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1.
BMC Neurol ; 23(1): 278, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37488495

RESUMO

BACKGROUND: Low-grade gangliogliomas (GGs) are typically epileptogenic intracranial neoplasms. Yet, the presentation of simplex vertiginous experience and spontaneous downbeat nystagmus (DBN) has not been reported to date. CASE PRESENTATION: We present the case of a 26-year-old male with focal onset impaired awareness seizures, characterized by vertigo due to right temporal lobe epilepsy caused by ganglioglioma. As rare presentations, a spontaneous, consistent DBN in the absence of vertiginous experience was noticed. MRI suggested lesion in the right temporal pole. Twenty-four-hour continuous electroencephalogram (EEG) monitoring recorded periodic sharp and slow waves, originating from the right temporal lobe. The patient was completely relieved of the symptoms after surgical removal of the tumor, which was histologically confirmed as Grade I Ganglioglioma. CONCLUSIONS: Asides from the cortical pathogenesis of epileptic vertigo, this case also provides insight into the DBN secondary to tumor of the temporal lobe. Moreover, the 24-h EEG is advantageous to recognize vestibular seizures and localize the ictal onset areas.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Ganglioglioma , Nistagmo Patológico , Masculino , Humanos , Adulto , Ganglioglioma/diagnóstico , Ganglioglioma/diagnóstico por imagem , Convulsões/complicações , Epilepsia/complicações , Epilepsia do Lobo Temporal/complicações , Epilepsia do Lobo Temporal/diagnóstico por imagem , Eletroencefalografia , Imageamento por Ressonância Magnética , Vertigem/complicações , Nistagmo Patológico/etiologia
2.
Ear Hear ; 44(6): 1430-1436, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37171375

RESUMO

INTRODUCTION: Typewriter tinnitus refers to a special kind of staccato tinnitus, which is mostly described by patients as Morse code, popcorn, or machine-gun. It has been accepted that the mechanism of typewriter tinnitus is caused by the neurovascular compression of the cochleovestibular nerve. Patients who suffered from typewriter tinnitus have exhibited a good response to carbamazepine or oxcarbazepine, but there is a risk of recurrence after treatment cessation. The present study aims to determine the value of auditory brainstem response (ABR) in diagnosing typewriter tinnitus and predicting relapse after drug withdrawal. METHODS: Patients who presented with typewriter tinnitus from March 2019 to March 2022 were included for the present retrospective study. The auditory and vestibular test results and drug treatment effects were collected and analyzed. Patients with idiopathic unilateral subjective tinnitus, who were matched by age to patients with typewriter tinnitus at a ratio of 2:1, were consecutively recruited for the control group. RESULTS: Eighteen patients with typewriter tinnitus and 38 controls were included. Ears with typewriter tinnitus had longer interpeak latency (IPL) I-III, and wave III and V latencies, and a higher ratio of IPL I-III ≥2.3 ms based on ABR, when compared to the unaffected side and controls ( p <0.05). Seventeen patients with typewriter tinnitus responded positively to medication. Among these patients, seven patients had a relapse after drug cessation, while 10 patients did not have a relapse. The relapse group had significantly longer IPL I-III and wave V latency, older age, and poorer hearing, when compared to the nonrelapse group ( p < 0.05). Furthermore, IPL I-III had the largest area under the receiver operating characteristic curve, and the optimal cutoff was 2.4 ms (sensitivity, 100.0%; specificity, 66.7%). There were no significant differences in other demography or other clinical test results between the relapse and nonrelapse groups ( p > 0.05). Ramsay Hunt syndrome and neuromyelitis optica spectrum disorders were identified in two cases. CONCLUSION: Prolonged IPL I-III based on ABR can help in the diagnosis of typewriter tinnitus and its prognosis after treatment cessation. Patients with IPL I-III greater than 2.4 ms, older age and poorer hearing are more likely to relapse. In addition to the neurovascular conflict of the cochleovestibular nerve, the etiologies of neuroinflammation and demyelinating diseases are also possible for typewriter tinnitus.


