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1.
Cureus ; 16(5): e60339, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38751404

RESUMO

We present the case of an elderly female who presented to the emergency department with dizziness. She was found to have an acute chronic kidney injury complicated by a complete heart block (CHB). She received a transvenous pacemaker and was taken for hemodialysis (HD) with complete resolution of her heart block. The following day, she was noted to be symptomatic and bradycardic. A repeat electrocardiogram showed a recurrence of the CHB. She was taken again for HD which led to the resolution of her conduction abnormalities. Electrophysiology was consulted and she had a permanent pacemaker implanted prior to being discharged.

2.
Heliyon ; 10(6): e28157, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38524624

RESUMO

Automobile exhaust releases different types of pollutants that are at great risk to the air quality of the environment and incidental distress to the nature of roadside plants. Mimusops elengi L. is an evergreen medicinal tree cultivated along the roadside of Lahore City. This research aimed to investigate physiological, morphological and genomorphic characteristics of M. elengi under the influence of air pollution from vehicles. Healthy and mature leaves were collected from trees on Canal Bank and Mall roads of Lahore as the experimental sites and control sites were 20 km away from the experimental site. Different physiochemical, morphological, air pollution tolerance index (APTI) and molecular analysis for the detection of DNA damage were performed through comet assay. The results demonstrated the mean accumulated Cd, Pb, Cu and Ni heavy metal contents on the leaves were higher than the control plants (1.27, 3.22, 1.32 and 1.46 µg mg-1). APTI of trees was 9.04. Trees in these roads significantly (p < 0.01) had a lower leaf area, petiole length and leaf dry matter content in comparison to control site. Increased comet tail showed that DNA damage was higher for roadside trees than trees in the control area. For tolerance of air pollution, it necessary to check the APTI value for the M. elengi at the polluted road side of Lahore city. For long-term screening, the source and type of pollutants and consistent monitoring of various responses given by the trees should be known.

3.
Food Chem X ; 22: 101256, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38495457

RESUMO

Plant extracts have demonstrated the ability to act as coagulants for milk coagulation at an adequate concentration, wide temperatures and pH ranges. This research is focused on the use of different vegetative extracts such as Citrus aurnatium flower extract (CAFE), bromelain, fig latex, and melon extract as economical and beneficial coagulants in the development of plant-based cheddar-type cheese. The cheddar-type cheese samples were subjected to physicochemical analysis in comparison to controlled cheese samples made from acetic acid and rennet. The fat, moisture, protein, and salt contents remained the same over the storage period, but a slight decline was observed in pH. The Ferric reducing antioxidant power (FRAP) increased with the passage of the ripening period. The FTIR and Raman spectra showed exponential changes and qualitative estimates in the binding and vibrational structure of lipids and protein in plant-based cheeses. The higher FTIR and Raman spectra bands were observed in acid, rennet, bromelain, and CAFE due to their firm and strong texture of cheese while lower spectra were observed in cheese made from melon extract due to weak curdling and textural properties. These plant extracts are economical and easily available alternative sources for cheese production with higher protein and nutritional contents.

4.
Adv Sci (Weinh) ; 11(19): e2308205, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38482978

RESUMO

Developing cost-efficient trifunctional catalysts capable of facilitating hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR) activity is essential for the progression of energy devices. Engineering these catalysts to optimize their active sites and integrate them into a cohesive system presents a significant challenge. This study introduces a nanoflower (NFs)-like carbon-encapsulated FeNiPt nanoalloy catalyst (FeNiPt@C NFs), synthesized by substituting Co2+ ions with high-spin Fe2+ ions in Hofmann-type metal-organic framework, followed by carbonization and pickling processes. The FeNiPt@C NFs catalyst, characterized by its nitrogen-doped carbon-encapsulated metal alloy structure and phase-segregated FeNiPt alloy with slight surface oxidization, exhibits excellent trifunctional catalytic performance. This is evidenced by its activities in HER (-25 mV at 10 mA cm-2), ORR (half-wave potential of 0.93 V), and OER (294 mV at 10 mA cm-2), with the enhanced water oxidation activity attributed to the high-spin state of the Fe element. Consequently, the Zn-air battery and anion exchange membrane water electrolyzer assembled by FeNiPt@C NFs catalyst demonstrate remarkable power density (168 mW cm-2) and industrial-scale current density (698 mA cm-2 at 1.85 V), respectively. This innovative integration of multifunctional catalytic sites paves the way for the advancement of sustainable energy systems.

