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1.
Front Endocrinol (Lausanne) ; 15: 1435102, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39359414

RESUMEN

Background: It is challenging for clinicians to distinguish adrenocortical carcinoma (ACC) from benign adrenocortical adenomas (ACA) in their early stages. This study explored the value of serum steroid profiling as a complementary biomarker for malignancy diagnosis of ACC other than diameter and explored the influence of sex and functional status. Methods: In this retrospective study, a matched cohort of patients diagnosed with either ACC or ACA based on histopathology was meticulously paired in a 1:1 ratio according to sex, age, and functional status. Eight serum steroids including 11-deoxycortisol, 11-deoxycorticosterone, progesterone, androstenedione, dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), 17-hydroxyprogesterone, and estradiol, were quantified by liquid chromatography tandem mass spectrometry. We conducted a comparative analysis of the clinical characteristics and serum steroid profiles of patients with ACC and ACA, with further subgroup analysis. Results: The study included 31 patients with ACC and 31 matched patients with ACA. Patients with ACC exhibited significantly larger tumor diameters, lower body mass index (BMI), and higher levels of 11-deoxycortisol, progesterone, and androstenedione than those with ACA. 11-deoxycortisol was the only valuable index for discriminating ACC from ACA, regardless of functional status and sex. Progesterone, DHEA, and DHEAS levels were higher in the functional ACC group than in the non-functional ACC group. Female ACC patients, especially in postmenopausal female exhibited higher levels of androstenedione than male patients. The area under the curve of tumor diameter, 11-deoxycortisol, and BMI was 0.947 (95% CI 0.889-1.000), with a sensitivity of 96.8% and specificity of 90.3%. Conclusion: Serum steroid profiling serves as a helpful discriminative marker for ACC and ACA, with 11-deoxycortisol being the most valuable marker. For other steroid hormones, consideration of sex differences and functional status is crucial.


Asunto(s)
Neoplasias de la Corteza Suprarrenal , Adenoma Corticosuprarrenal , Carcinoma Corticosuprarrenal , Humanos , Masculino , Femenino , Neoplasias de la Corteza Suprarrenal/sangre , Neoplasias de la Corteza Suprarrenal/diagnóstico , Neoplasias de la Corteza Suprarrenal/patología , Carcinoma Corticosuprarrenal/sangre , Carcinoma Corticosuprarrenal/diagnóstico , Persona de Mediana Edad , Estudios Retrospectivos , Adenoma Corticosuprarrenal/sangre , Adenoma Corticosuprarrenal/diagnóstico , Adenoma Corticosuprarrenal/patología , Adulto , Esteroides/sangre , Diagnóstico Diferencial , Anciano , Biomarcadores de Tumor/sangre , Factores Sexuales
2.
J Orthop Surg Res ; 19(1): 634, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39380111

RESUMEN

BACKGROUND: The repair of diabetic foot defects (DFD) is a major challenge in clinical practice. The purpose of this study was to investigate the difference in clinical efficacy of different flap techniques in repairing DFD wounds, and to compare the difference in clinical efficacy of anterolateral thigh perforator flap (ALTP) in repairing DFD and non-DFD. METHODS: This study is a retrospective clinical study of different types of flap reconstruction in patients with DFD admitted to our hospital from January 2010 to December 2021. A total of 40 patients with DFD and 43 patients with non-DFD were included in this study. Detailed preoperative basic information, intraoperative details, postoperative complications and long-term follow-up results were collected. RESULT: The comorbidities, wound infection and wound duration of DFD group were more serious than those of non-DFD group. In addition, the incidence of complications was higher in DFD group, the wound healing time was longer, the aesthetic evaluation, the functional recovery rate of ankle joint and the sensory recovery effect of flaps were worse. CONCLUSION: In this study, it is concluded that different flap techniques can obtain better clinical efficacy in repairing DFD wounds. Compared with non-DFD wounds, the postoperative risk of DFD wounds using free ALTP flaps is higher, but the risk can be reduced by reasonable preoperative vascular examination. Free flap can deal with various irregular wounds and provide more options for clinical repair. LEVEL OF EVIDENCE: III, Case-control study.


