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1.
Phys Chem Chem Phys ; 26(20): 14847-14856, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38727050

RESUMEN

MXenes have attracted substantial attention for their various applications in energy storage, sensors, and catalysts. Experimental exploration of MXenes with hybrid terminal surfaces offers a unique means of property tailoring that is crucial for expanding the performance space of MXenes, wherein the formation energy of an MXene with mixed surface terminals plays a key role in determining its relative stability and practical applications. However, the challenge of identifying energetically stable MXenes with multifunctional surfaces persists, primarily due to the absence of precise surface modification during experiments and the vast structural space for DFT calculations. Herein, we use an all-fixed transfer (AFT) framework combined with first-principles calculations to predict the formation energies of MXenes terminated by binary elements from groups VIA and VIIA. The trained model exhibits a high average R2 of 0.99, maintaining transferability and accuracy in predicting larger supercells from smaller-sized MXenes and datasets despite the structural imbalance between the training and prediction sets. The underlying interpretation of the high accuracy is revealed through the capture of main attributes and comparison of node features. Additionally, it is important to mention that the factors influencing the average formation energy include the types of element pairs, the ratio of terminal groups, and the distribution of terminations on two surfaces, with the first one being dominant. Finally, we successfully streamline the diverse structural cardinality of a large hybrid terminated MXene space of over 700 million, thereby facilitating the rapid screening of the top 5 stable MXene classes with binary terminal elements (FO, FCl, FBr, FS, and FSe). Besides, in the scenarios of lithium storage, the TL-predicted MXene can enhance its relative stability by increasing the fluorine ratio where the capacity can be optimized by different surface group combinations. All results indicate that the AFT framework has the advantages of screening functional MXenes with a huge structure space from smaller and imbalanced data sets.

2.
Neurosurgery ; 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38619238

RESUMEN

BACKGROUND AND OBJECTIVES: Venous hypertensive myelopathy (VHM), mainly induced by the spinal dural arteriovenous fistula, is a congestive spinal cord injury that currently has no appropriate animal model available in preclinical research. METHODS: Sprague Dawley rats (280-320 g) were used. The rats were divided into 3 groups: (1) Group 1, which underwent renal artery-dorsal spinal venous bypass (AVB group); (2) Group 2, which underwent renal artery-dorsal spinal venous bypass and drainage vein stenosis (AVB/VS group); and (3) Control group, with T13 dorsal vein ligation. The success of the model was assessed using Doppler ultrasound and 7.0-T magnetic resonance imaging. Transmission electron microscopy, histochemistry, proteomics, and western blot analysis were used to evaluate ultrastructural, pathological, and molecular features in the spinal cord and cerebrospinal fluid (CSF). RESULTS: The success rate of the arteriovenous bypass was 100% at 5 days and 83% at 2 weeks. The locomotor assessment showed decreased lower extremity strength in the AVB/VS group (P = .0067), whereas unremarkable changes were found in the AVB and Control groups. Histochemical staining suggested a 2-fold expansion of the dorsal spinal vein in the AVB/VS group, which was lower than that in the AVB group (P < .05); however, the former displayed greater myelin and neuronal damage (P < .05) and slight dilatation of the central canal (P > .05). Proteomics analysis revealed that the complement and coagulation cascade pathways were upregulated in the CSF of AVB/VS rats, whereas the C3 level was elevated both in the CSF and bilateral spinal cord. Furthermore, overexpression of C3, ITGB2, and CD9 in the spinal cord was confirmed by immunoblotting. CONCLUSION: These findings suggest that the AVB/VS model can effectively mimic the clinical and molecular characteristics of VHM. Furthermore, they suggest that impaired deep intramedullary venous drainage is the key reason for the VHM.