Assuntos
Zumbido , Humanos , Zumbido/diagnóstico , Zumbido/etiologia , Estudos Retrospectivos , Prognóstico , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Recidiva
3.
Sensors (Basel) ; 23(13)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37447733

RESUMO

In the communication-based train control (CBTC) system, traditional modes such as LTE or WLAN in train-to-train (T2T) communication face the problem of a complex and costly deployment of base stations and ground core networks. Therefore, the multi-hop ad hoc network, which has the characteristics of being relatively flexible and cheap, is considered for CBTC. However, because of the high mobility of the train, it is likely to move out of the communication range of wayside nodes. Moreover, some wayside nodes are heavily congested, resulting in long packet queuing delays that cannot meet the transmission requirements. To solve these problems, in this paper, we investigate the next-hop relay selection problem in multi-hop ad hoc networks to minimize transmission time, enhance the network throughput, and ensure the channel quality. In addition, we propose a multiagent dueling deep Q learning (DQN) algorithm to optimize the delay and throughput of the entire link by selecting the next-hop relay node. The simulation results show that, compared with the existing routing algorithms, it has obvious improvement in the aspects of delay, throughput, and packet loss rate.


Assuntos
Redes de Comunicação de Computadores , Tecnologia sem Fio , Simulação por Computador , Comunicação , Algoritmos
4.
Nano Lett ; 22(22): 9084-9091, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36342419

RESUMO

Tribovoltaic direct-current (DC) nanogenerator made of dynamic semiconductor heterojunction is emerging as a promising mechanical energy harvesting technology. However, fundamental understanding of the mechano-electronic carrier excitation and transport at dynamic semiconductor interfaces remains to be investigated. Here, we demonstrated for the first time, that tribovoltaic DC effect can be tuned with metal-insulator transition (MIT). In a representative MIT material (vanadium dioxide, VO2), we found that the short-circuit current (ISC) can be enhanced by >20 times when the material is transformed from insulating to metallic state upon static or dynamic heating, while the open-circuit voltage (VOC) turns out to be unaffected. Such phenomenon may be understood by the Hubbard model for Mott insulator: orders' magnitude increase in conductivity is induced when the nearest hopping changes dramatically and overcomes the Coulomb repulsion, while the Coulomb repulsion giving rise to the quasi-particle excitation energy remains relatively stable.

5.
BMC Public Health ; 22(1): 1733, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096756

RESUMO

OBJECTIVE: Effect of physical exercise on pregnant women currently has become a hot topic in prenatal health care. In this study, A meta-analysis was conducted on account of Randomized Controlled Trial (RCT). It focused on evaluating the effect of physical exercise intervention on blood pressure so that could provide certain evidence for health care during pregnancy. METHODS: Results of relevant studies were retrieved from PubMed, Embase, Web of Science and the Cochrane Library, and all of these included studies were evaluated according to the Cochrane collaboration's tool for assessing the risk of bias. Stata 15.1 was used for meta-analysis, and mean difference (MD) was used as statistic for pooled analysis. The effect values were combined by conventional meta-analysis and Bayesian meta-analysis respectively, and the consistency of pooled results was considered as well. RESULTS: A total of 18 RCT studies were included in the quantitative analysis. The conventional meta-analysis showed differences in blood pressure between intervention group and control group (P < 0.05). Systolic and diastolic blood pressures of intervention group were 3.19 mmHg (95% CI: -5.13, -1.25) and 2.14 mmHg (95% CI: -4.26, -0.03) lower than that of control group, respectively. Bayesian meta-analysis showed that both systolic and diastolic pressure among intervention group decreased by 3.34 mmHg (95% CrI: -5.15, -1.56) and 2.14 mmHg (95% CrI: -3.79, - 0.50), respectively. Subgroup analysis supported that as long as healthy pregnant women participated in exercises, their blood pressure could be slightly regulated, while hypertension susceptible pregnant women significantly lowered blood pressure. CONCLUSION: Exercise intervention during pregnancy is beneficial to lower or normalize blood pressure, and this research provides clues for follow-up studies.