Asunto(s)
Pie Diabético , Procedimientos de Cirugía Plástica , Humanos , Pie Diabético/cirugía , Masculino , Femenino , Persona de Mediana Edad , Estudios Retrospectivos , Anciano , Procedimientos de Cirugía Plástica/métodos , Resultado del Tratamiento , Colgajo Perforante , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/epidemiología , Colgajos Quirúrgicos , Cicatrización de Heridas , Estudios de Seguimiento , Adulto , Muslo/cirugía
3.
J Plast Reconstr Aesthet Surg ; 98: 272-280, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39305535

RESUMEN

BACKGROUND: Chronic osteomyelitis poses a formidable challenge for orthopedic practitioners in clinical practice. Chimeric perforator flap is a commonly used repair method for chronic osteomyelitis. The purpose of this study was to compare the clinical efficacy of chimeric anterolateral thigh flap (C-ALTP) and chimeric thoracodorsal artery perforator flap (C-TDAP) for the treatment of chronic osteomyelitis. METHODS: A retrospective analysis was performed on patients with chronic osteomyelitis of the lower extremity who underwent two kinds of treatment with chimeric perforator flaps from January 2014 to March 2022. The preoperative basic data and the operative and postoperative basic information of the two groups were collected and statistically analyzed. RESULTS: Sixty-six patients were included in this study, and both groups achieved satisfactory aesthetic and functional results. Intraoperative results showed that the intraoperative blood loss and flap acquisition time in the C-TDAP group were less than those in the C-ALTP group. The incidence of postoperative complications in the donor and recipient sites in the C-TDAP group was significantly lower than that in the C-ALTP group, which led to a high reoperation rate in the C-ALTP group. Long-term follow-up showed that the wound healing time and weight-bearing walking time in the C-TDAP group were less than those in the C-ALTP group. CONCLUSIONS: Chimeric perforator flaps can effectively be used to treat osteomyelitis with composite tissue defects, eliminate inflammation of the affected limbs, and promote wound healing. However, C-TDAP flaps have more reliable healing effects on wounds and donor sites, and have fewer complications. LEVEL OF EVIDENCE: III, Case-control study.

4.
J Orthop Surg Res ; 19(1): 533, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39218944

RESUMEN

BACKGROUND: The reconstruction of complex wounds of the hand still has challenges in achieving aesthetic, functional and sensory recovery. We presented our experience of using the polyfoliate and chimeric radial collateral artery perforator flaps (RCAPF) to repair complex hand defects, aiming to explore the feasibility of special-form RCAPFs in hand coverage and enhance the comprehension of their respective indications. METHODS: From June 2014 to March 2021, 26 cases (19 males and 7 females, mean 44.4 years) underwent defect and sensation reconstruction of their hands with special-form RCAPFs, which manifested as multiple adjacent or irregular single wounds and composite tissue defects complicated with a degree of nerve injury. The clinical effects of the free RCAPFs were evaluated by integrating the postoperative and long-term follow-up outcomes of all cases. RESULTS: Altogether 8 polyfoliate flaps, 17 chimeric flaps and 1 polyfoliate-chimeric flap were harvested. Of them, 23 flaps survived uneventfully in one stage. Venous congestion occurred in 3 cases, two of which survived through vascular exploration and another one was finally repaired by the contralateral RCAPF. The follow-up results showed that the appearance of both the recipient and donor sites mostly recovered satisfactory. All the bone flaps properly healed. The BMRC sensory evaluation results of all skin flaps were S4 in 8 flaps, S3 in 18 flaps, and S2 in 9 flaps. CONCLUSIONS: The free RCAPFs can be designed in various forms with a reliable blood supply, contributing to reconstructing simple and multiple wounds of the hand with or without bone defects and dead space.


