoperative complications like lymphocele and venous thrombosis were lower in the antegrade group. Vascular abnormalities were found in 28.9% of patients, with accessory lumbar vein routing anomaly and accessory renal arteries being most common. CONCLUSIONS: The antegrade approach is feasible, safe, and effective, improving surgical exposure, reducing difficulty without additional instruments or puncture sites, and minimizing organ damage risk. It is effective in achieving better access to the renal vein and removing more para-aortic lymph nodes than the retrograde method. Recognizing and carefully managing the diverse vascular abnormalities in the para-aortic area, including variations in renal arteries, veins, and the inferior vena cava, is essential to reduce intraoperative bleeding and the likelihood of converting to open surgery.
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Laparoscopia , Excisão de Linfonodo , Neoplasias Ovarianas , Humanos , Feminino , Excisão de Linfonodo/métodos , Estudos Retrospectivos , Laparoscopia/métodos , Pessoa de Meia-Idade , Neoplasias Ovarianas/cirurgia , Neoplasias Ovarianas/patologia , Neoplasias do Endométrio/cirurgia , Neoplasias do Endométrio/patologia , Veias Renais/anatomia & histologia , Veias Renais/cirurgia , Adulto , Idoso , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Linfonodos/irrigação sanguínea , Linfonodos/cirurgiaRESUMO
BACKGROUND: The contribution of cholinergic degeneration to gait disturbance in Parkinson's disease (PD) is increasingly recognized, yet its relationship with dopaminergic-resistant gait parameters has been poorly investigated. We investigated the association between comprehensive gait parameters and cholinergic nucleus degeneration in PD. METHODS: This cross-sectional study enrolled 84 PD patients and 69 controls. All subjects underwent brain structural magnetic resonance imaging to assess the gray matter density (GMD) and volume (GMV) of the cholinergic nuclei (Ch123/Ch4). Gait parameters under single-task (ST) and dual-task (DT) walking tests were acquired using sensor wearables in PD group. We compared cholinergic nucleus morphology and gait performance between groups and examined their association. RESULTS: PD patients exhibited significantly decreased GMD and GMV of the left Ch4 compared to controls after reaching HY stage > 2. Significant correlations were observed between multiple gait parameters and bilateral Ch123/Ch4. After multiple testing correction, the Ch123/Ch4 degeneration was significantly associated with shorter stride length, lower gait velocity, longer stance phase, smaller ankle toe-off and heel-strike angles under both ST and DT condition. For PD patients with HY stage 1-2, there were no significant degeneration of Ch123/4, and only right side Ch123/Ch4 were corrected with the gait parameters. However, as the disease progressed to HY stage > 2, bilateral Ch123/Ch4 nuclei showed correlations with gait performance, with more extensive significant correlations were observed in the right side. CONCLUSIONS: Our study demonstrated the progressive association between cholinergic nuclei degeneration and gait impairment across different stages of PD, and highlighting the potential lateralization of the cholinergic nuclei's impact on gait impairment. These findings offer insights for the design and implementation of future clinical trials investigating cholinergic treatments as a promising approach to address gait impairments in PD.