3.
ACS Appl Mater Interfaces ; 16(17): 22580-22592, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38634565

RESUMEN

The application of high-performance rubber nanocomposites has attracted wide attention, but its development is limited by the imbalance of interface and network effects caused by fillers. Herein, an ultrastrong polymer nanocomposite is successfully designed by introducing a superhydrophobic and mesoporous silica aerogel (HSA) as the filler to poly(methyl vinyl phenyl) siloxane (PVMQ), which increased the PVMQ elongation at break (∼690.1%) by ∼9.3 times and the strength at break (∼6.6 MPa) by ∼24.3 times. Furthermore, HSA/PVMQ with a high dynamic storage modulus (G'0) of ∼12.2 MPa and high Payne effect (ΔG') of ∼9.4 MPa is simultaneously achieved, which is equivalent to 2-3 times that of commercial fumed silica reinforced PVMQ. The superior performance is attributed to the filler-rubber interfacial interaction and the robust filler-rubber entanglement network which is observed by scanning electron microscopy. When the HSA-PVMQ entanglement network is subjected to external stress, both the HSA and bound-PVMQ chains are synergistically involved in resisting structural evolution, resulting in the maximized energy dissipation and deformation resistance through the desorption of the polymer chain and the slip/interpenetrating of the exchange hydrogen bond pairs. Hence, highly aggregated nanoporous silica aerogels may soon be widely used in the application of reinforced silicone rubber or other polymers shortly.

4.
Angew Chem Int Ed Engl ; 63(15): e202400539, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38332434

RESUMEN

Sodium-ion batteries (SIBs) are recognized as promising energy storage devices. However, they suffer from rapid capacity decay at ultra-low temperatures due to high Na+ desolvation energy barrier and unstable solid electrolyte interphase (SEI). Herein, a weakly solvating electrolyte (WSE) with decreased ion-dipole interactions is designed for stable sodium storage in hard carbon (HC) anode at ultra-low temperatures. 2-methyltetrahydrofuran with low solvating power is incorporated into tetrahydrofuran to regulate the interactions between Na+ and solvents. The reduced Na+-dipole interactions facilitate more anionic coordination in the first solvation sheath, which consistently maintains anion-enhanced solvation structures from room to low temperatures to promote inorganic-rich SEI formation. These enable WSE with a low freezing point of -83.3 °C and faster Na+ desolvation kinetics. The HC anode thus affords reversible capacities of 243.2 and 205.4 mAh g-1 at 50 mA g-1 at -40 and -60 °C, respectively, and the full cell of HC||Na3V2(PO4)3 yields an extended lifespan over 250 cycles with high capacity retention of ~100 % at -40 °C. This work sheds new lights on the ion-dipole regulation for ultra-low temperature SIBs.

5.
Appl Spectrosc ; 78(5): 538-550, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38409815

RESUMEN

Four-wave mixing techniques, such as coherent anti-Stokes Raman spectroscopy (CARS), laser-induced grating spectroscopy (LIGS), and degenerate four-wave mixing (DFWM), have been widely used in combustion diagnostics due to their advantages of high signal-to-noise ratio (S/N), coherent signal, and spatial resolution. In this work, a nano-second pulsed laser is utilized to generate mid-infrared (near 3 µm) pump beams, exciting the rovibrational transitions of nascent water in flames. Combined LIGS and DFWM measurements are demonstrated in premixed laminar CH4/O2/N2 flames with equivalence ratios from 0.6 to 1.5, to achieve precise thermometry in a wide range of flame conditions. The flame temperatures were also measured by thermocouple as a reference, and the results from LIGS and DFWM align well with the trends shown in the thermocouple measurements. In fuel-lean flames, where the mass-to-specific-heat ratio variation is minimal, LIGS provides temperature data with a precision better than 16 K (0.8%). In fuel-rich flames, where the increased H2 concentration in the flame introduces uncertainty in gas constants thus affecting the accuracy of LIGS thermometry, DFWM is instead employed for temperature measurement since it is less sensitive to the gas composition within the measured volume. The high-precision LIGS temperatures in lean flames serve as temperature reference during the DFWM calibration of the degree of saturation, and a precision better than 90 K (4.5%) is achieved for DFWM thermometry. In addition to temperature, a theoretical model is employed to fit LIGS signal time waveforms, extracting the local speed of sound and thermal diffusivity with precisions better than 0.5% and 1.3%, respectively. These high-precision measurements contribute additional data for flame research and simulation calculations. This way, the combined use of DFWM and LIGS proves the potential for accurate thermometry and diagnostics of other thermodynamic parameters across a wide range of flame conditions.

