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1.
Ultrason Sonochem ; 106: 106881, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38653147

RESUMO

When organic matter, especially sodium oxalate (Na2C2O4), accumulates to a certain extent, it will seriously affect the alumina production process in the refinery and therefore urgently needs to be removed. This work attempts to illuminate the benefits of ultrasonic intensification of the crystallization process of Na2C2O4, taking the alumina refinery waste liquor, i.e., flat plate washing liquor, as a case study. The effects of different operating parameters (seed crystal addition amount, caustic soda concentration, reaction time, ultrasonic power) on the crystallization behavior and yield are discussed, and it is found that ultrasonic can increase the Na2C2O4 removal rate to 70.4%. The addition of ultrasonic promotes the morphological evolution of Na2C2O4 and is of great significance to the optimization of the components of the precipitated Na2C2O4. Specifically, the proportion of Na2C2O4 in the crystallized product reaches 64% with conventional conditions, while it reaches 77% with ultrasonic conditions. Therefore, ultrasonic can greatly reduce the alkali loss caused by the crystallization process of Na2C2O4 in flat plate washing liquor, which has great economic benefits.

2.
Diabetes Metab Syndr Obes ; 17: 1701-1713, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38633278

RESUMO

Purpose: People with hyperuricemia (HUA) are often related to metabolic disorders such as diabetes, metabolic syndrome (MetS), and obesity. However, the correlation between excretion of uric acid and these diseases is unclear. Our study aimed to explore the relationship between uric acid excretion and type 2 diabetes (T2D). Methods: A total of 228 HUA patients from Tianjin Medical University General Hospital from 2022 to 2023 were included in this study. We collected demographic, biochemical, and anthropometric data on each subject. Urine uric acid excretion (UUAE) was calculated enzymatically from a single urine collection that lasted 24 hours. And fractional excretion of uric acid (FEUA) was calculated from serum uric acid and creatinine and uric acid and creatinine. Binary logistic regression modeling assessed the association between uric acid excretion and T2D. Results: Of the 228 subjects, 13.4% had T2D and 48.7% had obesity. The obesity group had a lower FEUA (p<0.05) and a higher UUAE compared to the control group (p<0.05). And FEUA had a stronger correlation with the risk of T2D (p<0.001). Also, there was a negative association between BMI and FEUA and a positive link between BMI and UUAE in the outpatients. Conclusion: Increased FEUA levels were significantly associated with T2D in HUA patients. Therefore, routine calculating of FEUA is essential for proper diagnosis and appropriate treatment T2D of in HUA patients.

3.
ACS Omega ; 9(10): 12219-12227, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38497007

RESUMO

A mass transfer model to predict the transport processes of magnesium and lithium ions through porous media in salt lakes has been proposed, which is a combination of the extended Nernst-Planck equation and Donnan effect, accounting for ion diffusion, electromigration, and convection within membrane pores. First, the morphological structure, thickness, surface roughness, and hydrophilicity of the membrane were characterized as fixed parameters, indicating that the surface of the nanofiltration membrane is smooth with low roughness and strong hydrophilicity, resulting in a lower desalination rate but higher water flux. Subsequently, numerical calculations based on the model were conducted to establish a reasonable transport equation for predicting the concentration and retention rate of the main magnesium and lithium ions. When compared with the experimental results, a deviation of less than 5.5% is obtained, confirming the accuracy of the model in describing ion mass transfer. Finally, computational fluid dynamics techniques were employed to simulate the model equations in both the feed and permeate subdomains, demonstrating that the flow characteristics align with reality. Thus, the established transport model exhibits higher predictive accuracy for NF ion separation than one-dimensional models.