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Transtornos Neurológicos da Marcha , Imageamento por Ressonância Magnética , Doença de Parkinson , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/fisiopatologia , Doença de Parkinson/diagnóstico por imagem , Masculino , Feminino , Idoso , Estudos Transversais , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Pessoa de Meia-Idade , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Neurônios Colinérgicos/patologia , Núcleo Basal de Meynert/diagnóstico por imagemRESUMO
BACKGROUND: Sensor-based gait analysis provides a robust quantitative tool for assessing gait impairments and their associated factors in Parkinson's disease (PD). Anxiety is observed to interfere with gait clinically, but this has been poorly investigated. Our purpose is to utilize gait analysis to uncover the effect of anxiety on gait in patients with PD. METHODS: We enrolled 38 and 106 PD patients with and without anxiety, respectively. Gait parameters were quantitively examined and compared between two groups both in single-task (ST) and dual-task (DT) walking tests. Multiple linear regression was applied to evaluate whether anxiety independently contributed to gait impairments. RESULTS: During ST, PD patients with anxiety presented significantly shorter stride length, lower gait velocity, longer stride time and stance time, longer stance phase, smaller toe-off (TO) and heel-strike (HS) angles than those without anxiety. While under DT status, the differences were diminished. Multiple linear regression analysis demonstrated that anxiety was an independent factor to a serials of gait parameters, particularly ST-TO (B = -2.599, (-4.82, -0.38)), ST-HS (B = -2.532, (-4.71, -0.35)), ST-TO-CV (B = 4.627, (1.71, 7.64)), ST-HS-CV(B = 4.597, (1.66, 7.53)), ST stance phase (B = 1.4, (0.22, 2.58)), and DT stance phase (B = 1.749, (0.56, 2.94)). CONCLUSION: Our study discovered that anxiety has a significant impact on gait impairments in PD patients, especially exacerbating shuffling steps and prolonging stance phase. These findings highlight the importance of addressing anxiety in PD precision therapy to achieve better treatment outcomes.
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Ansiedade , Análise da Marcha , Transtornos Neurológicos da Marcha , Doença de Parkinson , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/psicologia , Doença de Parkinson/fisiopatologia , Masculino , Feminino , Ansiedade/etiologia , Ansiedade/diagnóstico , Idoso , Análise da Marcha/métodos , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Pessoa de Meia-Idade , Marcha/fisiologia , Fenômenos BiomecânicosRESUMO
Revealing the responses of abundant and rare aerobic denitrifying bacteria to dissolved organic matter (DOM) composition is essential for understanding the aquatic N cycle ecosystems. In this study, fluorescence region integration and high-throughput sequencing techniques were used to investigate the spatiotemporal characteristics and dynamic response of DOM and aerobic denitrifying bacteria. The DOM compositions were significantly different among the four seasons (P < 0.001) without spatial differences. Tryptophan-like substances (P2, 27.89-42.67%) and microbial metabolites (P4, 14.62-42.03%) were the dominant components, and DOM exhibited strong autogenous characteristics. Abundant (AT), moderate (MT), and rare taxa (RT) of aerobic denitrifying bacteria showed significant and spatiotemporal differences (P < 0.05). The responses of α-diversity and niche breadth of AT and RT to DOM differed. The DOM explanation proportion for aerobic denitrifying bacteria exhibited spatiotemporal differences based on redundancy analysis. Foliate-like substances (P3) had the highest interpretation rate of AT in spring and summer, while humic-like substances (P5) had the highest interpretation rate of RT in spring and winter. Network analysis showed that RT networks were more complex than AT networks. Pseudomonas was the main genus associated with DOM in AT on a temporal scale, and was more strongly correlated with tyrosine-like substances (P1), P2, and P5. Aeromonas was the main genus associated with DOM in AT on a spatial scale and was more strongly correlated with P1 and P5. Magnetospirillum was the main genus associated with DOM in RT on a spatiotemporal scale, which was more sensitive to P3 and P4. Special operational taxonomic units were transformed between AT and RT with seasonal changes, but not between the two regions. To summarize, our results revealed that bacteria with different abundances utilized DOM components differently, and provides new insight on the spatiotemporal response of DOM and aerobic denitrifying bacteria in aquatic ecosystems of biogeochemical significance.
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Matéria Orgânica Dissolvida , Lagos , Lagos/química , Ecossistema , Água , Bactérias , China , Substâncias Húmicas/análise , Espectrometria de Fluorescência/métodosRESUMO
Animals show vast numerical competence in tasks that require both ordinal and cardinal numerical representations, but few studies have addressed whether animals can identify the numerical middle in a sequence. Two rhesus monkeys (Macaca mulatta) learned to select the middle dot in a horizontal sequence of three dots on a touchscreen. When subsequently presented with longer sequences composed of 5, 7 or 9 items, monkeys transferred the middle rule. Accuracy decreased as the length of the sequence increased. In a second test, we presented monkeys with asymmetrical sequences composed of nine items, where the numerical and spatial middle were distinct and both monkeys selected the numerical middle over the spatial middle. Our results demonstrate that rhesus macaques can extract an abstract numerical rule to bisect a discrete set of items.