Asunto(s)
Traumatismos de la Mano , Colgajo Perforante , Procedimientos de Cirugía Plástica , Arteria Radial , Humanos , Femenino , Masculino , Colgajo Perforante/irrigación sanguínea , Adulto , Persona de Mediana Edad , Procedimientos de Cirugía Plástica/métodos , Arteria Radial/trasplante , Traumatismos de la Mano/cirugía , Mano/cirugía , Mano/irrigación sanguínea , Adulto Joven , Estudios de Seguimiento , Resultado del Tratamiento , Estudios de Factibilidad
5.
Nat Commun ; 15(1): 6004, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-39019867

RESUMEN

Triboelectric nanogenerator (TENG) operates on the principle of utilizing contact electrification and electrostatic induction. However, visualization and standardized quantification of surface charges for triboelectric materials remain challenging. Here, we report a surface charge visualization and standardized quantification method using electrostatic surface potential measured by Kevin probe and the iterative regularization strategy. Moreover, a tuning strategy on surface charge is demonstrated based on the corona discharge with a three-electrode design. The long-term stability and dissipation mechanisms of the injected negative or positive charges demonstrate high dependence on deep carrier traps in triboelectric materials. Typically, we achieved a 70-fold enhancement on the output voltage (~135.7 V) for the identical polytetrafluoroethylene (PTFE) based TENG (neg-PTFE/PTFE or posi-PTFE/PTFE triboelectric pair) with stable surface charge density (5% decay after 140 days). The charged PTFE was demonstrated as a robot e-skins for non-contact perception of object geometrics. This work provides valuable tools for surface charge visualization and quantification, giving a new strategy for a deeper understanding of contact electrification.

6.
Sci Total Environ ; 946: 174105, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-38908601

RESUMEN

When smelting silicon manganese alloy in an industrial electric furnace, it will produce smoke and dust waste gas, which can be utilized again back to the furnace and improve the utilization rate of raw materials after a particular trapping device and collection treatment. However, at higher moisture levels, they are prone to explode. Effects of various initial masses, initial moisture contents, and microwave output powers on the soot ash of smelting silicon manganese alloy were studies. The findings indicate that the microwave drying rate increases with all three variables. The time for complete microwave drying is directly proportional to the sample's initial moisture content and the sample's initial mass, and the time for complete microwave drying is inversely proportional to the microwave output power. The results demonstrate that the Modified Page model can accurately describe the microwave drying process. The experimental data were fitted experimentally by drying kinetic models. Microscopic characterization of soot ash from refining silico­manganese alloys before and after drying was carried out using FTIR and SEM. Through FTIR characterization, the peak value of the -OH absorption peak decreases upon drying, and SEM results in no agglomeration caused by microwave drying and better dispersion of the soot ash of the dried smelted silica­manganese alloys, all of which proved that microwaves could effectively remove water. It was discovered that the diffusion coefficient increased gradually with increasing power when it was computed using Fick's second law. The diffusion coefficient increases and then decreases as the moisture content increases. The diffusion coefficient decreases as the initial mass increases. Activation energy of microwave drying of soot ash from the refining of silicomanganese alloys was calculated to be -1.4467 W/g. Its purpose is to offer a detailed guide for the industrial drying of soot ash from silicomanganese alloy refinement using microwave drying technology.

7.
ACS Sens ; 9(6): 2728-2776, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38828988

RESUMEN

The escalating development and improvement of gas sensing ability in industrial equipment, or "machine olfactory", propels the evolution of gas sensors toward enhanced sensitivity, selectivity, stability, power efficiency, cost-effectiveness, and longevity. Two-dimensional (2D) materials, distinguished by their atomic-thin profile, expansive specific surface area, remarkable mechanical strength, and surface tunability, hold significant potential for addressing the intricate challenges in gas sensing. However, a comprehensive review of 2D materials-based gas sensors for specific industrial applications is absent. This review delves into the recent advances in this field and highlights the potential applications in industrial machine olfaction. The main content encompasses industrial scenario characteristics, fundamental classification, enhancement methods, underlying mechanisms, and diverse gas sensing applications. Additionally, the challenges associated with transitioning 2D material gas sensors from laboratory development to industrialization and commercialization are addressed, and future-looking viewpoints on the evolution of next-generation intelligent gas sensory systems in the industrial sector are prospected.