5.
Adv Mater ; : e2401448, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38518760

RESUMO

The amelioration of brilliantly effective electrocatalysts working at high current density for the oxygen evolution reaction (OER) is imperative for cost-efficient electrochemical hydrogen production. Yet, the kinetically sluggish and unstable catalysts remain elusive to large-scale hydrogen (H2) generation for industrial applications. Herein, a new strategy is demonstrated to significantly enhance the intrinsic activity of Ni1-xFex nanochain arrays through a trace proportion of heteroatom phosphorus doping that permits robust water splitting at an extremely large current density of 1000 and 2000 mA cm-2 for 760 h. The in situ formation of Ni2P and Ni5P4 on Ni1-xFex nanochain arrays surface and hierarchical geometry of the electrode significantly promote the reaction kinetics and OER activity. The OER electrode provides exceptionally low overpotentials of 222 and 327 mV at current densities of 10 and 2000 mA cm-2 in alkaline media, dramatically lower than benchmark IrO2 and is among the most active catalysts yet reported. Remarkably, the alkaline electrolyzer renders a low voltage of 1.75 V at a large current density of 1000 mA cm-2, indicating outperformed overall water splitting. The electrochemical fingerprints demonstrate vital progress toward large-scale H2 production for industrial water electrolysis.

6.
Nanoscale ; 16(8): 4189-4196, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38323830

RESUMO

Bi2O2Se has attracted intensive attention due to its potential in electronics, optoelectronics, and ferroelectric applications. Despite that, there have only been a handful of experimental studies based on ultrafast spectroscopy to elucidate the carrier dynamics in Bi2O2Se thin films. Besides, different groups have reported various ultrafast timescales and associated mechanisms across films of different thicknesses. A comprehensive understanding in relation to thickness and fluence is still lacking. In this work, we have systematically explored the thickness-dependent Raman spectroscopy and ultrafast carrier dynamics in chemical vapor deposition (CVD)-grown Bi2O2Se thin films on a mica substrate with thicknesses varying from 22.44 nm down to 4.62 nm in both low and high pump fluence regions. Combining the thickness dependence and fluence dependence of the slow decay time, we demonstrate a hidden photoinduced ferroelectric transition in the thinner (<8 nm) Bi2O2Se films below the material damage thresholds, influenced by substrate-induced compressive strain and far-from-equilibrium excitation. Moreover, this transition can be manifested at high electronic excitation densities. Our results deepen the understanding of the interplay between the ferroelectric phase and semiconducting characteristics of Bi2O2Se thin films, offering potential applications in optoelectronic devices that benefit from the ferroelectric transition.

7.
Small ; : e2311929, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38396229

RESUMO

The global pursuit of sustainable energy is focused on producing hydrogen through electrocatalysis driven by renewable energy. Recently, High entropy alloys (HEAs) have taken the spotlight in electrolysis due to their intriguing cocktail effect, broad design space, customizable electronic structure, and entropy stabilization effect. The tunability and complexity of HEAs allow a diverse range of active sites, optimizing adsorption strength and activity for electrochemical water splitting. This review comprehensively covers contemporary advancements in synthesis technique, design framework, and physio-chemical evaluation approaches for HEA-based electrocatalysts. Additionally, it explores design principles and strategies aimed at optimizing the catalytic activity, stability, and effectiveness of HEAs in hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and overall water splitting. Through an in-depth investigation of these aspects, the complexity inherent in constituent element interactions, reaction processes, and active sites associated with HEAs is aimed to unravel. Eventually, an outlook regarding challenges and impending difficulties and an outline of the future direction of HEA in electrocatalysis is provided. The thorough knowledge offered in this review will assist in formulating and designing catalysts based on HEAs for the next generation of electrochemistry-related applications.