6.
Artículo en Inglés | MEDLINE | ID: mdl-38305350

RESUMEN

BACKGROUND AND OBJECTIVES: Intraorbital arteriovenous fistulas (AVFs) are an extremely rare subtype of intracranial fistula with ophthalmic symptoms similar to cavernous sinus dural AVFs or carotid cavernous fistulas but worse visual outcomes. Here, we present a case series and thorough systematic review on intraorbital AVFs to demonstrate treatment modalities and address this rare type of AVF. METHODS: We conducted a retrospective study at a single center, in which we identified all cases of intraorbital AVFs that occurred between 2002 and 2022. We collected and analyzed data on demographics, fistula characteristics, treatment methods, clinical outcomes, and fistula closure. In addition, we conducted a systematic review of intraorbital AVFs. RESULTS: Seven cases in our center and 41 cases of intraorbital AVFs reported in the 35 articles were identified. At our center, transarterial embolization (TAE) (42.9%) alone resulted in immediate complete occlusion in 3 cases. Transvenous embolization (14.3%) resulted in one case of immediate complete occlusion. In 2 cases, surgery (28.6%) resulted in immediate complete occlusion. In one case, conservative treatment (14.3%) was used, and the fistula was eventually spontaneously occluded. Immediate complete occlusion rate was 85.7%. One blindness occurred (14.3%). In the literature reported, 3 cases (60%) of retinal artery occlusion were reported when performing TAE via the ophthalmic artery. Two fistulas recurred as reported. In 33 (80.5%) patients, the fistula was finally completely occluded. CONCLUSION: TAE via the ophthalmic artery carries a high risk of blindness and a low cure rate. Transvenous techniques such as conventional transvenous routes, surgical exposure, or direct puncture of the drainage vein have been used as the first line of treatment for intraorbital AVFs.

8.
Acta Neurochir (Wien) ; 166(1): 96, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38383924

RESUMEN

BACKGROUND: Isolated sinus dural arteriovenous fistulas (DAVFs) constitute a rare and distinctive subtype of DAVF, typically found in small case numbers or case reports. The optimal treatment for this DAVF type remains unclear. OBJECTIVE: This study aims to further detail the treatment outcomes of isolated sinus DAVFs in a sizable cohort from a single center. METHODS: A retrospective study was undertaken on a consecutive series of patients with isolated sinus DAVFs treated at a single institution from 2002 to 2022. The article delineates the clinical presentation, angiographic features, treatment strategy, clinical and angiographic outcomes, and complications. RESULTS: The cohort consisted of 31 males and 13 females, with an average age of 52.0 ± 15.5 years (range, 16-83). The success rate for trans-arterial embolization (TAE) was 97.3% (36/37). Transvenous embolization (TVE) with the reopening technique was successful in 3 of 4 patients (75.0%). Two open burr-hole TVE cases (66.7%, 2/3) and one surgery (100%) resulted in immediate complete closure of the fistula. Immediate complete occlusion was achieved in 93.2% (41/44) of cases. There was one major complication (2.3%, 1/44) and two fistulas recurred (9.5%, 2/21). CONCLUSIONS: The majority of isolated sinus DAVFs can be effectively treated with TAE using Onyx. TVE and surgery serve as alternative techniques when arterial access is deemed inappropriate or when complete occlusion cannot be attained with TAE. Complete embolization of isolated sinus DAVFs by TAE can typically be achieved without delay.