Asunto(s)
Gases , Gases/análisis , Gases/química , Olfato , Industrias , Odorantes/análisis
8.
Sci Rep ; 14(1): 12621, 2024 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824201

RESUMEN

Anaplasma and Ehrlichia are tick-borne bacterial pathogens that cause anaplasmoses and ehrlichioses in humans and animals. In this study, we examined the prevalence of Anaplasma and Ehrlichia species in ticks and domesticated animals in Suizhou County, Hubei Province in the central China. We used PCR amplification and DNA sequencing of the 16S rRNA, groEL, and gltA genes to analyze. We collected 1900 ticks, including 1981 Haemaphysalis longicornis and 9 Rhipicephalus microplus, 159 blood samples of goats (n = 152), cattle (n = 4), and dogs (n = 3) from May to August of 2023. PCR products demonstrated that Anaplasma bovis, Anaplasma capra, and an Ehrlichia species were detected in the H. longicornis with the minimum infection rates (MIR) of 1.11%, 1.32%, and 0.05%, respectively; A. bovis, A. capra, and unnamed Anaplasma sp. were detected in goats with an infection rate of 26.31%, 1.31% and 1.97%, respectively. Anaplasma and Ehrlichia species were not detected from cattle, dogs and R. microplus ticks. The genetic differences in the groEL gene sequences of the Anaplasma in the current study were large, whereas the 16S rRNA and gltA gene sequences were less disparate. This study shows that ticks and goats in Suizhou County, Hubei Province carry multiple Anaplasma species and an Ehrlichia species, with relatively higher infection rate of A. bovis in goats. Our study indicates that multiple Anaplasma and Ehrlichia species exist in ticks and goats in the central China with potential to cause human infection.


Asunto(s)
Anaplasma , Anaplasmosis , Animales Domésticos , Ehrlichia , Variación Genética , Cabras , ARN Ribosómico 16S , Animales , Anaplasma/genética , Anaplasma/aislamiento & purificación , China/epidemiología , Ehrlichia/genética , Ehrlichia/aislamiento & purificación , Cabras/microbiología , Perros , Bovinos , Anaplasmosis/epidemiología , Anaplasmosis/microbiología , Prevalencia , Animales Domésticos/microbiología , ARN Ribosómico 16S/genética , Garrapatas/microbiología , Ehrlichiosis/epidemiología , Ehrlichiosis/veterinaria , Ehrlichiosis/microbiología , Filogenia
9.
Sci Total Environ ; 931: 172921, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38697533

RESUMEN

Sulfur hexafluoride (SF6), recognized as a potent greenhouse gas with significant contributions to climate change, presents challenges in understanding its degradation processes. Molecular dynamics simulations are valuable tools for understanding modes of decomposition while the traditional approaches face limitations in time scale and require unrealistically high temperatures. The collective variable-driven hyperdynamics (CVHD) approach has been introduced to directly depict the pyrolysis process for SF6 gas at practical application temperatures, as low as 1600 K for the first time. Achieving an unprecedented acceleration factor of up to 107, the method extends the simulation time scale to milliseconds and beyond while maintaining consistency with experimental and theoretical models. The differences in the reaction process between simulations conducted at actual and elevated temperatures have been noted, providing insights into SF6 degradation pathways. The work provides a basis for the further studies on the thermal degradation of pollutants.

10.
Front Public Health ; 12: 1330521, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38510350

RESUMEN

Objective: With increasing rates of anxiety and depression during COVID-19, exercise treatment has drawn attention for its effects on COVID-19 patients with anxiety and depression. This study set out to assess the impact of exercise therapy on COVID-19 patients' anxiety and depression. Methods: PubMed, EMBASE, Web of Science and Cochrane Library were used to search articles about exercise therapy as a means of treating anxiety and depression in COVID-19 patients from inception to April 30, 2023. The risk of bias was assessed by the Cochrane Collaboration bias risk tool. Data were pooled with the random effects model. RevMan version 5.4 was used for the statistical analyses. This work was registered in the PROSPERO database (registration number: CRD42023406439). Selection criteria: Randomized clinical trials (RCTs) of COVID-19 patients with anxiety and depression were included to assess the impact of physical exercise on COVID-19 patients with anxiety and depression. Results: 6 studies including a total of 461 COVID-19 patients were analyzed in this meta-analysis. Overall, the meta-analysis showed that compared with the control group, exercise could significantly improve anxiety (SMD = -0.76; 95%CI: -0.96, -0.55; p < 0.00001), depression level (SMD = -0.39; 95%CI: -0.70, -0.09; p = 0.01), the PHQ-9 score (MD = -1.82; 95%CI: -2.93, -0.71; p = 0.001) and the sleep quality (SMD = -0.73; 95%CI: -1.32, -0.14; p = 0.01) in COVID-19 patients. Conclusion: The research provided evidence that exercise therapy is able to help COVID-19 patients experience less anxiety and depression and have better-quality sleep. Systematic review registration: CRD42023406439.