8.
Sci Total Environ ; 919: 170696, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38340850

RESUMO

The rising global population and rapid industrialization have frequently resulted in a significant escalation in energy requirements. Hydrogen, renowned for its eco-friendly and renewable characteristics, has garnered substantial interest as a fuel alternative to address the energy needs currently fulfilled by fossil fuels. Embracing such energy substitutes holds pivotal importance in advancing environmental sustainability, aiding in the reduction of greenhouse gas emissions - the primary catalysts of global warming and climate fluctuations. This study elucidates recent trends in sewage sludge (SS)-derived hydrogen through diverse production pathways and critically evaluates the impact of varying parameters on hydrogen yield. Furthermore, a detailed analysis of the breakdown of the hydrogen generation process from SS is provided, along with an assessment of its economic dimensions. The review culminates by illuminating key obstacles in the adoption of this innovative technology, accompanied by practical recommendations to surmount these challenges. This comprehensive analysis is expected to attract considerable interest from stakeholders within the hydrogen production domain, fostering substantial engagement.

9.
Childs Nerv Syst ; 40(5): 1367-1375, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38240786

RESUMO

OBJECTIVE: Rathke cleft cysts (RCCs) are benign, epithelial-lined sellar lesions that arise from remnants of the craniopharyngeal duct. Due to their rarity in the pediatric population, data are limited regarding the natural history and optimal management of growing or symptomatic RCCs. We present our institutional experience with the surgical management of RCCs. METHODS: We performed a retrospective study of consecutive RCC patients ≤ 18 years old treated surgically at our institution between 2006 and 2022. RESULTS: Overall, 567 patients with a diagnosis of pituitary mass or cyst were identified. Of these, 31 had a histopathological diagnosis of RCC, 58% female and 42% male. The mean age was 13.2 ± 4.2 years. Presenting symptoms included headache (58%), visual changes (32%), and endocrinopathies or growth delay (26%); 13% were identified incidentally and subsequently demonstrated growth on serial imaging. Six percent presented with symptomatic intralesional hemorrhage. Surgical approach was transsphenoidal for 90% of patients and orbitozygomatic for 10%. Preoperative headaches resolved in 61% of patients and preoperative visual deficits improvement in 55% after surgery. New pituitary axis deficits were seen in 9.7% of patients. Only two complications occurred from a first-time surgery: one cerebrospinal fluid leak requiring lumbar drain placement, and one case of epistaxis requiring cauterization. No patients experienced new visual or neurological deficits. Patients were followed postoperatively with serial imaging at a mean follow-up was 62.9 ± 58.4 months. Recurrence requiring reoperation occurred in 32% of patients. Five-year progression-free survival was 47.9%. Except for one patient with multiple neurological deficits from a concurrent tectal glioma, all patients had a modified Rankin Scale score of 0 or 1 (good outcome) at last follow-up. CONCLUSION: Due to their secretory epithelium, pediatric RCCs may demonstrate rapid growth and can cause symptoms due to local mass effect. Surgical management of symptomatic or growing pediatric RCCs via cyst fenestration or partial resection of the cyst wall can be performed safely, with good neurologic outcomes. There is a nontrivial risk of endocrinologic injury, and long-term follow up is needed due to high recurrence rates.