4.
NeuroRehabilitation ; 54(2): 213-225, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38427506

RESUMO

BACKGROUND: NF2-schwannomatosis (NF2) is an autosomal dominant disorder prone to hearing loss. Auditory brainstem implants (ABIs) offer a promising solution for hearing rehabilitation in NF2. OBJECTIVE: To synthesize existing literature on ABI implantation in NF2, focusing on audiological outcomes and ABI-related complications. METHODS: The systematic review followed PRISMA guidelines and was registered in the PROSPERO database (CRD42022362155). Relevant studies were identified by searching PubMed, EMBASE, CENTRAL, CMB, and CNKI from inception to August 2023. Data on environmental sound discrimination, open-set discrimination, closed-set discrimination, and ABI-related complications were extracted and subjected to meta-analysis. Publication bias was evaluated using funnel plots and Egger's test. RESULTS: Thirty-three studies were included. The pooled estimate was 58% (95% CI 49-66%) for environmental sound discrimination and 55% (95% CI 40-69%) for closed-set discrimination. Regarding open-set discrimination, the pooled estimates were 30% (95% CI 19-42%) for sound only, 46% (95% CI 37-54%) for lip-reading only, and 63% (95% CI 55-70%) for sound plus lip-reading. The pooled occurrence of ABI-related complications was 33% (95% CI 15-52%). CONCLUSION: This meta-analysis underscores the effectiveness and safety of ABIs in NF2, providing valuable insights for evidence-based decision-making and hearing rehabilitation strategies.


Assuntos
Implante Auditivo de Tronco Encefálico , Implantes Auditivos de Tronco Encefálico , Neurilemoma , Neurofibromatoses , Neurofibromatose 2 , Neoplasias Cutâneas , Humanos , Neurofibromatose 2/complicações , Neurofibromatose 2/cirurgia , Resultado do Tratamento , Audição , Estudos Retrospectivos
5.
Mol Genet Metab Rep ; 38: 101063, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38469092

RESUMO

Background: Hypoparathyroidism, sensorineural deafness, and renal dysplasia (HDR) syndrome (Barakat syndrome) is a rare autosomal dominant disorder caused by mutations in the gene encoding GATA3 on chromosome 10p14. Method: Informed consent was obtained from a 38-year-old female patient. 5 mL of venous blood was collected and sent for whole-exome sequencing. GATA3 constructs of both wild-type and mutant were transfected into HEK-293 T cells. Three-dimensional modeling, luciferase-reporter gene test, western blotting and cellular immunofluorescence were used to evaluate the effect of the mutation. Results: A novel frameshift mutation c. 677dup(p.Pro227AlafsTer77), named P227Afs, was found in GATA3. Three-dimensional modeling revealed that the mutation caused the loss of the dual zinc finger structures 1 and 2 (ZNF1 and ZNF2) of the synthesized protein. Expression of wild-type GATA3 produced a six-fold increase in luciferase activity when compared with pcDNA3.1 vector only (P < 0.001), whereas the P227Afs mutant showed no increase. The mutation significantly reduced the transcriptional activity of GATA3. Immunofluorescence and western blotting analyses demonstrated that the mutation changed the nuclear location of GATA3 and caused difficulty in nuclearization. Conclusion: A novel heterozygous frameshift mutation in GATA3 was identified and showed to result in difficult nuclearization, and a dominant-negative effect on the wild-type.

6.
Sci Rep ; 14(1): 5179, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38431737

RESUMO

This paper constructs a two-layer road data asset revenue allocation model based on a modified Shapley value approach. The first layer allocates revenue to three roles in the data value realization process: the original data collectors, the data processors, and the data product producers. It fully considers and appropriately adjusts the revenue allocation to each role based on data risk factors. The second layer determines the correction factors for different roles to distribute revenue among the participants within those roles. Finally, the revenue values of the participants within each role are synthesized to obtain a consolidated revenue distribution for each participant. Compared to the traditional Shapley value method, this model establishes a revenue allocation evaluation index system, uses entropy weighting and rough set theory to determine the weights, and adopts a fuzzy comprehensive evaluation and numerical analysis to assess the degree of contribution of participants. It fully accounts for differences in both the qualitative and quantitative contributions of participants, enabling a fairer and more reasonable distribution of revenues. This study provides new perspectives and methodologies for the benefit distribution mechanism in road data assets, which aid in promoting the market-based use of road data assets, and it serves as an important reference for the application of data assetization in the road transportation industry.