Asunto(s)
Ansiedad , COVID-19 , Depresión , Terapia por Ejercicio , Humanos , COVID-19/psicología , Depresión/terapia , Ansiedad/terapia , Ensayos Clínicos Controlados Aleatorios como Asunto , SARS-CoV-2
11.
Adv Mater ; : e2314380, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38517171

RESUMEN

Triboelectric nanogenerator (TENG) manifests distinct advantages such as multiple structural selectivity, diverse selection of materials, environmental adaptability, low cost, and remarkable conversion efficiency, which becomes a promising technology for micro-nano energy harvesting and self-powered sensing. Tribo-dielectric materials are the fundamental and core components for high-performance TENGs. In particular, the charge generation, dissipation, storage, migration of the dielectrics, and dynamic equilibrium behaviors determine the overall performance. Herein, a comprehensive summary is presented to elucidate the dielectric charge transport mechanism and tribo-dielectric material modification principle toward high-performance TENGs. The contact electrification and charge transport mechanism of dielectric materials is started first, followed by introducing the basic principle and dielectric materials of TENGs. Subsequently, modification mechanisms and strategies for high-performance tribo-dielectric materials are highlighted regarding physical/chemical, surface/bulk, dielectric coupling, and structure optimization. Furthermore, representative applications of dielectric materials based TENGs as power sources, self-powered sensors are demonstrated. The existing challenges and promising potential opportunities for advanced tribo-dielectric materials are outlined, guiding the design, fabrication, and applications of tribo-dielectric materials.

12.
Langmuir ; 40(14): 7422-7432, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38544283

RESUMEN

Graphene is one of the most promising thermal protection materials for high-speed aircraft due to its lightweight and excellent thermophysical properties. At high Mach numbers, the extremely high postshock temperature would dissociate the surrounding air into a mixture of atomic and molecular components in a highly thermochemical nonequilibrium state, which greatly affects the subsequent thermal chemical reactions of the graphene interface. Through establishing a reactive gas-solid interface model, the reactive molecular dynamics method is employed in this study to reveal the influences of the thermochemical nonequilibrium gas mixture on the thermal oxidation and nitridation mechanisms of graphene sheet. The results show that three distinctive stages can be recognized during bombardment of various nonequilibrium gas components toward the graphene sheet: (i) collision and surface adsorption stage, (ii) gas-solid heterogeneous reaction stage, and (iii) gas phase homogeneous reaction stage. The surface catalysis effect is found to be dominant during the first two stages, which can influence the following ablation behavior of graphene significantly at high-temperature conditions. Moreover, surface catalysis, oxidation, nitridation, and ablation mechanisms between nonequilibrium gas and graphene interface are revealed, which is of high relevance for future interfacial design and application of graphene as a thermal protection material.

13.
Adv Sci (Weinh) ; 11(13): e2307382, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38240464

RESUMEN

Heat dissipation performance is crucial for the operational reliability of industrial equipment, which can be monitored by detecting the wind or airflow temperature of the radiator. The emergence of triboelectric nanogenerators (TENGs) provides new routes for wind energy harvesting and self-powered sensing. Herein, a rotary wind-driven triboelectric nanogenerator (RW-TENG) with soft-contact working mode is newly designed to achieve tunable contact areas by utilizing the reliable thermal response of NiTi shape memory alloy (SMA) to air/wind temperature. The RW-TENG can generate different triboelectric outputs under air stimulation with different speeds or temperatures, which is demonstrated as a power source for online monitoring sensors, self-powered wind speed sensing, and airflow temperature monitoring. Specifically, a self-powered sensor of wind speed is demonstrated with a sensitivity of 0.526 µA m-1 s between 2.2 and 19.6 m s-1, and a self-powered monitoring device of high airflow temperature, which show relatively short response time (109 s), strong anti-interference ability and outstanding long-term durability. This study introduces an innovative route for real-time detection of airflow temperature in wind-cooled industrial equipment, showing broad application prospects for information perception and intelligent sensing of the industrial IoTs.