Assuntos
Carcinoma de Células Renais , Cistos do Sistema Nervoso Central , Cistos , Neoplasias Renais , Humanos , Criança , Masculino , Feminino , Adolescente , Estudos Retrospectivos , Cistos do Sistema Nervoso Central/cirurgia
10.
Chest ; 165(5): 1111-1119, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38211699

RESUMO

BACKGROUND: Approximately one-third of acute ICU patients display atypical sleep patterns that cannot be interpreted by using standard EEG criteria for sleep. Atypical sleep patterns have been associated with poor weaning outcomes in acute ICUs. RESEARCH QUESTION: Do patients being weaned from prolonged mechanical ventilation experience atypical sleep EEG patterns, and are these patterns linked with weaning outcomes? STUDY DESIGN AND METHODS: EEG power spectral analysis during wakefulness and overnight polysomnogram were performed on alert, nondelirious patients at a long-term acute care facility. RESULTS: Forty-four patients had been ventilated for a median duration of 38 days at the time of the polysomnogram study. Eleven patients (25%) exhibited atypical sleep EEG. During wakefulness, relative EEG power spectral analysis revealed higher relative delta power in patients with atypical sleep than in patients with usual sleep (53% vs 41%; P < .001) and a higher slow-to-fast power ratio during wakefulness: 4.39 vs 2.17 (P < .001). Patients with atypical sleep displayed more subsyndromal delirium (36% vs 6%; P = .027) and less rapid eye movement sleep (4% vs 11% total sleep time; P < .02). Weaning failure was more common in the atypical sleep group than in the usual sleep group: 91% vs 45% (P = .013). INTERPRETATION: This study provides the first evidence that patients in a long-term acute care facility being weaned from prolonged ventilation exhibit atypical sleep EEG patterns that are associated with weaning failure. Patients with atypical sleep EEG patterns had higher rates of subsyndromal delirium and slowing of the wakeful EEG, suggesting that these two findings represent a biological signal for brain dysfunction.


Assuntos
Eletroencefalografia , Polissonografia , Desmame do Respirador , Humanos , Desmame do Respirador/métodos , Masculino , Feminino , Eletroencefalografia/métodos , Pessoa de Meia-Idade , Idoso , Respiração Artificial/métodos , Sono/fisiologia , Unidades de Terapia Intensiva , Vigília/fisiologia , Delírio/fisiopatologia , Delírio/etiologia , Delírio/diagnóstico , Fatores de Tempo
11.
Small ; 20(3): e2304594, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37691089

RESUMO

The development of efficient and low-cost catalysts for cathodic oxygen reduction reaction (ORR) in Zn-air battery (ZAB) is a key factor in reducing costs and achieving industrialization. Here, a novel segregated CoNiPt alloy embedded in N-doped porous carbon with a nanoflowers (NFs)-like hierarchy structure is synthesized through pyrolyzing Hofmann-type metal-organic frameworks (MOFs). The unique hierarchical NFs structure exposes more active sites and facilitates the transportation of reaction intermediates, thus accelerating the reaction kinetics. Impressively, the resulting 15% CoNiPt@C NFs catalyst exhibits outstanding alkaline ORR activity with a half-wave potential of 0.93 V, and its mass activity is 7.5 times higher than that of commercial Pt/C catalyst, surpassing state-of-the-art noble metal-based catalysts. Furthermore, the assembled CoNiPt@C+RuO2 ZAB demonstrates a maximum power density of 172 mW cm-2 , which is superior to that of commercial Pt/C+RuO2 ZAB. Experimental results reveal that the intrinsic ORR mass activity is attributed to the synergistic interaction between oxygen defects and pyrrolic/graphitic N species, which optimizes the adsorption energy of the intermediate species in the ORR process and greatly enhances catalytic activity. This work provides a practical and feasible strategy for synthesizing cost-effective alkaline ORR catalysts by optimizing the electronic structure of MOF-derived catalysts.