Asunto(s)
Malformaciones Vasculares del Sistema Nervioso Central , Embolización Terapéutica , Masculino , Femenino , Humanos , Adulto , Persona de Mediana Edad , Anciano , Estudios Retrospectivos , Resultado del Tratamiento , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico por imagen , Malformaciones Vasculares del Sistema Nervioso Central/cirugía , Procedimientos Quirúrgicos Vasculares , Angiografía , Embolización Terapéutica/efectos adversos
9.
J Ethnopharmacol ; 324: 117771, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38242218

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Melodinus axillaris W.T.Wang has been widely used as an important medicine in China. In the folk of China, its whole plant has been used for fractures, rheumatic heart disease, testitis, hernia, abdominal pain, and dyspepsia, etc. Despite its extensive use, there is a shortage of literature investigating the specific bioactive compounds and underlying mechanisms responsible for their anti-inflammatory effects. This knowledge gap serves as the primary impetus for conducting this study, which aims to shed light on the previously unexplored therapeutic potential of M. axillaris. AIM OF THE STUDY: This study aims to investigate the material basis and potential mechanism of anti-inflammatory activity of M. axillaris. MATERIALS AND METHODS: Compounds were isolated from the 95% ethanol extract of M. axillaris using a systematic phytochemical method. The structures were established by extensive spectroscopic analysis, including 1D and 2D NMR, HR-ESI-MS, ECD calculation, and DP4+ analysis. The anti-inflammatory activities of ethanol extract and compounds from M. axillaris were tested by an inflammation model of LPS-stimulated RAW264.7 cells in vitro. Western blot analysis was employed to evaluate the expressions of COX-2, iNOS, and NF-κB signaling pathways, aiming to elucidate the underlying mechanisms. RESULTS: Eleven undescribed monoterpenoid indole alkaloids (MIAs), axillines A-K (1-11), along with thirteen known analogs were isolated from M. axillaris. Compound 1 was the first representative of vincadine alkaloid with unprecedented 6/5/9/6/6 skeletons. Compounds 1-11 and ethanol extract showed significant anti-inflammatory effects in vitro. Among them, compound 2 had the best activity of inhibiting NO release (IC50 = 3.7 ± 0.9 µM). Additionally, subsequent Western blot analysis revealed that 2 could significantly inhibit the up-regulation of NF-κB signaling pathways, iNOS, and COX-2 in LPS-stimulated RAW264.7 cells, thereby demonstrating its anti-inflammatory activity. CONCLUSION: This study provides support for the traditional use of M. axillaris in terms of its anti-inflammatory properties and highlights the potential of MIAs as promising candidates for further development as anti-inflammatory drugs.


Asunto(s)
FN-kappa B , Alcaloides de Triptamina Secologanina , Ratones , Animales , FN-kappa B/metabolismo , Alcaloides de Triptamina Secologanina/farmacología , Ciclooxigenasa 2/metabolismo , Lipopolisacáridos/farmacología , Transducción de Señal , Antiinflamatorios/farmacología , Células RAW 264.7 , Extractos Vegetales/farmacología , Etanol/farmacología
10.
Neurosurg Rev ; 47(1): 46, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38221539

RESUMEN

Non-cavernous sinus (CS) dural arteriovenous fistulas (DAVFs) involving the sphenoid bone are rare entities that are easily confused with one another due to the complex structure and high variability of the venous system around the middle cranial fossa. We present a large retrospective study on middle cranial fossa non-CS DAVFs and review the literature on DAVF treatment in this location as well as relative anatomy. 15 patients had DAVFs involving the lesser sphenoid wing and 11 patients had DAVFs involving the greater sphenoid wing. Six patients presented with intracranial hemorrhage or subarachnoid hemorrhage (23.1%, 6/26). The most common symptoms were eye symptoms (38.5%, 10/26). Nineteen patients were treated with trans-arterial embolization (TAE) using liquid embolic agents and two patients were treated with transvenous embolization (TVE) using Onyx or in combination with coils. Surgical disconnection of the drainage veins was performed in five patients, with three cases experiencing unsuccessful TAE. Anatomic cure was achieved in 92.3% of the patients (24/26). Twelve patients had DSA and clinical follow-up from 3 to 27 months. There was one recurrence (8.3%) of the fistula in the patient two months after the initial complete occlusion. The majority of patients can be cured endovascularly. Laterocavernous sinus DAVFs may not be embolized by transvenous approach via the cavernous sinus because there is often no connection between them in most patients. A small percentage of patients may require surgical ligation to be cured.