14.
Int Wound J ; 21(3): e14462, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37931597

RESUMEN

Ultrasound (US) has traditionally been recognised for its imaging capabilities, but its emerging role as a therapeutic modality in postoperative wound management, especially in paediatric care, has garnered significant attention. This meta-analysis aimed to evaluate the influence of US on postoperative wound healing and infection rates in paediatric patients. From an initial pool of 1236 articles, seven were deemed suitable for inclusion. Postoperative wound healing was assessed using the Redness, Edema, Ecchymosis, Discharge, and Approximation (REEDA) scale. Notably, there was a significant difference in wound healing patterns between the US-treated and control groups (I2 = 94%, standardized mean difference [SMD]: -4.60, 95% confidence intervals [CIs]: -6.32 to -2.88, p < 0.01), as illustrated in Figure 4. Additionally, a marked difference in wound infection rates was observed between the groups (I2 = 93%, SMD: -5.86, 95% CIs: -9.04 to -2.68, p < 0.01), as portrayed in Figure 5. The findings underscore the potential benefits of US in enhancing postoperative wound healing and reducing infection rates in paediatric surgical settings. However, the application of US should be judicious, considering the nuances of individual patient needs and clinical contexts.

15.
DNA Cell Biol ; 42(10): 638-644, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37851024

RESUMEN

Developmental dysplasia of the hip (DDH), characterized by acetabular deformity that manifests from loose ligaments to complete dislocation of the hip, can cause notable pain and dysfunction and lead to hip dislocation, secondary fractures, scoliosis, and osteoarthritis of hip. Variants in FLNA may produce a spectrum of malformations in multiple organs, especially the skeleton. This study aimed to identify the genetic etiologies of DDH patients and provide genetic testing information for further diagnosis and treatment of DDH. We recruited a Chinese woman with DDH and her family members. Whole-exome sequencing was used to identify the patient's genetic etiologies. Protein models were used to analyze the pathogenic mechanism of the identified variants. A novel variant (c.3493T>G, p.C1165G) of FLNA was detected. The structural models of the mutant FLNA protein indicated that the variant would lose its sulfhydryl side chain and destroy the attraction between benzene rings and sulfhydryl. We reported a novel variant (c.3493T>G, p.C1165G) of FLNA in a Chinese woman with DDH. Our research outcome enriches the gene pool for hip dysplasia and emphasizes the pathogenicity of sulfhydryl side chain disruption in FLNA.


Asunto(s)
Displasia del Desarrollo de la Cadera , Luxación Congénita de la Cadera , Femenino , Humanos , Benceno , Displasia del Desarrollo de la Cadera/complicaciones , Displasia del Desarrollo de la Cadera/genética , Filaminas/genética , Pruebas Genéticas , Luxación Congénita de la Cadera/genética , Luxación Congénita de la Cadera/complicaciones , Luxación Congénita de la Cadera/diagnóstico , Estudios Retrospectivos
16.
J Mol Model ; 29(11): 350, 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37880557

RESUMEN

CONTEXT: SF6 gas has a strong greenhouse effect, and how to treat SF6 in an environmentally friendly way has been a hot topic of current research. In this paper, the adsorption behavior of SF6 on the surface of Pd-doped hydroxyl-terminated modified Ti3C2Tx (i.e., Ti3C2(OH)2) was investigated based on the density functional theory using two-dimensional MXene as the catalyst. The structures of different Pd-doped Ti3C2(OH)2 were analyzed and the most structurally stable doped structures were selected as the basis for subsequent calculations. A large number of adsorption configurations were constructed and geometrically optimized, and the adsorption energy, charge transfer, differential charge density, and density of states of the systems were calculated in order to analyze the gas-solid interactions and find the surface active sites; compared with the adsorption performance of undoped Ti3C2(OH)2 on SF6, it was found that Pd doping played a less inhibitory role in the adsorption of SF6 on the Ti3C2(OH)2 surface. The results of this study can provide theoretical support for the use of Pd-doped Ti3C2(OH)2 as a catalyst for the degradation of SF6. METHODS: In this paper, simulations of SF6 adsorption on Ti3C2Tx surfaces are based on density functional theory and are carried out in the Dmol3 module of Material Studio. To better describe the non-uniform electron density of the actual system, the PBE functional in the generalized gradient approximation (GGA) was chosen for the optimization of the structure of the gas-solid interface system and the calculation of the relevant electronic properties, combined with the Grimme dispersion correction in the DFT-D dispersion correction for the electron exchange correlation term. Because both Pd and Ti are transition metal elements, the mode-conserving pseudopotential DNP basis set containing relativistic effects was chosen for the electronic wave function expansion. In this paper, an all-electron model is used for the inner core treatment of gas molecules and a density generalized semi-nuclear pseudopotential DSSP is used for the solid surface treatment.