Assuntos
Exercício Físico , Hipertensão , Pressão Sanguínea/fisiologia , Exercício Físico/fisiologia , Terapia por Exercício/métodos , Feminino , Humanos , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Sístole
6.
Nano Lett ; 20(2): 1110-1116, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31891269

RESUMO

Light-weight ceramic aerogels hold promise for superinsulation. However, its mechanical instability and complex manufacturing hampered its technical applications. In this study, we demonstrate lightweight pore-gradient ceramic aerogel-like foam monoliths (PGAFoams) through one-pot and in situ bubble supported pore gradient formation. The mechanically strong PGAFoams exhibit a low thermal conductivity of 0.036 W m-1 K-1 and a compressive strength of 89.85 MPa. The pore gradient and integral ceramic monolith nature provides such hydrophobic PGAFoams with thermal management, robust soundproof, and fire-resistance performance. Highly machinable PGAFoams can be adapted into a variety of shapes and dimensions to accommodate complex geometry applications. The scalable manufacturing of lightweight PGAFoams opens up building insulation with remarkable thermal management, high mechanical strength, low mass density, superior soundproofing, and fire-retardant performances.

7.
Health Qual Life Outcomes ; 18(1): 218, 2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641044

RESUMO

BACKGROUND: The demand for assessing health-related quality of life (HRQoL) in chronic otitis media (COM) is increasing globally. The currently available Chinese-language patient-reported outcome measurement (PROM) specific for COM includes merely a limited range of related symptoms and dimensions. Hence, in this study, we aim to translate, culturally adapt, and validate the Zurich Chronic Middle Ear Inventory (ZCMEI-21) in Chinese, to enable a comprehensive evaluation of the patients' subjective health outcome in COM. METHODS: We sampled and surveyed 223 COM patients at three tertiary referral centers in China, using the Chinese translation of ZCMEI-21 (ZCMEI-21-Chn) and the EQ-5D questionnaire, a generic measure of HRQoL. Confirmatory factor analysis (CFA) was performed to investigate the structural model fit to the dataset. Cronbach's α and test-retest reliability coefficient were calculated to establish reliability, and correlation was tested between ZCMEI-Chn scores and EQ-5D scores for convergent validity. RESULTS: A total of 208 adult patients with COM were included, with a mean age of 46 years (SD 14 years) and a male proportion of 41% (85/208). A modified bifactor model with ωH of 0.65 and ECV of 0.47 was found to fit the scale scores, indicating fair general factor saturation and multidimensionality of the instrument. ZCMEI-21-Chn demonstrated good reliability (Cronbach's α = 0.88, test-retest reliability = 0.88). The total scores of ZCMEI-21-Chn had a moderate correlation with a question directly addressing HRQoL (r = 0.40, p < 0.001), EQ-5D descriptive system score (r = 0.57, p < 0.001), and EQ-5D visual analogous scale (r = 0.30, p < 0.001). CONCLUSIONS: The ZCMEI-21-Chn is valid, reliable and culturally adapted to Chinese adult patients with COM. This study offers clinicians an efficient and comprehensive instrument to quantify COM patients' self-reported health outcomes, which could facilitate the standardization of HRQoL data aggregation in COM on a global scale.


Assuntos
Povo Asiático/psicologia , Povo Asiático/estatística & dados numéricos , Doença Crônica/psicologia , Autoavaliação Diagnóstica , Otite Média/psicologia , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria/métodos , Reprodutibilidade dos Testes , Inquéritos e Questionários , Traduções
8.
Ear Nose Throat J ; : 1455613241250185, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801178