7.
Acta Neurochir (Wien) ; 166(1): 127, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38460009

RESUMO

OBJECTIVE: To investigate the visual outcomes and optimal timing for repeat surgery in cases of postoperative hematoma following transsphenoidal surgery for pituitary neuroendocrine tumors (PitNETs). METHODS: A retrospective study was conducted on 28 patients who developed evident postoperative hematoma out of a total of 9,010 patients. The hematomas were classified into three types based on their CT appearance. Type 1a - mild high density with no tension, Type 1b - thin-layer high density; Type 2a - solid high density with large empty cavities, Type 2b - solid high density with small empty cavities; Type 3 -solid high density with no cavity showing high tension. Patient data were collected for analysis. RESULTS: The study cohort comprised 10 female and 18 male patients, with a mean age of 51.5±11.9 years. Most patients presented with large adenomas (median diameter 36mm). Postoperative visual sight improved in 12 patients, remained stable in 11 patients, and worsened in 5 patients. Notably, no patients experienced worsened visual sight beyond twenty-four hours after the operation. Among the five patients with visual deterioration, four had CT type 3 hematoma (4/6, 66.7%), and one had CT type 2b hematoma (1/9, 11.1%). Patients in the type 3 CT group were significantly more prone to experience visual deterioration compared to those in the type 2 group (odds ratio [OR] 2.154 [95% CI 1.858-611.014], P=.027). Four patients underwent repeat surgery after visual deterioration, resulting in visual improvement following a prolonged recovery period. Postoperative hematoma had limited impact on pituitary dysfunction and hyponatremia. CONCLUSION: Our study reveals a significant association between postoperative hematoma CT types and visual deterioration. For patients with stable visual sight and type 1 or 2a hematoma, conservative strategies may be considered. Conversely, type 2b and 3 patients are at higher risk of visual deterioration, especially within the first 24 hours after the operation. Consequently, early reoperation before vision worsens may be a prudent approach to reduce risks and improve visual outcomes, particularly in type 3 patients.


Assuntos
Adenoma , Tumores Neuroendócrinos , Neoplasias Hipofisárias , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Reoperação , Estudos Retrospectivos , Tumores Neuroendócrinos/cirurgia , Neoplasias Hipofisárias/cirurgia , Neoplasias Hipofisárias/patologia , Adenoma/cirurgia , Adenoma/patologia , Hematoma/diagnóstico por imagem , Hematoma/etiologia , Hematoma/cirurgia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Resultado do Tratamento
8.
Nat Sci Sleep ; 16: 177-191, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38404482

RESUMO

Background: Obstructive sleep apnea (OSA) is a common chronic disease with various comorbidities. The cardiometabolic index (CMI) reflects visceral fat tissue distribution and function, assessing the risk of obesity-related conditions such as metabolic syndrome (MetS) and stroke, which are strongly connected to OSA. The relationship between CMI with OSA and OSA combined with MetS (OMS) remains unclear. This study aims to evaluate the screening value of CMI for OSA and OMS, compared to the lipid accumulation product (LAP). Methods: A total of 280 participants who underwent polysomnography were finally included, with the measurements of metabolic-related laboratory test results such as total cholesterol and triglyceride. Receiver operating curve (ROC) analysis and calculation of the area under the curve (AUC) were conducted to assess the screening potential of CMI, LAP, and the logistic regression models established based on them for OSA and OMS. The Youden index, sensitivity, and specificity were used to determine the optimal cutoff points. Results: ROC curve analysis revealed that the AUCs for CMI in screening OSA and OMS were 0.808 and 0.797, and the optimal cutoff values were 0.71 (sensitivity 0.797, specificity 0.776) and 0.89 (sensitivity 0.830, specificity 0.662), respectively, showing higher Youden index than LAP. The AUCs of screening models based on CMI for OSA and OMS were 0.887 and 0.824, respectively. Conclusion: CMI and LAP can effectively screen for OSA and OMS, while CMI has more practical cutoff values for identifying the diseased states. Screening models based on CMI demonstrate a high discriminatory ability for OSA and OMS, which needs verification in a large-scale population.