17.
AoB Plants ; 15(5): plad067, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37899981

RESUMEN

Staminal hairs are the particular appendages of stamens, which may affect pollinator foraging behaviour and pollen transfer. However, experimental evidence of the functions of staminal hairs in pollination remains scarce. Here, we conducted staminal hair manipulation experiments in Tradescantia fluminensis (Commelinaceae) to investigate their effects on visitation and pollen transfer by bees. Our observations revealed that both visitation rates and visit duration of honeybees (Apis cerana) to control flowers were significantly higher than that of hairless flowers. Moreover, removing the staminal hairs significantly decreased pollen deposition by honeybees (A. cerana), but did not affect pollen removal. The staminal hair was similar in length to the stamen and the pistil of T. fluminensis. The staminal hairs provide more footholds for honeybees, and they lay prone on the staminal hairs to collect pollen, which increased the accuracy of pollination through the consistent pollen placement and pick-up on the ventral surface of honeybees. These results showed that the staminal hairs in T. fluminensis may represent an adaptation to attract pollinators and enhance pollination accuracy.

18.
Nanotechnology ; 35(3)2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37666245

RESUMEN

SF6/N2mixture is an alternative gas of SF6, which is already used in electrical equipment. When a malfunction occurs , SF6/N2will decompose and further react with trace water and oxygen to produce nitrogen-containing gases such as NO, NO2, N2O and NF3. It is necessary to monitor these gases to ensure the safe operation of the equipment. This paper is based on density functional theory (DFT), the nanomaterial Ti3C2Txdoped with Au atom was selected as sensing material. The result shows that Au/Ti3C2Txhas larger adsorption energy when NO and NO2adsorbed on the surface, the stable structures were conformed more easily with NO and NO2compared with N2O and NF3. The density of states analysis and the frontier molecule orbital analysis reveal more change of the system before and after NO and NO2adsorption, suggesting the material showed good sensitivity performance to NO and NO2. Thus, Au/Ti3C2Txis considered to have the potential for sensing NO and NO2.

19.
Opt Lett ; 48(18): 4849-4852, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37707919

RESUMEN

We propose a model-enhanced network with unpaired single-shot data for solving the imaging blur problem of an optical sparse aperture (OSA) system. With only one degraded image captured from the system and one "arbitrarily" selected unpaired clear image, the cascaded neural network is iteratively trained for denoising and restoration. With the computational image degradation model enhancement, our method is able to improve contrast, restore blur, and suppress noise of degraded images in simulation and experiment. It can achieve better restoration performance with fewer priors than other algorithms. The easy selectivity of unpaired clear images and the non-strict requirement of a custom kernel make it suitable and applicable for single-shot image restoration of any OSA system.

20.
Materials (Basel) ; 16(16)2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37629838

RESUMEN

In the hydrometallurgical process of zinc production, the residue from the leaching stage is an important intermediate product and is treated in a Waelz kiln to recover valuable metals. To ensure optimal results during the Waelz kiln process, it is necessary to pre-treat the residues by drying them first due to their higher water content. This work studies the residue's drying process using microwave technology. The study results indicate that microwave technology better removes the residue's oxygen functional groups and moisture. The dehydration process's effective diffusion coefficient increases as the microwave's heating power, the initial moisture content, and the initial mass increase. The Page model is appropriate for imitating the drying process, and the activation energy of the drying process for the residues is -13.11217 g/W. These results indicate that microwave technology efficiently dries the residues from the leaching stage. Furthermore, this study provides a theoretical basis and experimental data for the industrial application of microwave drying.

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