Asunto(s)
Malformaciones Vasculares del Sistema Nervioso Central , Embolización Terapéutica , Humanos , Fosa Craneal Media/cirugía , Estudios Retrospectivos , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico por imagen , Malformaciones Vasculares del Sistema Nervioso Central/cirugía , Procedimientos Quirúrgicos Vasculares , Resultado del Tratamiento
11.
Sci Total Environ ; 919: 170465, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38290681

RESUMEN

Individual biological water treatment techniques often prove ineffective in removing accumulated high concentrations of nitrogen and phosphorus in the late stages of biofloc aquaculture. To address this issue, we integrated a previously developed autotrophic denitrification and nitrification integrated constructed wetland (ADNI-CW) with a microalgal membrane photobioreactor (MPBR). Under high nitrogen and phosphorus pollution loads in the influent, the standalone ADNI-CW system achieved removal rates of only 24.17 % ± 2.82 % for total nitrogen (TN) and 25.30 % ± 2.59 % for total phosphorus (TP). The optimal conditions for TN and TP degradation and microalgal biomass production in the Chlorella MPBR, determined using response surface methodology, were an inoculum OD680 of 0.394, light intensity of 161.583 µmol/m2/s, and photoperiod of 16.302 h light:7.698 h dark. Under the optimal operating conditions, the integrated ADNI-CW-MPBR system achieved remarkable TN and TP removal rates of 92.63 % ± 2.8 % and 77.46 % ± 8.41 %, respectively, and a substantial microalgal biomass yield of 54.58 ± 6.8 mg/L/day. This accomplishment signifies the successful achievement of efficient nitrogen and phosphorus removal from high-pollution-load marine aquaculture wastewater along with the acquisition of valuable microalgal biomass. A preliminary investigation of the microbial community composition and algal-bacterial interactions in different operational stages of the MPBR system revealed that unclassified_d__Bacteria, Chlorophyta, and Planctomycetes were predominant phyla. The collaborative relationships between bacteria and Chlorella surpassed competition, ensuring highly efficient nitrogen and phosphorus removal in the MPBR system. This study laid the foundation for the green and sustainable development of the aquaculture industry.


Asunto(s)
Enfermedad de Alzheimer , Chlorella , Microalgas , Aguas Residuales , Chlorella/metabolismo , Microalgas/metabolismo , Fotobiorreactores/microbiología , Humedales , Nitrógeno/análisis , Fósforo/metabolismo , Biomasa , Acuicultura
12.
Stroke Vasc Neurol ; 9(1): 18-29, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-37236656