9.
Nutr Metab Cardiovasc Dis ; 34(4): 1021-1027, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38402000

RESUMO

BACKGROUND AND AIM: Previous experimental and observational studies showed that serum uric acid (SUA) was associated with deep venous thrombosis (DVT), but the causal relationship is unclear. This study aimed to explore the potential causal association between SUA and DVT. METHODS AND RESULTS: We designed a two-sample Mendelian randomization (MR) analysis by using summary-level data from large genome-wide association studies performed in European individuals. A total of 14 SUA-related single-nucleotide polymorphisms (SNPs) (P value < 5 × 10-8) were identified as instrumental variables. The inverse variance weighted method was used as the primary method to compute the odds ratios (ORs) and 95 % confidence intervals (95 % CIs) for per standard deviation increase in SUA. MR Egger, weighted median, weighted mode, and simple mode were also applied to test the robustness of the results. We found no significant causal effects of serum uric acid on deep venous thrombosis (odds ratio [OR]: 1.000, 95 % confidence interval [CI]: 0.998-1.002, p = 0.78) by using inverse variance weighted. MR analyses based on other methods showed similar results. CONCLUSIONS: There was no potential causal associations between higher genetically predicted SUA levels and increased risk of deep venous thrombosis. Further, MR studies with more valid SNPs and more DVT cases are needed. Validation of the findings is also recommended.


Assuntos
Estudo de Associação Genômica Ampla , Trombose Venosa , Humanos , Análise da Randomização Mendeliana , Ácido Úrico , Polimorfismo de Nucleotídeo Único , Trombose Venosa/diagnóstico , Trombose Venosa/epidemiologia , Trombose Venosa/genética
10.
J Neurophysiol ; 131(4): 598-606, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38380844

RESUMO

The transplantation of neonatal microglia suppresses neuroinflammation caused by traumatic brain injury (TBI). This research aimed to explore the optimal time point of neonatal microglia transplantation for the best effect on the improvement of long-term cognitive function and inflammatory response in mouse models. qPCR and immunoblotting showed that the level of Iba1 gradually increased to the highest on day 7 and then gradually declined in TBI mice. Furthermore, it was observed that the level of CD86 and TNF-α increased to the highest after 7 days and subsequently was maintained until day 21, whereas the level of CD206 and IL-10 increased to the highest after 24 h and subsequently decreased until day 21 by qPCR and enzyme-linked immunosorbent assay. Afterward, it was shown that the neonatal microglia transplantation within 1 h significantly attenuated anxiety-like behavior and improved cognitive impairments in TBI mice. Mechanism exploration showed that the neonatal microglia could significantly decrease the level of cleaved caspase-3, M1/M2 polarization, and inflammatory cytokine (TNF-α) while increasing the level of anti-inflammatory factor IL-10 in TBI mice after transplantation within 1 h. Here, our findings demonstrated that neonatal microglia transplantation within 1 h significantly attenuated anxiety-like behavior and cognitive impairments caused by TBI.NEW & NOTEWORTHY The study demonstrated that neonatal microglia transplantation within 1 h significantly inhibited the pathogenesis of traumatic brain injury (TBI) in mouse models through inhibition of M1 polarization and promotion of M2 polarization.


Assuntos
Lesões Encefálicas Traumáticas , Microglia , Camundongos , Animais , Interleucina-10/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Anti-Inflamatórios/farmacologia , Camundongos Endogâmicos C57BL
11.
Environ Sci Technol ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38323894