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Aprendizagem , Animais , Macaca mulattaRESUMO
BACKGROUND: Previous reports have described hypogonadism associated with virus infection such as hantavirus, human immunodeficiency virus (HIV) or severe acute respiratory syndrome coronavirus 2 (SARS-COV-2). However, to our best knowledge there has been no case report of secondary hypogonadism following hand, foot, and mouth disease (HFMD). CASE PRESENTATION: A previously healthy 28-year-old man with no history of major physical and psychological trauma, presented with bilateral gynecomastia and erectile dysfunction 2 weeks after HFMD. Laboratory testament showed the level of gonadotropin hormones declined. Imaging examination demonstrated no major abnormal change in pituitary or reproductive system. The diagnosis of hypogonadism was established. Then the patient was ordered to maintain mental health outward of hospital without drug intervention. One month after presentation, his gonadotropin hormone level and sexual desire had recovered, while bilateral gynecomastia and erectile dysfunction symptoms disappeared. CONCLUSIONS: Physicians should notice the possibility for hypogonadism in adult patients with a recent history of HFMD.
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COVID-19 , Disfunção Erétil , Doença de Mão, Pé e Boca , Hipogonadismo , Adulto , Disfunção Erétil/etiologia , Doença de Mão, Pé e Boca/complicações , Doença de Mão, Pé e Boca/diagnóstico , Humanos , Masculino , SARS-CoV-2RESUMO
Eimeria tenella is the most pathogenic and common coccidia that causes chicken coccidiosis. The intracellular free Ca2+ of the host cell is closely related to the invasion, development, and proliferation of intracellular parasites. To determine the dynamic changes of intracellular free Ca2+ and its function in the process of E. tenella invading host cells, we established a chick embryo cecal epithelial cells model of E. tenella infection. Chick embryo cecal epithelial cells were treated with different Ca2+ signal inhibitor, respectively, and then infected with E. tenella. The results showed that extracellular Ca2+, Ca2+ channels on the cell membrane, IP3R ion channels on the endoplasmic reticulum membrane, and RyR ion channels regulated the free Ca2+ in cecal epithelial cells. Through fluorescence labeling and invasion rate detection, we found that the intracellular Ca2+ did not change significantly during the invasion of E. tenella, but its stability was critical to the invasion of parasites.
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Coccidiose , Eimeria tenella , Doenças das Aves Domésticas , Animais , Ceco/parasitologia , Embrião de Galinha , Galinhas , Coccidiose/veterinária , Eimeria tenella/metabolismo , Doenças das Aves Domésticas/parasitologiaRESUMO
The world-wide spreading of coronavirus disease (COVID-19) has greatly shaken human society, thus effective and fast-speed methods of non-daily-life-disturbance sterilization have become extremely significant. In this work, by fully benefitting from high-quality AlN template (with threading dislocation density as low as ≈6×108 cm-2) as well as outstanding deep ultraviolet (UVC-less than 280 nm) light-emitting diodes (LEDs) structure design and epitaxy optimization, high power UVC LEDs and ultra-high-power sterilization irradiation source are achieved. Moreover, for the first time, a result in which a fast and complete elimination of SARS-CoV-2 (the virus causes COVID-19) within only 1 s is achieved by the nearly whole industry-chain-covered product. These results advance the promising potential in UVC-LED disinfection particularly in the shadow of COVID-19.
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Cathodoluminescence (CL) is used as a quantitative characterization technique to probe impurities at the metal-organic chemical vapor deposition (MOCVD) grown GaN-on-GaN homoepitaxial interfaces. CL intensity contrast shows a strong correlation with the interfacial impurity concentrations. Based on the analysis of recombination mechanisms of electron beam induced non-equilibrium carriers, an analytical model is proposed to quantitatively determine the impurity concentrations from CL intensity. The extracted interfacial impurity concentrations from the analytical model show a good agreement with the compensation levels obtained from capacitance-voltage measurement, signifying the potential of CL for probing the quantitative impurity levels in GaN-on-GaN structures. This approach can also be extended to be applied in other material systems.