RESUMO

Objective: Paradoxical embolism from right-to-left shunting is a common cause of cryptogenic stroke in the young. Circulatory ischemia of the cochlea is closely connected with severe-to-profound sudden sensorineural hearing loss. This study aimed to explore the role of paradoxical embolism in severe-to-profound sudden sensorineural hearing loss in juveniles and young adults. Methods: From August 2021 to September 2022, consecutive outpatients under 35 years of age with severe-to-profound sudden hearing loss were included in the study. Routine auditory electrophysiological testing and contrast transcranial Doppler ultrasonography (c-TCD) were conducted, and the results were retrospectively analyzed. Results: Seven patients (age: 19.4 ± 6.5 years) were enrolled, including 5 juveniles and 2 young adults. Three patients had severe deafness, and 4 patients had profound deafness. Right-to-left shunting was detected in all patients through c-TCD. Patent foramen ovale was found in 2 patients while pulmonary arteriovenous fistula was found in 1 patient through contrast transthoracic echocardiography or cardiac catheterization. No patients had precipitating factors for sudden sensorineural hearing loss, and none had abnormalities on head magnetic resonance imaging. Six patients underwent whole-exome sequencing, and no known deafness gene variant was detected. After standard treatment for 1 month, 2, 3, and 2 patients had complete, slight, and no hearing recovery, respectively. Conclusions: Paradoxical embolism is a possible cause of severe-to-profound sudden sensorineural hearing loss in juveniles and young adults. In young patients, c-TCD is an effective screening tool to detect right-to-left shunting, while contrast transthoracic echocardiography is a complementary examination to c-TCD.

9.
Nanoscale ; 16(5): 2373-2381, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38206313

RESUMO

The electrocatalytic reduction of CO2 to produce formic acid is gaining prominence as a critical technology in the pursuit of carbon neutrality. Nonetheless, it remains challenging to attain both substantial formic acid production and high stability across a wide voltage range, particularly when utilizing bismuth-based catalysts. Herein, we present a novel graphene quantum dot-mediated synthetic strategy to achieve the uniform deposition of highly dispersed bismuth nanoparticles on porous graphene. This innovative design achieves an elevated faradaic efficiency for formate of 87.0% at -1.11 V vs. RHE with high current density and long-term stability. When employing a flow cell, a maximum FEformate of 80.0% was attained with a total current density of 156.5 mA cm-2. The exceptional catalytic properties can be primarily attributed to the use of porous graphene as the support and the auxiliary contribution of graphene quantum dots, which enhance the dispersion of bismuth nanoparticles. This improved dispersion, in turn, has a significantly positive impact on CO2 activation and the generation of *HCOO intermediates to facilitate the formation of formate. This work presents a straightforward technique to create uniform metal nanoparticles on carbon materials for advancing various electrolytic applications.

10.
Adv Healthc Mater ; : e2401371, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38994663

RESUMO

Iontophoretic transdermal drug delivery (TDD) devices are known to enhance the transdermal transport of drugs. However, conventional transdermal iontophoretic devices require external power sources, wired connections, or mechanical parts, which reduce the comfort level for patients during extended use. In this work, a self-powered, wearable transdermal iontophoretic patch (TIP) is proposed by harvesting ambient humidity for energy generation, enabling controlled TDD. This patch primarily uses moist-electric generators (MEGs) as its power source, thus obviating the need for complex power management modules and mechanical components. A single MEG unit can produce an open-circuit voltage of 0.80 V and a short-circuit current of 11.65 µA under the condition of 80% relative humidity. Amplification of the electrical output is feasible by connecting multiple generator units in series and parallel, facilitating the powering of certain commercial electronic devices. Subsequently, the MEG array is integrated with the TDD circuit to create the wearable TIP. After 20 min of application, the depth of drug penetration through the skin is observed to increase threefold. The effective promotion effect of TIP on the transdermal delivery of ionized drugs is corroborated by simulations and experiments. This wearable TIP offers a simple, noninvasive solution for TDD.