RESUMO

Catalyzed reduction processes have been recognized as important and supplementary technologies for water treatment, with the specific aims of resource recovery, enhancement of bio/chemical-treatability of persistent organic pollutants, and safe handling of oxygenate ions. Palladium (Pd) has been widely used as a catalyst/electrocatalyst in these reduction processes. However, due to the limited reserves and high cost of Pd, it is essential to gain a better understanding of the Pd-catalyzed decontamination process to design affordable and sustainable Pd catalysts. This review provides a systematic summary of recent advances in understanding Pd-catalyzed reductive decontamination processes and designing Pd-based nanocatalysts for the reductive treatment of water-borne pollutants, with special focus on the interactions and transformation mechanisms of pollutant molecules on Pd catalysts at the atomic scale. The discussion begins by examining the adsorption of pollutants onto Pd sites from a thermodynamic viewpoint. This is followed by an explanation of the molecular-level reaction mechanism, demonstrating how electron-donors participate in the reductive transformation of pollutants. Next, the influence of the Pd reactive site structure on catalytic performance is explored. Additionally, the process of Pd-catalyzed reduction in facilitating the oxidation of pollutants is briefly discussed. The longevity of Pd catalysts, a crucial factor in determining their practicality, is also examined. Finally, we argue for increased attention to mechanism study, as well as precise construction of Pd sites under batch synthesis conditions, and the use of Pd-based catalysts/electrocatalysts in the treatment of concentrated pollutants to facilitate resource recovery.

12.
Mol Biol Rep ; 51(1): 236, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38285214

RESUMO

BACKGROUND: Early brain injury (EBI) is the vital factor in determining the outcome of subarachnoid hemorrhage (SAH). Schizandrin A (Sch A), the bioactive ingredient extracted from Schisandra chinensis, has been proved to exert beneficial effects in multiple human diseases. However, the effect of Sch A on SAH remains unknown. The current study was designed to explored role and mechanism of Sch A in the pathophysiological process of EBI following SAH. METHOD: A total of 74 male C57BL/6 J mice were subjected to endovascular perforation to establish the SAH model. Different dosages of Sch A were administrated post-modeling. The post-modeling assessments included neurological test, brain water content, RT-PCR, immunofluorescence, Nissl staining. Oxygenated hemoglobin was introduced into microglia to establish a SAH model in vitro. RESULT: Sch A significantly alleviated SAH-induced brain edema and neurological impairment. Moreover, application of Sch A remarkably inhibited SAH-induced neuroinflammation, evidenced by the decreased microglial activation and downregulated TNF-α, IL-1ß and IL-6 and expression. Additionally, Sch A, both in vivo and in vitro, protected neurons against SAH-induced inflammatory injury. Mechanismly, administration of Sch A inhibited miR-155/NF-κB axis and attenuated neuroinflammation, as well as alleviating neuronal injury. CONCLUSION: Our data suggested that Sch A could attenuated EBI following SAH via modulating neuroinflammation. The anti-inflammatory effect was exerted, at least partly through the miR-155/NF-κB axis, which may shed light on a possible therapeutic target for SAH.


Assuntos
Lesões Encefálicas , Ciclo-Octanos , Lignanas , MicroRNAs , Compostos Policíclicos , Hemorragia Subaracnóidea , Camundongos , Humanos , Animais , Masculino , Camundongos Endogâmicos C57BL , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/tratamento farmacológico , NF-kappa B , Doenças Neuroinflamatórias , Lesões Encefálicas/tratamento farmacológico , MicroRNAs/genética
13.
Cancer Gene Ther ; 31(1): 94-107, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37949945

RESUMO

The replication-stress response is essential to ensure the faithful transmission of genetic information to daughter cells. Although several stress-resolution pathways have been identified to deal with replication stress, the precise regulatory mechanisms for replication fork stability are not fully understood. Our study identified Methyl-CpG Binding Domain 1 (MBD1) as essential for the maintaining genomic stability and protecting stalled replication forks in mammalian cells. Depletion of MBD1 increases DNA lesions and sensitivity to replication stress. Mechanistically, we found that loss of MBD1 leads to the dissociation of Poly(ADP-ribose) polymerase 1 (PARP1) from the replication fork, potentially accelerating fork progression and resulting in higher levels of transcription-replication conflicts (T-R conflicts). Using a proximity ligation assay combined with 5-ethynyl-2'-deoxyuridine, we revealed that the MBD1 and PARP1 proteins were recruited to stalled forks under hydroxyurea (HU) treatment. In addition, our study showed that the level of R-loops also increased in MBD1-delated cells. Without MBD1, stalled replication forks resulting from T-R conflicts were primarily degraded by the DNA2 nuclease. Our findings shed light on a new aspect of MBD1 in maintaining genome stability and providing insights into the mechanisms underlying replication stress response.