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The development of a multipurpose integrated syringe-pump-based environmental-water analyzer ( iSEA) and its application for spectrophotometric determination of ammonium is presented. The iSEA consists of a mini-syringe pump equipped with a selection valve and laboratory-programmed software written by LabVIEW. The chemistry is based on a modified indophenol method using o-phenylphenol. The effect of reagent concentrations and sample temperatures was evaluated. This fully automated analyzer had a detection limit of 0.12 µM with sample throughput of 12 h-1. Relative standard deviations at different concentrations (0-20 µM) were 0.23-3.36% ( n = 3-11) and 1.0% ( n = 144, in 24 h of continuous measurement, â¼5 µM). Calibration curves were linear ( R2 = 0.9998) over the range of 0-20 and 0-70 µM for the detection at 700 and 600 nm, respectively. The iSEA was applied in continuous real-time monitoring of ammonium variations in a river for 24 h and 14 days. A total of 1802 samples were measured, and only 0.4% was outlier data (≥3 sigma residuals). Measurements of reference materials and different aqueous samples ( n = 26) showed no significant difference between results obtained by reference and present methods. The system is compact (18 cm × 22 cm × 24 cm), portable (4.8 kg), and robust (high-resolution real-time monitoring in harsh environments) and consumes a small amount of chemicals (20-30 µL/run) and sample/standards (2.9 mL/run).
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Compostos de Amônio/análise , Monitoramento Ambiental/instrumentação , Análise de Injeção de Fluxo/instrumentação , Água Doce/análise , Compostos de Bifenilo/química , Desenho de Equipamento , Indofenol/química , Limite de Detecção , Rios/química , SeringasRESUMO
BACKGROUND: Long non-coding RNA nuclear paraspeckle assembly transcript 1 (lncRNA NEAT1) was found to be closely related to the pathological changes in brain and nervous system. However, the role of NEAT1 and its potential mechanism in Parkinson's disease (PD) largely remain uncharacterized. METHODS: In this study, PD mouse model was established by intraperitoneal injection of MPTP. The numbers of TH + neurons, NEAT1 expression and the level of PINK1, LC3-II, LC3-I protein were assessed in PD mice. SH-SY5Y cells were treated with MPP+ as PD cell model. RNA pull-down assay was used to identify the interaction between NEAT1 and PINK1 in vitro. The endogenous expression of NEAT1 was modified by lentiviral vector carrying interference sequence for NEAT1 in vivo. RESULTS: The numbers of TH+ neurons significantly decreased in PD mice compared with the control. The expressions of NEAT1, PINK1 protein and LC3-II/LC3-I level were increased by MPTP in vitro and in vivo. Moreover, NEAT1 positively regulated the protein level of PINK1 through inhibition of PINK1 protein degradation. And NEAT1 mediated the effects of MPP+ on SH-SY5Y cells through stabilization of PINK1 protein. The results of in vivo experiments revealed that NEAT1 knockdown could effectively suppress MPTP-induced autophagy in vivo that alleviated dopaminergic neuronal injury. CONCLUSION: LncRNA NEAT1 promoted the MPTP-induced autophagy in PD through stabilization of PINK1 protein.
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Autofagia , Mesencéfalo/metabolismo , Neurônios/metabolismo , Transtornos Parkinsonianos/metabolismo , Proteínas Quinases/metabolismo , RNA Longo não Codificante/metabolismo , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Animais , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Estabilidade Enzimática/efeitos dos fármacos , Masculino , Mesencéfalo/patologia , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/patologia , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/patologiaRESUMO
It is a fact that surface electron accumulation layer with sheet electron density in the magnitude of ~1013 cm−2 on InN, either as-grown or Mg-doped, makes InN an excellent candidate for sensing application. In this paper, the response of hydrogen sensors based on Mg-doped InN films (InN:Mg) grown by molecular beam epitaxy has been investigated. The sensor exhibits a resistance variation ratio of 16.8% with response/recovery times of less than 2 min under exposure to 2000 ppm H2/air at 125 °C, which is 60% higher in the magnitude of response than the one based on the as-grown InN film. Hall-effect measurement shows that the InN:Mg with suitable Mg doping level exhibits larger sheet resistance, which accords with buried p-type conduction in the InN bulk. This work shows the advantage of InN:Mg and signifies its potential for sensing application.