11.
Otol Neurotol ; 45(7): e532-e540, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38956761

RESUMO

OBJECTIVES: This study aimed to establish the minimal clinically important difference (MCID) and assess the responsiveness of the Chinese version of Zurich Chronic Middle Ear Inventory (ZCMEI-21-Chn). STUDY DESIGN: Prospective multicenter study. SETTING: Four Chinese tertiary referral centers admitting patients nationwide. PATIENTS: 230 adult patients with chronic otitis media (COM) undergoing tympanoplasty. INTERVENTION: Patients were required to complete the ZCMEI-21-Chn to measure health-related quality of life both preoperatively and postoperatively. An anchor-based method was used to determine the MCID of the derivative cohort by including the Global Rating of Change Questionnaire as an anchor. The generalizability and consistency with functional outcomes of the MCID estimates were externally examined in a validation cohort using a receiver operating characteristic curve analysis. RESULTS: A total of 161 and 69 patients were included in the derivative and validation cohort. The mean preoperative and postoperative ZCMEI-21-Chn total scores were 28.4 (standard deviation [SD] 14.5) and 17.5 (SD 12.6). The mean change in ZCMEI-21-Chn score was 10.9 (SD 14.3, p < 0.001). The MCIDs of the ZCMEI-21-Chn for improvement and deterioration were estimated at 13 (SD 13.0) and -7 (SD 12.9), accordingly. For patients who have reported an improved health-related quality of life, a cutoff value of 15.6 dB HL for elevation of the air-conducted hearing threshold was noticed. However, change of clinical importance judged according to MCID and Japan Otological Society criteria disagreed with each other, notably with a Cohen's kappa ( κ ) of 0.14 ( p = 0.21) in the validation cohort. CONCLUSION: This study is the first to establish the MCID of a COM-specific questionnaire in Chinese. For the COM population undergoing surgical intervention, MCID values of 13 for improvement and -7 for deterioration are recommended. The results were externally validated to be generalizable to nationwide usage, yet distinguishable from the audiological criteria. The availability of the MCID greatly adds to the clinical utility of the ZCMEI-21-Chn by enabling a clinically meaningful interpretation of its score changes.


Assuntos
Diferença Mínima Clinicamente Importante , Otite Média , Qualidade de Vida , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Estudos Prospectivos , Doença Crônica , Inquéritos e Questionários/normas , Otite Média/cirurgia , Timpanoplastia/métodos , Idoso , China , Reprodutibilidade dos Testes , Resultado do Tratamento
12.
J Clin Transl Hepatol ; 11(1): 231-243, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36406320

RESUMO

Hepatocellular carcinoma (HCC) is one of the most commonly diagnosed cancers and a leading cause of cancer-related mortality worldwide, but its pathogenesis remains largely unknown. Nevertheless, genomic instability has been recognized as one of the facilitating characteristics of cancer hallmarks that expedites the acquisition of genetic diversity. Genomic instability is associated with a greater tendency to accumulate DNA damage and tumor-specific DNA repair defects, which gives rise to gene mutations and chromosomal damage and causes oncogenic transformation and tumor progression. Histone deacetylases (HDACs) have been shown to impair a variety of cellular processes of genome stability, including the regulation of DNA damage and repair, reactive oxygen species generation and elimination, and progression to mitosis. In this review, we provide an overview of the role of HDAC in the different aspects of DNA repair and genome instability in HCC as well as the current progress on the development of HDAC-specific inhibitors as new cancer therapies.

13.
Adv Sci (Weinh) ; 10(11): e2207298, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36782105

RESUMO

The growing demand for sustained self-powered devices with multifunctional sensing networks is one of the main challenges for smart textiles, which are the critical elements for the future Internet of Things (IoT) and Point of Care (POC). Here, cellulose-based smart textile is integrated with dynamic Schottky diode (DSD) to generate sustained power source (current density of 8.9 mA m⁻2 ) for self-powered built-in sensing network. In response to normal and shear motions, a pressure sensor with a sensitivity of 0.12 KPa⁻1 and an impact sensor are demonstrated, respectively. The woven structure of the textile contributes to signal amplification, which can also form a matrix of sensing elements for distributed sensing. The proposed strategy of fabricating self-powered and multifunctional sensing networks with smart textiles shows tremendous potential for future intelligent society.