RESUMEN

BACKGROUND: Craniocervical junction (CCJ) arteriovenous fistulas (AVFs) are rare. The current treatment strategies for AVFs with different angioarchitecture need to be clarified. The present study aimed to analyse the correlation between angioarchitecture and clinical characteristics, share our experience in treating this disease and identify risk factors associated with subarachnoid haemorrhage (SAH) and poor outcomes. METHODS: A total of 198 consecutive patients with CCJ AVFs from our neurosurgical centre were retrospectively reviewed. The patients were grouped according to their clinical manifestations, and their baseline clinical characteristics, angioarchitecture, treatment strategies and outcomes were summarised. RESULTS: The patients' median age was 56 years (IQR 47-62 years). The majority of patients were men with 166 (83.8%) patients. The most common clinical manifestation was SAH (52.0%), followed by venous hypertensive myelopathy (VHM) (45.5%). The most common CCJ AVFs type was dural AVF, with 132 (63.5%) fistulas. The most frequent fistula location was C-1 (68.7%) and dural branch of vertebral artery (70.2%) was the most involved arterial feeders for fistulas. The most common direction of venous drainage was descending intradural drainage (40.9%), followed by ascending intradural drainage (36.5%). Microsurgery was the most common treatment strategy applied for 151 (76.3%) patients, 15 (7.6%) patients were treated with interventional embolisation only, and 27 (13.6%) received both interventional embolisation and microsurgical treatment. The learning curve for microsurgery only was analysed by cumulative summation method, and the turning point was the 70th case, and blood loss in post-group was lower than that in pre-group (p=0.034). At the last follow-up, there were 155 (78.3%) patients with favourable outcomes (modified Rankin Scale(mRS)<3). Age≥56 (OR 2.038, 95% CI 1.039 to 3.998, p=0.038), VHM as the clinical manifestation (OR 4.102, 95% CI 2.108 to 7.982, p<0.001) and pretreatment mRS≥3 (OR 3.127, 95% CI 1.617 to 6.047, p<0.001) were significantly associated with poor outcomes. CONCLUSION: The arterial feeders and direction of the venous drainage were important factors in the clinical presentations. The location of fistula and drainage vein was essential for choosing different treatment strategies. Older age, VHM onset and poor pretreatment functional status predicted poor outcomes.


Asunto(s)
Fístula Arteriovenosa , Embolización Terapéutica , Hemorragia Subaracnoidea , Masculino , Humanos , Femenino , Persona de Mediana Edad , Estudios de Cohortes , Estudios Retrospectivos , Drenaje , Embolización Terapéutica/efectos adversos
14.
World Neurosurg ; 184: 3-4, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38159605

RESUMEN

Isolated sinus dural arteriovenous fistulas (DAVFs) involve a dural sinus with occlusion on both sides of the diseased sinus segment. Because of venous drainage refluxing from the isolated sinus into the cortical veins, all isolated sinus DAVFs are Borden type III or Cognard type Ⅲ/Ⅳ. Venous drainage typically involves temporo-occipital cortical veins or the superior petrosal sinus and tributaries of the petrosal vein. However, drainage veins involving the perimedullary venous system are extremely rare. Here, we present a case of Cognard type V isolated sinus DAVF successfully treated with balloon catheter and Onyx.


Asunto(s)
Seno Cavernoso , Malformaciones Vasculares del Sistema Nervioso Central , Venas Cerebrales , Embolización Terapéutica , Humanos , Angiografía Cerebral , Venas Cerebrales/diagnóstico por imagen , Venas Cerebrales/cirugía , Malformaciones Vasculares del Sistema Nervioso Central/complicaciones , Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico por imagen , Malformaciones Vasculares del Sistema Nervioso Central/cirugía , Drenaje
15.
Acta Neurol Belg ; 2023 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-37924471

RESUMEN

PURPOSE: The cavernous sinus (CS) region is a common region of dural arteriovenous fistula (DAVF). Over time, treatment strategies are gradually changing. In this study, we present our center's experience in managing CS-DAVF over the past 20 years. METHODS: Medical records of patients diagnosed with CS-DAVF between 2002 and 2021 were collected for analysis. Patients meeting the predefined inclusion and exclusion criteria were included. This study summarized and analyzed their clinical characteristics, CS-DAVF angioarchitecture, treatment strategies, and outcomes. RESULTS: A total of 141 patients (mean age 55 years, 46 males) were included in this study. Ocular/orbital symptoms were the most frequently reported initial symptoms, with 84 (59.6%) patients experiencing these symptoms first. Presentation with ocular/orbital symptoms as the first symptom was associated with thrombosis of the inferior petrosal sinus (p = 0.032). Presentation with headache/dizziness and tinnitus/intracranial murmur as the first symptom was associated with sphenoparietal sinus/superficial middle cerebral vein drainage (p = 0.011). Among the patients, 131 (92.9%) patients received endovascular treatment, with 114 (87.0%) undergoing transvenous embolization. Onyx (92.4%) and coil (74.8%) were the most used embolic materials. 17 (13.0%) of the patients who received endovascular treatment suffered intraoperative or postoperative complications, and 11 (64.7%) patients fully recovered within 6 months after discharge. CONCLUSION: Ocular/orbital symptoms were the most common first symptom of CS-DAVF. The mode of venous drainage played a significant role in determining the first symptoms. Transvenous embolization using Onyx or a combination of Onyx and coils was the primary treatment modality.