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BACKGROUND: This study assesses the value of the video head impulse test (vHIT) for early diagnosis of vestibular neuritis (VN) among acute vertigo. METHODS: Thirty-three cases of vestibular neuritis (VN), 96 patients with other acute vertigo (AV), and 50 cases of normal controls used vHIT to quantitatively test a pair of horizontal vestibulo-ocular reflection (VOR) gains, two pairs of vertical VOR gains, and the corresponding three pairs of VOR gain asymmetry. The peculiarity of VOR gains in VN and the differences between VN and other AV, normal controls by vHIT, were collected and analyzed. RESULTS: There were statistically significant differences in the three pairs of VOR gains asymmetry between VN and other AV, and normal controls (P<0.01). The sensitivity was 87.9% and specificity was 94.3% in differentiating VN from normal and other acute vertigo by vHIT. CONCLUSIONS: This study shows vHIT has advantages in the diagnosis of VN in acute vertigo with good sensitivity and specificity and indicates a widespread clinical application.
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Teste do Impulso da Cabeça , Vertigem/etiologia , Neuronite Vestibular/diagnóstico , Adulto , Idoso , Diagnóstico Precoce , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reflexo Vestíbulo-Ocular/fisiologia , Sensibilidade e Especificidade , Neuronite Vestibular/complicações , Neuronite Vestibular/fisiopatologia , Gravação em Vídeo/métodosRESUMO
Objective: To assess the clinical application of video head impulse test (vHIT) for vestibular function in vestibular neuritis (VN) and benign paroxysmal positional vertigo (BPPV) patients. Methods: Thirty-three patients with VN and 43 patients with BPPV were enrolled from Sir Run Run Shaw Hospital and Ningbo Second Hospital from March 15 to September 10, 2015; and 50 healthy controls were also enrolled in the study. vHIT was used to quantitatively test the vestibulo-ocular reflex (VOR) gains of a pair of horizontal semicircular canals. VOR gains two pairs of vertical semicircular canals, and the corresponding asymmetrical value of three VOR gains. The saccades information was also recorded. Results: Compared with the healthy control group and BPPV patients, the affected horizontal and vertical VOR gains were declined and the corresponding asymmetries were increased in VN patients (all P<0.01). BPPV group also showed higher vertical VOR gain asymmetries compared with the healthy control group (all P<0.01), but no significant difference was observed in VOR gains and horizontal VOR gain asymmetry (all P>0.05). The sensibility of vHIT in diagnosis of VN was 87.9%. Among 33 VN patients, 22 were diagnosed with superior vestibular nerve dysfunction, 7 were found with inferior vestibular nerve dysfunction and 3 were with both dysfunction; and 1 case was not distinguished. Conclusion: Video head impulse test can quantitatively evaluate the vestibular dysfunction of VN and can help early diagnosis of VN, which may be widely used in clinic.