12.
Laryngoscope Investig Otolaryngol ; 8(6): 1579-1583, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38130264

RESUMO

Objectives: The current literature provides limited guidance on the management of positive margins (PMs) following transoral laser microsurgery (TLM) for glottic squamous cell carcinoma (SCC). Long-term data exploring the treatment of PMs with both initial observation and re-resection are limited. Our objective was to determine the optimal treatment for PM patients following TLM for glottic SCC. Methods: Clinical information on glottic SCC patients with PMs following treatment with TLM was prospectively collected at our institution from 2007 to 2018. We use a laryngeal template during the initial TLM where the area of resection is outlined for future reference. Data were compared with univariate analysis and survival plots were generated using the Kaplan-Meier method. Results: A total of 29 patients with PMs were treated with either re-resection (19 patients), close observation (6 patients), or adjuvant radiation alone (4 patients). Re-resection patients had SCC or severe dysplasia on initial margin pathology and 23% with early-stage disease had recurrence (T1-T2). Five (83%) patients who underwent close observation required re-resection based on clinical suspicion of recurrence (confirmed on final pathology), which was significantly different from the re-resection patients (p < .05). Close observation was therefore discontinued as a management of PMs. Four patients (21%) had no residual malignancy on re-resection specimens. Deep margins only accounted for 17% of all PMs. Disease-specific survival for all PM patients at 5 years was 82.4% (SE 9.6%, CI 53.4%-91.6%). Conclusions: Our long-term experience with treating early-stage glottic SCC with TLM supports re-resection as an appropriate management for cases of PMs. Level of Evidence: 4.

13.
Res Involv Engagem ; 9(1): 122, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38129935

RESUMO

As patient-advocacy, public policy and clinical researchers with special knowledge on Responsible Research Innovation (RRI) governance and the public health and psychology underlying patient engagement, we read with interest the comment contribution by Richards et al., "Reflections on patient engagement by patient partners: How it can go wrong" (Richards et al. in Res Involv Engagem 9:41, 2023. https://doi.org/10.1186/s40900-023-00454-13 ). As a way to help meet the "take-away actions for readers" included by the authors at the end of the article, we would like to further stimulate discussion with relevant stakeholder communities about the need to rethink the use of "expert patient". Based on our experience, the lack of a governance model engaging patients who are representative of the target patient community, as opposed to expert patients, is at the root of the tokenistic approach, the "patient partner as a checkmark statement" and the "lack of recognizing the vulnerability of patient partners", which results in "patient engagement going wrong". According to our experience, the Responsible Research Innovation (RRI) MULTI-ACT model has the potential to help meet these challenges.


In their article, Richards et al. (Res Involv Engagem 9:41, 2023. https://doi.org/10.1186/s40900-023-00454-13 ) reflect on the practices of patient engagement in research, highlighting not only the value and opportunity of including people suffering from a disease as coinvestigators in the research process but also the risks and errors that must be avoided in such a process. Along this line of discussion­and based on our experience of research, teaching and patient advocacy­we further reflect on the nature of the concept of "expert patient" in this paper. In particular, we argue for the importance of guaranteeing the wide inclusion of all the different kinds of "experiential knowledge" that patients may bring into the research project, and we question the risk of a poorly representative approach if only guided to select patients with acquired knowledge and expertise about the scientific research process itself. Based on our experience, the Responsible Research Innovation (RRI) governance models have the potential to help meet these challenges.

14.
Cereb Circ Cogn Behav ; 5: 100187, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37811523

RESUMO

Cerebral small vessel disease (SVD) is a major cause of cognitive impairment in older people. As secondary endpoints in a phase-2 randomised clinical trial, we tested the effects of single administration of a widely-used PDE5 inhibitor, tadalafil, on cognitive performance in older people with SVD. In a double-blinded, placebo-controlled, cross-over trial, participants received tadalafil (20 mg) and placebo on two visits ≥ 7 days apart (randomised to order of treatment). The Montreal Cognitive Assessment (MOCA) was administered at baseline, alongside a measure to estimate optimal intellectual ability (Test of Premorbid Function). Then, before and after treatment, a battery of neuropsychological tests was administered, assessing aspects of attention, information processing speed, working memory and executive function. Sixty-five participants were recruited and 55 completed the protocol (N = 55, age: 66.8 (8.6) years, range 52-87; 15/40 female/male). Median MOCA score was 26 (IQR: 23, 27], range 15-30). No significant treatment effects were seen in any of the neuropsychological tests. There was a trend towards improved performance on Digit Span Forward (treatment effect 0.37, C.I. 0.01, 0.72; P = 0.0521). We did not identify significant treatment effects of single-administration tadalafil on neuropsychological performance in older people with SVD. The trend observed on Digit Span Forward may help to inform future studies. Clinical trial registration: http://www.clinicaltrials.gov. Unique identifier: NCT00123456, https://eudract.ema.europa.eu. Unique identifier: 2015-001,235-20NCT00123456.