16.
Nat Commun ; 14(1): 6865, 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37891158

RESUMEN

Solution-processed polycrystalline perovskite film is promising for the next generation X-ray imaging. However, the spatial resolution of current perovskite X-ray panel detectors is far lower than the theoretical limit. Herein we find that the pixel level non-uniformity, also known as fixed pattern noise, is the chief culprit affecting the signal-to-noise ratio and reducing the resolution of perovskite detectors. We report a synergistic strategy of rheological engineering the perovskite suspensions to achieve X-ray flat panel detectors with pixel-level high uniformity and near-to-limit spatial resolution. Our approach includes the addition of methylammonium iodide and polyacrylonitrile to the perovskite suspension, to synergistically enhance the flowability and particle stability of the oversaturated solution. The obtained suspension perfectly suits for the blade-coating process, avoiding the uneven distribution of solutes and particles within perovskite films. The assembled perovskite panel detector exhibits greatly improved fixed pattern noise value (1.39%), high sensitivity (2.24 × 104 µC Gyair-1 cm-2), low detection limit (28.57 nGyair·s-1) as well as good working stability, close to the performance of single crystal detectors. Moreover, the detector achieves a near-to-limit resolution of 0.51 lp/pix.

17.
Artículo en Inglés | MEDLINE | ID: mdl-37889609

RESUMEN

Lithium-sulfur (Li-S) batteries hold great promise as next-generation high-energy storage devices owing to the high theoretical specific capacity of sulfur, but polysulfide shuttling and lithium dendrite growth remain key challenges limiting cycling life. In this work, we propose a polyacrylonitrile-derived asymmetric (PDA) separator to enhance Li-S battery performance by accelerating sulfur redox kinetics and guiding lithium plating and stripping. A PDA separator was constructed from two layers: the cathode-facing side consists of polyacrylonitrile nanofibers carbonized at 800 °C and doped with titanium nitride, which can achieve rapid polysulfide conversion via electrocatalysis to suppress their shuttling; the anode-facing side consists of polyacrylonitrile oxidized at 280 °C, on which the abundant electronegative groups guide uniform lithium ion plating and stripping. Li-S batteries assembled with the PDA separator exhibited enhanced rate performance, cycling stability, and sulfur utilization, retaining 426 mA h g-1 capacity at 1 C over 1000 cycles and 632 mA h g-1 at 4 C over 200 cycles. Attractively, the PDA separator showed high thermal stability, which could mitigate the risk of internal short circuits and thermal runaway. This work demonstrates an original path to addressing the most critical issues with Li-S batteries.

18.
Metabolites ; 13(9)2023 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-37755283

RESUMEN

Mulberry leaves contain α-glucosidase inhibitors, which have hypoglycemic effects and are considered functional foods. However, few reports have covered the effects of mulberry leaf components on normal gut microbiota and gut metabolites. Herein, gut microbiota analysis and NMR-based metabolomics were performed on the feces of mulberry leaf powder (MLP)-treated mice to determine the effects of long-term MLP consumption. Gut microbiota in the mouse were analyzed using 16S-rRNA gene sequencing, and no significant differences were revealed in the diversity and community structure of the gut microbiota in the C57BL/6 mice with or without MLP supplementation. Thirty-nine metabolites were identified via 1H-NMR analysis, and carbohydrates and amino acids were significantly (p < 0.01-0.05) altered upon MLP treatment. In the MLP-treated group, there was a marked increase and decrease in maltose and glucose concentrations, respectively, possibly due to the degradation inhibitory activity of oligosaccharides. After 5 weeks, all amino acid concentrations decreased. Furthermore, despite clear fluctuations in fecal saccharide concentrations, short-chain fatty acid production via intestinal bacterial metabolism was not strongly affected. This study provides the knowledge that MLP administration can alter the gut metabolites without affecting the normal gut microbiota, which is useful for considering MLP as a healthy food source.