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Vertigem Posicional Paroxística Benigna/diagnóstico , Reflexo Vestíbulo-Ocular/fisiologia , Doenças Vestibulares/classificação , Doenças Vestibulares/diagnóstico , Nervo Vestibular/patologia , Neuronite Vestibular/classificação , Neuronite Vestibular/diagnóstico , Teste do Impulso da Cabeça , Humanos , Movimentos Sacádicos/fisiologia , Canais Semicirculares/inervação , Canais Semicirculares/fisiopatologia , Sensibilidade e EspecificidadeRESUMO
The retention of coal fines in propped fractures impedes the efficient flow of gas and water, leading to a substantial decrease in coal seam permeability and gas production efficiency. In this article, a coal fine plugging removal agent with good dispersion stability and powerful powder-carrying capacity was developed to study the coal fine plugging removal and permeability enhancement in the propped fracture. The results show that 0.8% SDS + 0.4% NaCl + 0.8% BS-12 was the most effective coal fine plugging removal agent compounding system. Increasing the injection rate of the plugging removal agent and performing recycles of intermittent unblocking when it was used as a plugging agent will effectively enhance the gas-liquid two-phase effective permeability of propped fractures and improve the release of retained coal fines. After three recycles of intermittent unblocking, the coal fine discharging rate can be increased to more than 90%, resulting in a 3.88 times increase of the gas-liquid two-phase permeability compared to that with the single unblocking cycle. This method has important practical significance and theoretical value for solving the problem of coal fine plugging in fractures and ensuring the stable and efficient discharge of coalbed gas-water-coal fines.
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T cell receptor (TCR) is a kind of surface marker that are specific to T cells. The TCR regulates T cell function and participates in the body's immunological response to prevent immune dysregulation and inflammatory reactions by identifying and binding exogenous antigens. Due to its brief intracellular segment, TCR requires intracellular molecules to assist with signaling. Among these, the CD3 molecule is one of the most important. The CD3 molecule involves in TCR structural stability as well as T cell activation signaling. A TCR-CD3 complex is created when TCR and CD3 form a non-covalent bond. Antigen recognition and T cell signaling are both facilitated by the TCR-CD3 complex. When a CD3 subunit is absent, a TCR-CD3 complex cannot form, and none of the subunits is transported to the cell surface. Thus, T cells cannot develop. Consequently, research on the physiological functions and potential pathogenicity of CD3 subunits can clarify the pathogenesis of immune system diseases and can offer fresh approaches to the treatment of it. In this review, the structure and function of the TCR-CD3 complex in the immune system was summarized, the pathogenicity of each CD3 subunit and therapeutic approaches to related diseases was explored and research directions for the development of new targeted drugs was provided.
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Complexo Receptor-CD3 de Antígeno de Linfócitos T , Humanos , Animais , Complexo Receptor-CD3 de Antígeno de Linfócitos T/imunologia , Complexo Receptor-CD3 de Antígeno de Linfócitos T/metabolismo , Complexo CD3/imunologia , Complexo CD3/metabolismo , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Sistema Imunitário/imunologia , Sistema Imunitário/metabolismo , Transdução de Sinais/fisiologia , Transdução de Sinais/imunologia , Doenças do Sistema Imunitário/imunologia , Doenças do Sistema Imunitário/metabolismoRESUMO
In sulphur-coal symbiotic coal seams, after the mining of sulphide iron ore, when the coal resources are mined, the mine water accumulated in the roadway mining area will have a certain impact on the stability of the surrounding rock of the coal seam roadway. Taking the floor sandstone of sulfur coal symbiotic coal seam as the research object, the roof fissure water with pH values of 7.48, 4.81 and 2.62 was used as the experimental solution. 10 experimental schemes were designed to measure the compressive strength of the samples under the action of AMD, and the hydrochemical analysis of AMD was conducted. The pore structures of the samples before and after the action of AMD were analyzed. Based on the hydrochemistry and pore structure, the deterioration mechanism of compressive strength of the coal seam floor sandstone under the action of AMD was explained. The results indicated that the compressive strength of the samples decreased with the increasing action time of AMD. The compressive strength decreased with the increment of the porosity. The concentration of H+ ion in AMD was relatively small. Na2O in albite dissolved and reacted with water, leading to an increase in the concentration of Na+ ion. Soluble substances such as MgCl2 and CaSO4 in the pore structure dissolved, leading to an increase in the concentration of Ca2+ and Mg2+ ions. The dissolution of soluble substances and the physical-chemical reactions between solutions and minerals were the essential causes of the continuous deterioration of the compressive strength of the coal seam floor sandstone. The results of this study can provide a theoretical basis for the deterioration of the mechanical properties of the peripheral rock in the roadway of the sulphur coal seam, and can also provide a certain engineering reference for the sulphur coal seam roadway.