15.
Cureus ; 15(8): e44101, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37750152

RESUMO

Diarrhoea is a common presentation in acute emergency with potentially multifactorial causes. Hence, the chances of misdiagnosis can be high. Among these causes are listed diseases which are primarily inflammatory in nature. Presented here is a rare case of Behcet's colitis with valuable clinical lessons, in a patient who is known to have Behcet's disease and was admitted with acute onset bloody diarrhoea. This was a gastrointestinal manifestation of the patient's multisystemic inflammatory disorder as proven by investigations via computed tomography (CT) scan, sigmoidoscopy, and histology. He was treated with steroids and mesalazine, and later switched to infliximab and made a quick recovery.

16.
Cureus ; 15(8): e43694, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37724212

RESUMO

Chronic obstructive pulmonary disease (COPD) is a common and debilitating condition that often necessitates hospitalization for exacerbations. Since COPD exacerbations can cause significant morbidity and mortality, managing them is crucial for patient care. Effective management of COPD exacerbations is essential to prevent complications, as COPD exacerbations are associated with increased healthcare costs and decreased quality of life. This review aims to comprehensively discuss the management of COPD exacerbations, covering various pharmacologic and non-pharmacologic strategies. These include inhaled bronchodilators, systemic steroids, antibiotics, invasive and non-invasive ventilation, oxygen therapy, smoking cessation, immunization with pneumococcal vaccine, inhalers at discharge, pulmonary rehabilitation, long-term oxygen therapy (LTOT), ambulatory oxygen therapy, short-burst oxygen therapy, extracorporeal membrane oxygenation (ECMO), lung volume reduction surgery (LVRS), endobronchial procedures, and lung transplant. It is drawn upon various sources, including clinical studies, systemic reviews, and observational studies, to provide a comprehensive overview of current practices and identify areas for future research and innovation in managing COPD exacerbations. Addressing these areas of interest can improve patient outcomes and quality of life.

17.
Sci Technol Adv Mater ; 24(1): 2242262, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37614964

RESUMO

Developing efficient electrode materials is a key towards high power electrochemical energy storage devices. Two-dimensional (2D) MXene shows excellent conductivity and electrochemical performance among other materials. However, the restacking of MXene layers may degrade their specific capacity and cycling performance. Considering this challenge, here we have designed a composite made of 2D MXene nanosheets and lanthanum oxide (La2O3) nanoparticles to overcome the limitations. The bifunctionality of La2O3 nanoparticles prevents the restacking of MXene layers and enhances the electrochemical properties of the electrode due to its good Faradic characteristics. The specific capacitance of the La2O3/MXene composite electrode is 366 F/g at 1 A/g, which is 4.5 and 3 times higher than those of the individual La2O3 and MXene. The composite electrode displays a capacitance retention of 96% after 1,000 cycles, which is due to synergistic effects between the two components and indicates the potential of La2O3/MXene composite for supercapacitors.

18.
Med Biol Eng Comput ; 61(10): 2677-2697, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37428300

RESUMO

Computed tomography (CT) scan provides first-hand knowledge to doctors to identify an ailment. Deep neural networks help enhance image understanding through segmentation and labeling. In this work, we implement two variants of Pix2Pix generative adversarial networks (GANs) with varying complexities of generator and discriminator networks for plane invariant segmentation of CT scan images and subsequently propose an effective generative adversarial network with a suitably weighted binary cross-entropy loss function followed by image processing layer necessary for getting high-quality output segmentation. Our conditional GAN is powered by a unique set of an encoder-decoder network that coupled with the image processing layer produces enhanced segmentation. The network can be extended to the complete set of Hounsfield units and can also be implemented on smartphones. Furthermore, we also demonstrate effects on accuracy, F-1 score, and Jaccard index by using the conditional GAN networks on the spine vertebrae dataset, thus achieving an average of 86.28 % accuracy, 90.5 % Jaccard index score, and 89.9 % F-1 score in predicting segmented maps for validation input images. In addition, an overall lifting of accuracy, F-1 score, and Jaccard index graph for validation images with better continuity has also been highlighted.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Entropia , Processamento de Imagem Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos
19.
Molecules ; 28(12)2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37375258