14.
J Biomol Struct Dyn ; : 1-13, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37811547

RESUMO

Numerous studies have shown that hand, foot and mouth disease (HFMD) pathogen Coxsackievirus A16 (CVA16) can also cause severe neurological complications and even death. Currently, there is no effective drugs and vaccines for CVA16. Therefore, developing a drug against CVA16 has become critical. In this study, we conducted two strategies-virtual screening (VS) and fragment replacement to obtain better candidates than the known drug GPP3. Through VS, 37 candidate drugs were screened (exhibiting a lower binding energy than GPP3). After toxicity evaluations, we obtained five candidates, analysed their binding modes and found that four candidates could enter the binding pocket of the GPP3. In another strategy, we analysed the four positions in GPP3 structures by the FragRep webserver and obtained a large number of candidates after replacing different functional groups, we obtained eight candidates (that target the four positions above) with the combined binding score and synthetic accessibility evaluations. AMDock software was uniformly utilized to perform molecular docking evaluation of the candidates with binding activity superior to that of GPP3. Finally, the selected top three molecules (Lapatinib, B001 and C001) and its interaction with CAV16 were validated by molecular dynamics (MD) simulation. The results indicated that all three molecules retain inside the pocket of CAV16 receptor throughout the simulation process, and he binding energy calculated from the MD simulation trajectories also support the strong affinity of the top three molecules towards the CVA16. These results will provide new ideas and technical guidance for designing and applying CVA16 therapeutics.Communicated by Ramaswamy H. Sarma.


HIGHLIGHTSThe dual strategies of computer-aided VS and fragment replacement were first used to obtain candidate small molecules with stronger binding activity than the hand-foot-mouth COV16 viral drug molecule GPP3.The binding patterns of GPP3 and several candidate molecules obtained by VS were analyzed, and a new and interesting binding pattern was found ­ binding at the entrance of the pocket instead of inside the pocket.The Top3 candidate molecules were verified by MD simulations.Through molecular docking, a comprehensive comparative analysis was conducted between all candidate molecules obtained in this study and anti-hand-foot-mouth virus drugs used in clinic.

15.
Science ; 381(6662): 1098-1104, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37676942

RESUMO

Membranes with molecular-sized, high-density nanopores, which are stable under industrially relevant conditions, are needed to decrease energy consumption for separations. Interfacial polymerization has demonstrated its potential for large-scale production of organic membranes, such as polyamide desalination membranes. We report an analogous ultrafast interfacial process to generate inorganic, nanoporous carbon-doped metal oxide (CDTO) nanofilms for precise molecular separation. For a given pore size, these nanofilms have 2 to 10 times higher pore density (assuming the same tortuosity) than reported and commercial organic solvent nanofiltration membranes, yielding ultra-high solvent permeance, even if they are thicker. Owing to exceptional mechanical, chemical, and thermal stabilities, CDTO nanofilms with designable, rigid nanopores exhibited long-term stable and efficient organic separation under harsh conditions.

16.
Adv Sci (Weinh) ; 10(18): e2300340, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37092566

RESUMO

The energy crisis has arisen as the most pressing concern and top priority for policymakers, with buildings accounting for over 40% of global energy consumption. Currently, single-function envelopes cannot satisfy energy efficiency for next-generation buildings. Designing buildings with high mechanical robustness, thermal insulation properties, and more functionalities has attracted worldwide attention. Further optimization based on bioinspired design and material efficiency improvement has been adopted as effective approaches to achieve satisfactory performance. Herein, inspired by the strong and porous cuttlefish bone, a cement aerogel through self-assembly of calcium aluminum silicate hydrate nanoparticles (C-A-S-H, a major component in cement) in a polymeric solution as a building envelop is developed. The as-synthesized cement aerogel demonstrates ultrahigh mechanical performance in terms of stiffness (315.65 MPa) and toughness (14.68 MJ m-3 ). Specifically, the highly porous microstructure with multiscale pores inside the cement aerogel greatly inhibits heat transfer, therefore achieving ultralow thermal conductivity (0.025 W m-1 K-1 ). Additionally, the inorganic C-A-S-H nanoparticles in cement aerogel form a barrier against fire for good fire retardancy (limit oxygen index, LOI ≈ 46.26%, UL94-V0). The versatile cement aerogel featuring high mechanical robustness, remarkable thermal insulation, light weight, and fire retardancy is a promising candidate for practical building applications.


