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1.
Sci Rep ; 14(1): 1496, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233479

RESUMO

Plant image analysis is a significant tool for plant phenotyping. Image analysis has been used to assess plant trails, forecast plant growth, and offer geographical information about images. The area segmentation and counting of the leaf is a major component of plant phenotyping, which can be used to measure the growth of the plant. Therefore, this paper developed a convolutional neural network-based leaf counting model called LC-Net. The original plant image and segmented leaf parts are fed as input because the segmented leaf part provides additional information to the proposed LC-Net. The well-known SegNet model has been utilised to obtain segmented leaf parts because it outperforms four other popular Convolutional Neural Network (CNN) models, namely DeepLab V3+, Fast FCN with Pyramid Scene Parsing (PSP), U-Net, and Refine Net. The proposed LC-Net is compared to the other recent CNN-based leaf counting models over the combined Computer Vision Problems in Plant Phenotyping (CVPPP) and KOMATSUNA datasets. The subjective and numerical evaluations of the experimental results demonstrate the superiority of the LC-Net to other tested models.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Geografia , Desenvolvimento Vegetal , Folhas de Planta
2.
Cancer Chemother Pharmacol ; 93(4): 307-317, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37955741

RESUMO

Fedratinib is an oral Janus kinase 2-selective inhibitor for the treatment of adult patients with intermediate-2 or high-risk myelofibrosis; however, some patients have difficulty with oral dosing. This randomized, phase 1, open-label, 2-part crossover study evaluated the relative bioavailability, safety, tolerability, taste, and palatability of fedratinib resulting from various alternative oral administration methods in healthy adults. Participants could receive fedratinib 400 mg orally as intact capsules along with a nutritional supplement; as contents of capsules dispersed in a nutritional supplement, delivered via nasogastric tube; or as a divided dose of 200 mg orally twice daily as intact capsules with a nutritional supplement. Fifty-eight participants received treatment. Total exposure to fedratinib was similar after oral administration of intact capsules or when dispersed in a nutritional supplement (area under the plasma concentration-time curve from time 0 to the time of the last quantifiable concentration geometric mean ratio [AUC0-t GMR] [90% CI], 1.007 [0.929-1.092]). Total exposure to fedratinib was slightly reduced following nasogastric administration (AUC0-t GMR 0.850 [0.802-0.901]) and as a divided dose (AUC0-t GMR 0.836 [0.789-0.886]). No new safety signals were identified for fedratinib, and most participants found the taste and palatability acceptable when dispersed in a nutritional supplement. Overall, results suggest no clinically meaningful differences in total exposure to fedratinib between the tested oral administration methods. These findings may facilitate administration of fedratinib to patients who are intolerant of swallowing the capsule dosage form. (ClinicalTrials.gov: NCT05051553).


Assuntos
Disponibilidade Biológica , Adulto , Humanos , Estudos Cross-Over , Administração Oral , Área Sob a Curva
3.
Cureus ; 15(10): e47845, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38021802

RESUMO

Vulvar leiomyomas are rare benign tumors originating from smooth muscle cells of the vulvar tissue. We present the case of a 44-year-old female patient complaining of a painless vulval mass for 12 years, gradually increasing from 1x1 cm to 5x4 cm. Clinical assessment initially suggested a Bartholin cyst because of its non-tender and non-fluctuant nature. However, surgical intervention revealed an unexpected diagnosis of vulvar leiomyoma, measuring 5x5x4 cm. The patient underwent successful excision and repair under spinal anesthesia. This case underscores the significance of meticulous clinical evaluation and accurate histopathological examination in distinguishing vulvar masses. Accurate diagnosis guides appropriate management, and long-term follow-up prevents complications and recurrence. This report highlights the diagnostic challenges of rare vulvar lesions and the importance of a comprehensive approach to their evaluation and treatment.