RESUMO

Photocatalytic CO2 reduction to valuable hydrocarbon solar fuel is of great significance but still challenging. Strong CO2 enrichment ability and easily adjustable structures make metal-organic frameworks (MOFs) potential photocatalysts for CO2 conversion. Even though pure MOFs have the potential for photoreduction of CO2, the efficiency is still quite low due to rapid photogenerated electron-hole recombination and other drawbacks. In this work, graphene quantum dots (GQDs) were in situ encapsulated into highly stable MOFs via a solvothermal method for this challenging task. The GQDs@PCN-222 with encapsulated GQDs showed similar Powder X-ray Diffraction (PXRD) patterns to PCN-222, indicating the retained structure. The porous structure was also retained with a Brunauer-Emmett-Teller (BET) surface area of 2066 m2/g. After incorporation of GQDs, the shape of GQDs@PCN-222 particles remained, as revealed by the scanning electron microscope (SEM). As most of the GQDs were covered by thick PCN-222, it was hard to observe those GQDs using a transmission electron microscope (TEM) and a high-resolution transmission electron microscope (HRTEM) directly, the treatment of digested GQDs@PCN-222 particles by immersion in a 1 mM aqueous KOH solution can make the incorporated GQDs visible in TEM and HRTEM. The linker, deep purple porphyrins, make MOFs a highly visible light harvester up to 800 nm. The introduction of GQDs inside PCN-222 can effectively promote the spatial separation of the photogenerated electron-hole pairs during the photocatalytic process, which was proved by the transient photocurrent plot and photoluminescence emission spectra. Compared with pure PCN-222, the obtained GQDs@PCN-222 displayed dramatically enhanced CO production derived from CO2 photoreduction with 147.8 µmol/g/h in a 10 h period under visible light irradiation with triethanolamine (TEOA) as a sacrificial agent. This study demonstrated that the combination of GQDs and high light absorption MOFs provides a new platform for photocatalytic CO2 reduction.

20.
Adv Mater ; 35(33): e2302127, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37252818

RESUMO

The bioimpedances of tissues beyond the stratum corneum, which is the outermost layer of skin, contain crucial clinical information. Nevertheless, bioimpedance measurements of both the viable skin and the adipose tissue are not widely used, mainly because of the complex multilayered skin structure and the electrically insulating nature of the stratum corneum. Here, a theoretical framework is established for analyzing the impedances of multilayered tissues and, in particular, of skin. Then, strategies are determined for the system-level design of electrodes and electronics, which minimize 4-wire (or tetrapolar) measurement errors even in the presence of a top insulating tissue, thus enabling non-invasive characterizations of tissues beyond the stratum corneum. As an example, non-invasive measurements of bioimpedances of living tissues are demonstrated in the presence of parasitic impedances which are much (e.g., up to 350 times) higher than the bioimpedances of the living tissues beyond the stratum corneum, independently on extreme variations of the barrier (tape stripping) or of the skin-electrode contact impedances (sweat). The results can advance the development of bioimpedance systems for the characterization of viable skin and adipose tissues in several applications, including transdermal drug delivery and the assessment of skin cancer, obesity, dehydration, type 2 diabetes mellitus, cardiovascular risk, and multipotent adult stem cells.


Assuntos
Diabetes Mellitus Tipo 2 , Neoplasias Cutâneas , Adulto , Humanos , Pele , Epiderme , Administração Cutânea
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