19.
Front Microbiol ; 14: 1179414, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37675432

RESUMEN

Introduction: With the increasingly serious problem of antiviral drug resistance, drug repurposing offers a time-efficient and cost-effective way to find potential therapeutic agents for disease. Computational models have the ability to quickly predict potential reusable drug candidates to treat diseases. Methods: In this study, two matrix decomposition-based methods, i.e., Matrix Decomposition with Heterogeneous Graph Inference (MDHGI) and Bounded Nuclear Norm Regularization (BNNR), were integrated to predict anti-viral drugs. Moreover, global leave-one-out cross-validation (LOOCV), local LOOCV, and 5-fold cross-validation were implemented to evaluate the performance of the proposed model based on datasets of DrugVirus that consist of 933 known associations between 175 drugs and 95 viruses. Results: The results showed that the area under the receiver operating characteristics curve (AUC) of global LOOCV and local LOOCV are 0.9035 and 0.8786, respectively. The average AUC and the standard deviation of the 5-fold cross-validation for DrugVirus datasets are 0.8856 ± 0.0032. We further implemented cross-validation based on MDAD and aBiofilm, respectively, to evaluate the performance of the model. In particle, MDAD (aBiofilm) dataset contains 2,470 (2,884) known associations between 1,373 (1,470) drugs and 173 (140) microbes. In addition, two types of case studies were carried out further to verify the effectiveness of the model based on the DrugVirus and MDAD datasets. The results of the case studies supported the effectiveness of MHBVDA in identifying potential virus-drug associations as well as predicting potential drugs for new microbes.

20.
Int J Biol Macromol ; 253(Pt 3): 126634, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37678684

RESUMEN

To efficiently remove heavy metals from wastewater, designing an adsorbent with high adsorption capacity and ease of recovery is necessary. This paper presents a novel magnetic hybridized aerogel, Fe3O4/cellulose nanofiber/polyethyleneimine/thiol-modified montmorillonite (Fe3O4/CNF/PEI/SHMMT), and explores its adsorption performance and mechanism for Pb2+, Cu2+, and Cd2+ in aqueous solutions. The hybrid aerogel has a slit-like porous structure and numerous exposed active sites, which facilitates the uptake of metal ions by adsorption. Pb2+, Cu2+, and Cd2+ adsorption by the hybridized aerogel followed the second-order kinetics and the Langmuir isotherm model, the maximum adsorption of Pb2+, Cu2+, and Cd2+ at 25 °C, pH = 6, 800 mg/L was 429.18, 381.68 and 299.40 mg/g, respectively. The adsorption process was primarily attributed to monolayer chemical adsorption, a spontaneous heat-absorption reaction. FTIR, XPS and DFT studies confirmed that the adsorption mechanisms of Fe3O4/CNF/PEI/SHMMT on Pb2+, Cu2+, and Cd2+ were mainly chelation, coordination, and ion exchange. The lowest adsorption energy of Pb2+ on the hybrid aerogel was calculated to be -2.37 Ha by DFT, which indicates that the sample has higher adsorption affinity and preferential selectivity for Pb2+. After 5 cycles, the adsorption efficiency of the aerogel was still >85 %. The incorporation of Fe3O4 improved the mechanical properties of the aerogel. The Fe3O4/CNF/PEI/SHMMT has fast magnetic responsiveness, and it is easy to be separated and recovered after adsorption, which is a promising potential for the treatment of heavy metal ions.


Asunto(s)
Metales Pesados , Nanofibras , Contaminantes Químicos del Agua , Polietileneimina/química , Bentonita , Adsorción , Cadmio , Celulosa , Plomo , Metales Pesados/química , Iones/química , Fenómenos Magnéticos , Contaminantes Químicos del Agua/química , Cinética
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