Assuntos
Dano ao DNA , Replicação do DNA , Humanos , Animais , Instabilidade Genômica , Mamíferos/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição , Poli(ADP-Ribose) Polimerase-1/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo
14.
J Clin Invest ; 134(1)2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37934606

RESUMO

Mutations in the BRCA2 tumor suppressor gene have been associated with an increased risk of developing prostate cancer. One of the paradoxes concerning BRCA2 is the fact that its inactivation affects genetic stability and is deleterious for cellular and organismal survival, while BRCA2-mutated cancer cells adapt to this detriment and malignantly proliferate. Therapeutic strategies for tumors arising from BRCA2 mutations may be discovered by understanding these adaptive mechanisms. In this study, we conducted forward genetic synthetic viability screenings in Caenorhabditis elegans brc-2 (Cebrc-2) mutants and found that Ceubxn-2 inactivation rescued the viability of Cebrc-2 mutants. Moreover, loss of NSFL1C, the mammalian ortholog of CeUBXN-2, suppressed the spindle assembly checkpoint (SAC) activation and promoted the survival of BRCA2-deficient cells. Mechanistically, NSFL1C recruited USP9X to inhibit the polyubiquitination of AURKB and reduce the removal of AURKB from the centromeres by VCP, which is essential for SAC activation. SAC inactivation is common in BRCA2-deficient prostate cancer patients, but PP2A inhibitors could reactivate the SAC and achieve BRCA2-deficient prostate tumor synthetic lethality. Our research reveals the survival adaptation mechanism of BRCA2-deficient prostate tumor cells and provides different angles for exploring synthetic lethal inhibitors in addition to targeting DNA damage repair pathways.


Assuntos
Neoplasias da Próstata , Mutações Sintéticas Letais , Animais , Humanos , Masculino , Proteína BRCA2 , Caenorhabditis elegans/genética , Pontos de Checagem da Fase M do Ciclo Celular/genética , Mamíferos/metabolismo , Mutação , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Ubiquitina Tiolesterase/genética , Proteína Fosfatase 2/metabolismo
16.
Environ Res ; 243: 117842, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38065384

RESUMO

The potential health risk caused by long-term exposure to heavy metals in household dust is not only depended on their total content, but also bioaccessibility. In this study, twenty-one dust samples were collected from residential buildings, schools, and laboratories in 14 provincial-capital/industrial cities of China, aiming to evaluate the total contents, fractionation, bioaccessibility and health risks of nine heavy metals (As, Cd, Cr, Ni, Pb, Mn, Zn, Fe, and Cu). Results showed that the highest levels of Cd, Cr, Ni and Zn were found in laboratory dust, As, Pb and Mn in school dust, and Fe and Cu in residential dust, indicating different source profiles of the heavy metals. The mean bioaccessibility of the heavy metals across all samples as evaluated using SBRC (Solubility Bioavailability Research Consortium), IVG (In Vitro Gastrointestinal), and PBET (Physiologically Based Extraction Test) assays was 58.4%, 32.4% and 17.2% in gastric phase (GP), and 24.9%, 21.9% and 9.39% in intestinal phase (IP), respectively. Cadmium had the highest content in the fractions of E1+C2 (43.7%), as determined by sequential extraction, and Pb, Mn, and Zn had a higher content in E1+C2+F3 (64.2%, 67.2%, 78.8%), resulting in a higher bioaccessibility of these heavy metals than others. Moreover, the bioaccessibility of most heavy metals was inversely related to dust pH (R = -0.18 in GP; -0.18 in IP; P < 0.01) and particle size, while a positive correlation was observed with total organic carbon (R = 0.40 in GP; 0.38 in IP; P < 0.01). The exposure risk calculated by the highest bioaccessibility was generally lower than that calculated by the total content. However, Pb in one school dust sample had an unacceptable carcinogenic risk (adult risk = 1.19 × 10-4; child risk = 1.08 × 10-4). This study suggests that bioaccessibility of heavy metals in household dust is likely related to geochemical fractions and physical/chemical properties. Further research is needed to explore the sources of bioaccessible heavy metals in household dust.