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The key to the variation in permeability within coal reservoirs lies in the stress-induced deformation and desorption-induced deformation during the coalbed methane (CBM) production. The differences in sample scale and measurement methods between stress-induced deformation and desorption-induced deformation significantly affect the accuracy of permeability measurements. Therefore, in order to elucidate the relationship between stress-induced deformation and adsorption-induced deformation, as well as the influencing factors, and to assess the accuracy of permeability evolution prediction, this study conducted a series of parallel experiments, including compression deformation experiments under stress loading (stress-induced deformation), methane adsorption-induced deformation experiments (adsorption-induced deformation), µCT scanning, and overburden permeability measurements.The results of the study indicate that stress-induced deformation and adsorption-induced deformation are negatively correlated but exhibit a relatively weak correlation. Stress-induced deformation encompasses deformation of coal matrix, minerals, and fractures, whereas adsorption-induced deformation primarily reflects coal matrix deformation. While there is some overlap between the two, they are not entirely identical. The main influencing factor of stress-induced deformation is the mechanical strength of coal, with minerals in coal increasing the Young's modulus of coal reservoirs. Among them, minerals that are more dispersed and have smaller particles have a more significant impact on stress-induced deformation. The primary influencing factor of adsorption-induced deformation is the deformation capability of the coal matrix, with minerals and fractures having less significant effects. Permeability changes are controlled by fracture deformation, but stress-induced deformation measurements weakly reflect this aspect, leading to an inability to accurately predict the scale of the impact of effective stress changes on permeability during CBM production and CO2-ECBM processes. In contrast, adsorption-induced deformation relatively accurately reflects the deformation capability of the coal matrix and provides a more accurate prediction of permeability rebound under the condition of almost unchanged effective stress in the late stages of mining. Therefore, deformation parameters under stress loading are challenging to directly apply to the prediction of permeability evolution, while adsorption-induced deformation parameters can be effectively utilized.
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The current study (a) examined ethnic differences in mothers' and children's responses to children's performance in a challenging task, (b) tested the associations among children's desire for assistance, maternal control, and children's emotional responses to the challenge, and (c) explored whether these associations held across three ethnicities-Asian Americans (AA), Latinx Americans (LA), and European Americans (EA). Results showed that children's emotional arousal significantly increased and emotional valence became significantly less positive over the course of children experiencing repeated challenges in front of their mothers. In terms of ethnic differences, LA mothers exhibited more control than EA mothers, but LA children responded less negatively to the challenging task than EA children. AA dyads did not significantly differ from LA or EA dyads on any maternal or child responses. However, regardless of ethnicity, stronger child desire for assistance was associated with greater maternal control and greater maternal control was associated with less emotional arousal and more positive child emotional valence. These findings suggest that, in a challenging context, maternal control is likely experienced by children as guidance that mitigates decreases in positive emotion. Our work has implications for interventions to encourage more emotionally responsive parental involvement with children in late childhood and early adolescence. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
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Etnicidade , Relações Mãe-Filho , Criança , Feminino , Adolescente , Humanos , Relações Mãe-Filho/psicologia , Emoções , Mães/psicologia , PaisRESUMO
During the development of deep coalbed methane (CBM), the production of coal fines is common and suppresses the yield of CBM. This work takes the deep CBM wells in the Qinshui Basin as a case study, and the output, composition, morphology, and sources of coal fines were investigated through scanning electron microscopy, X-ray diffraction, proximate analysis, and particle size measurement including image analysis, laser diffraction, and dynamic light scattering. The results indicate that, in comparison with shallow CBM wells, deep wells produce a greater quantity of coal fines which are darker in color and have smaller particle sizes, with the majority being less than 10 µm. The coal fines exist predominantly as aggregates that contained the iron-bearing and clay minerals. Based on the Liddinger particle settling model, the water production volume required for the coal fines to return to the surface in the Wuxiang block was calculated to be 8.55 m3/d. This work can provide a scientific basis for the prevention and control of coal fines in deep CBM wells.