Assuntos
Alumínio , Nanopartículas , Cálcio , Carbono , Temperatura Alta
17.
Ann Med ; 55(1): 2227844, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37354023

RESUMO

BACKGROUND: Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are widely used for industrial and commercial purposes and have received increasing attention due to their adverse effects on health. OBJECTIVE: To examine the relationship of serum PFAS and glycometabolism among adolescents based on the US National Health and Nutrition Examination Survey. METHODS: General linear regression models were applied to estimate the relationship between exposure to single PFAS and glycometabolism. Weighted quantile sum (WQS) regression models and Bayesian kernel machine regressions (BKMR) were used to assess the associations between multiple PFASs mixture exposure and glycometabolism. RESULTS: A total of 757 adolescents were enrolled. Multivariable regression model showed that Me-PFOSA-AcOH exposure was negatively associated with fasting blood glucose. WQS index showed that there was marginal negative correlation between multiple PFASs joint exposure and the homeostasis model of assessment for insulin resistance index (HOMA-IR) (ß = -0.26, p < .068), and PFHxS had the largest weight. BKMR models showed that PFASs mixture exposure were associated with decreased INS and HOMA-IR, and the exposure-response relationship had curvilinear shape. CONCLUSIONS: The increase in serum PFASs were associated with a decrease in HOMA-IR among adolescents. Mixed exposure models could more accurately and effectively reveal true exposure.Key MessagesThe detection rates of different PFAS contents in adolescent serum remained diverse.Adolescent serum PFASs had negative curvilinear correlation with INS and HOMA-IR levels.PFHxS had the highest weight in the associations between multiple PFASs and adolescent glycometabolism.


Assuntos
Poluentes Ambientais , Fluorocarbonos , Humanos , Adolescente , Poluentes Ambientais/efeitos adversos , Poluentes Ambientais/análise , Inquéritos Nutricionais , Teorema de Bayes , Fluorocarbonos/efeitos adversos , Insulina
18.
Sci Total Environ ; 880: 163238, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37011677

RESUMO

Soil quality (SQI) is a comprehensive indicator reflecting the agricultural productivity of soil, and soil ecosystem multifunctionality (performing multiple functions simultaneously; EMF) can reflect complex biogeochemical processes. However, the effects of enhanced efficiency nitrogen fertilizers (EENFs; urease inhibitors (NBPT), nitrification inhibitors (DCD), and coated controlled-release urea (RCN)) application on the SQI and soil EMF and their relationships are still unclear. Therefore, we conducted a field experiment to study the effects of different EENFs on the SQI, enzyme stoichiometry and soil EMF in semiarid areas of Northwest China (Gansu, Ningxia, Shaanxi, Shanxi). Across the four study sites, DCD and NBPT increased SQI by 7.61-16.80 % and 2.61 %-23.20 % compared to mineral fertilizer, respectively. N fertilizer application (N200 and EENFs) alleviated microbial N limitation, and EENFs alleviated microbial N and C limitations to a greater extent in Gansu and Shanxi. Moreover, nitrogen inhibitors (Nis; DCD and NBPT) improved the soil EMF to a greater extent than N200 and RCN, DCD increased by 205.82-340.00 % and 145.00-215.47 % in Gansu and Shanxi, respectively; NBPT increased by 332.75-778.59 % and 364.44-929.62 % in Ningxia and Shanxi, respectively. A random forest model showed that the microbial biomass carbon (MBC), microbial biomass nitrogen (MBN) and soil water content (SWC) of the SQI factors were the main driving forces of soil EMF. Moreover, SQI improvement could alleviate microbial C and N limitations and promote the improvement of soil EMF. It is worth noting that soil EMF was mainly affected by microbial N limitation rather than C limitation. Overall, NIs application is an effective way to improve the SQI and soil EMF in the semiarid region of Northwest China.