Assuntos
Metais Pesados , Poluentes do Solo , Criança , Adulto , Humanos , Poeira/análise , Cádmio , Cidades , Chumbo , Monitoramento Ambiental/métodos , Metais Pesados/análise , China , Medição de Risco/métodos , Poluentes do Solo/análise
17.
Ultrason Sonochem ; 101: 106684, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37979278

RESUMO

High content sulfur (S2-) in Bayer liquor can increase alkali consumption, accelerate equipment corrosion, especially seriously affect alumina production. The removal of S2- in Bayer liquor is studied using ultrasonic enhanced ozone method, which significantly improves the removal efficiency. Results indicate that the best removal efficiency of 93.83 % is obtained with reaction duration of 20 min, oxygen flow rate of 80 L/h, ultrasonic power of 60 W and reaction temperature of 60 °C. The comparative analysis shows that the removal efficiency of S2- is 25.34 % higher than that of ozone (O3) system after introducing ultrasound (US), indicating that US accelerates the mass transfer process of O3 and increases the hydroxyl radicals (OH) content. For further explanation of the mechanism of US/O3 system, EPR and XPS spectra are applied to analyze the content of free radical and the form of sulfur in Bayer liquor, indicating that the content of free radical in US/O3 system is more than US and O3 systems, and all sulfur is converted to SO42- after full oxidation.

18.
Sci Rep ; 13(1): 19261, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37935739

RESUMO

Bi-directional pedestrian flow in corridors is a complex dynamic system due to the diversity in pedestrian psychological characteristics. Incorporating individual differences of pedestrians is vital for improving pedestrian flow models. However, due to the inherent complexity and variability of pedestrian movement, model parameter calibration remains challenging. Controlled experiments are needed to collect empirical pedestrian movement data under different environments. This enriches the database on pedestrian movement patterns and provides necessary support for improving pedestrian flow models. To address this issue, we conducted controlled experiments to quantify pedestrian heterogeneity by defining the direction of fuzzy visual field (DFVF). The DFVF incorporates various static and dynamic pedestrian factors. We used it to modify the traditional cellular automata model. This improved model simulates bi-directional pedestrian movements in the corridors, reproduces density-speed and density-volume relationships, and reveals self-organization phenomena. Furthermore, an analysis was conducted to examine the impacts of pedestrian density and facility spatial layout on evacuation time. Pedestrian interactions were also studied to uncover fundamental bi-directional flow properties. As pedestrian density increased, the evacuation time showed an exponential upward trend. Corridor length significantly impacts evacuation time, while increasing corridor width helps control it. As crowd density increases, pedestrian flows exhibit three distinct steady states: the strolling flow at low densities, directional separated flows at medium densities, and dynamic multi-lane flows at high densities. In summary, the modified cellular automata model successfully incorporates pedestrian heterogeneity and reveals intrinsic bi-directional pedestrian flow patterns. This study provides valuable insights for pedestrian facility design and optimizing pedestrian flow organization.

19.
Nat Prod Res ; : 1-7, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37794774

RESUMO

A new tetrahydroimidazopyridine named butyl (5R,6R,7S,8S)-5,6,7,8-tetrahydro-6,7,8-trihydroxy-5-(hydroxymethyl)imidazo[1,2-a]pyridine-2-carboxylate(1), together with eight known compounds (2-9), were isolated from the fermentation broth of a marine-derived fungus Paraconiothyrium sp. YK-03. Their chemical structures were elucidated by extensive analysis of one-dimensional and two-dimensional NMR spectroscopy, HR-ESIMS and optical rotation. Among these compounds, compound 1 represented a rare tetrahydroimidazopyridine, and compounds 2-7 were isolated from the Paraconiothyrium species for the first time. A plausible biosynthetic pathway for compound 1 was proposed.

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