Assuntos
Ecossistema , Solo , Solo/química , Nitrogênio/análise , Fertilizantes/análise , Urease , Microbiologia do Solo , Carbono
19.
J Colloid Interface Sci ; 637: 94-103, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36689801

RESUMO

Iron-cobalt dual single-atom anchoring on nitrogen-doped graphene (FexCoy-NG) improves the efficiency of migration and separation of photo-generated carriers. In this work, the perylene diimide (PDI) is self-assembled on the FexCoy-NG to form the FexCoy-NG/PDI composites by π-π interaction, which is reported for the first time. The bisphenol A (BPA) degradation of optimized 20% Fe0.2Co0.8-NG/PDI are nearly 100%, and the degradation rate is 1.5 and 12.7 times that of the self-assembled PDI and commercial-grade PDI. The high degradation performance by FexCoy-NG/PDI are mainly due to: (i) regulating the proportion of Fe-Co dual active sites content, so that it can achieve the synergistic interaction to facilitate the transfer of electrons in the catalytic reaction. (ii) PDI is uniformly dispersed by adding the FexCoy-NG, which increases the specific surface area of composites to adsorb more pollutants. Free radical trapping experiments and electron spin-resonance spectroscopy characterization confirmed that the O2-, OH, 1O2 and h+ are the main reactive species (RSs) for BPA degradation. Under the attack of RSs, BPA completes the processes of hydroxylation, demethylation, aromatization, ring-opening, and finally complete mineralization into CO2 and H2O. These results revealed that Fe0.2Co0.8-NG/PDI photocatalysts may be efficiently applied for the remediation of phenol contaminated natural waters.

20.
Huan Jing Ke Xue ; 44(3): 1542-1552, 2023 Mar 08.
Artigo em Zh | MEDLINE | ID: mdl-36922215

RESUMO

In order to clarify the differences in the effects of vegetation restoration strategies on soil carbon sequestration and aggregate stability under different water-eroded environments, we collected experimental data from 91 papers and evaluated the response of soil organic carbon (SOC) stock and aggregate stability to vegetation restoration based on Meta-analysis. The results showed the following:① compared with cropland or bare land, forestland/grassland restoration was beneficial to increase SOC stock and improve aggregate stability, but the dominant functions of the two were different. The effect of forestland restoration on carbon sequestration was stronger than that of grassland reforestation, and the effect of grassland restoration on aggregate stability was stronger than that of forestland restoration. ② Multi-factor Meta-analysis showed that the factors that significantly affected SOC were restoration year, soil clay content, vegetation coverage, mean annual precipitation (MAP), mean annual temperature (MAT), and soil depth. The positive effect of vegetation restoration on SOC stock increased with the increase in vegetation coverage rate. Grassland restoration had a more significant effect on SOC stock when soil clay content was 20%-32%, it was more likely to promote the carbon sequestration effect of grassland when MAP>800 mm or MAT<15℃, and there was no significant change in SOC stock under different restoration years. However, the effect of forestland restoration on SOC stock was more significant when soil clay content was>32%. Climate conditions had no limited effect on SOC stock in forestland, and there was a positive effect between SOC stock under forestland restoration and restoration years. ③ Vegetation restoration had stronger significant positive effects on mean weight diameter (MWD) and mean geometric diameter (GMD) when the clay content was 20%-32%, and MWD and GMD increased with the increase in vegetation coverage. ④SOC stock growth could explain 25% and 24% of the variation in the effect value of MWD and GMD, respectively. These results indicated that the formation of SOC was the result of multiple factors, and soil aggregate stability was limited only by vegetation coverage and soil clay content. The increase in SOC stock could promote the improvement of water stability MWD and GMD. These results can clarify the carbon sequestration effect of different vegetation restoration measures in water-eroded environments and provide theoretical reference for the restoration and reconstruction of degraded ecosystems.

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