4.
BMC Ophthalmol ; 23(1): 429, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872518

RESUMO

BACKGROUND: This study aimed to assess the prevalence and associated factors of diabetic retinopathy (DR) and vision threatening DR (VTDR) among people with diabetes screened using fundus photography in Nepal. METHODS: This is a retrospective study among people with diabetes presented for DR screening using fundus photography from 2013 to 2019. Detailed demographics, duration of diabetes, medical history, visual acuity, and grading of DR on fundus photography were analyzed. Fundus camera used in the study were;Topcon digital fundus camera 900 CXR and digital portable fundus cameras (Nidek-10 portable non-mydriatric fundus camera; Versacam & Trade & Alpha, France), and a Zeiss portable fundus camera (Zeiss Visucout 100). Macula centred and disc centred 45 degree two images were taken from each eye. Pupil were dilated in cases where there was media haze in un-dilated cases. DR was graded using early treatment diabetic retinopathy study criteria. The images were graded by fellowship trained retina specialist. DR prevalence included any DR changes in one or both eyes. RESULTS: Total of 25,196 patients with diabetes were enrolled. Mean age was 54.2 years with Standard Deviation (S.D):12.9 years, ranging from 6 years to 97 years. Type 1 and type 2 diabetes comprised of 451 people (1.79%) and 24,747 (98.21%) respectively. Overall, 1.8% of the images were un-gradable. DR prevalence was 19.3% (95% Confidence Interval (CI): 18.8 - 19.7%). DR prevalence in type 1 and type 2 diabetes was 15.5% (95% CI: 12.5 - 18.6%) and 19.3% (CI: 18.8 - 19.8%) respectively. Clinically significant macular edema (CSME) was found in 5.9% (95% CI: 5.6-6.2%) and VTDR in 7.9% (95% CI: 7.7-8.3%). In multivariate analysis, our study revealed strong evidence to suggest that there is meaningful association between DR and VTDR with duration of diabetes, diabetic foot, diabetic neuropathy, agriculture occupation, those under oral hypoglycaemic agents or insulin or both as compared to those under diet only, and presenting visual acuity > 0.3LogMAR. CONCLUSION: Prevalence and associated factors for DR and VTDR were similar to other DR screening programs in the region. Emphasis on wider coverage of DR screening could help for timely detection and treatment of STDR to avoid irreversible blindness.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Humanos , Pessoa de Meia-Idade , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Prevalência , Nepal/epidemiologia , Estudos Retrospectivos , Programas de Rastreamento/métodos , Fotografação
5.
Environ Monit Assess ; 195(11): 1362, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37872312

RESUMO

Silver-doped-titanium dioxide nanoparticles supported on Fuller's earth, prepared by the sol-gel method, were characterized with XRD, TGA, zeta potential, SEM, EDX, TEM, XPS, photoluminescence and UV-DRS measurements. The material, Ag-TiO2-Fuller's earth (AgTF), was tested for photocatalytic activity concerning the degradation of rhodamine B (RhB) and methylene blue (MB) in aqueous solution under visible light irradiation with pH, catalyst dosage, and dye concentration as the process variables. The degradation kinetics indicated pseudo-first-order kinetics with rate constant of (i) 0.55 min-1with 0.12 gL-1AgTF loading, 10-5 M MB at pH 9, and (ii) 0.53 min-1 with 0.08 g L-1 AgTF loading, 5 × 10-5 M RhB at pH 8. The methylene blue degradation was maximum (98.66%) for AgTF loading of 0.12 g L-1 while the maximum RhB degradation (96.34%) was attained with AgTF loading of 0.08 g L-1. With 5 × 10-6M MB concentration, the degradation achieved was 98% in 45 min and 100% in 60 min. One hundred per cent degradation of the dye, RhB (1 × 10-6 M) could be achieved in 30 min with 0.08 g L-1 AgTF at pH 8. The use of Fuller's earth, a cheap, abundant and large surface area support, increases the adsorbability of the dye on the catalyst surface and hence promotes the degradation. The catalyst could be removed easily from the reaction mixture and reused for up to five cycles without any significant decrease in activity. Scavengers such as triethanolamine (TEOA), p-benzoquinone (BQ) and isopropyl alcohol (IPA) were utilized to get some insight into the photocatalysis mechanism.


Assuntos
Azul de Metileno , Nanocompostos , Azul de Metileno/química , Prata , Monitoramento Ambiental , Luz , Titânio/química , Nanocompostos/química , Catálise
6.
J Med Chem ; 66(18): 13135-13147, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37724542

RESUMO

A series of dihydropyridinone (DHP) compounds was prepared and evaluated for MGAT2 activity. The efforts led to the identification of novel tetrazolones with potent MGAT2 inhibitory activity and favorable in vitro profiles. Further tests of select analogues in mouse models revealed significant reduction in food intake and body weight. Subsequent studies in MGAT2 knockout mice with the lead candidate 12 (BMS-986172) showed on-target- and mechanism-based pharmacology. Moreover, its favorable pharmacokinetic (PK) profile and the lack of species variability in the glucuronidation potential resulted in a greater confidence level in the projection of a low dose for achieving targeted efficacious exposures in humans. Consistent with these projections, PK data from a phase 1 trial confirmed that targeted efficacious exposures could be achieved at a low dose in humans, which supported compound 12 as our second and potentially superior development candidate for the treatment of various metabolic disorders.


Assuntos
Doenças Metabólicas , Piridonas , Animais , Humanos , Camundongos , Peso Corporal , Doenças Metabólicas/tratamento farmacológico , Piridonas/química , Piridonas/farmacologia , N-Acetilglucosaminiltransferases/antagonistas & inibidores
7.
Org Biomol Chem ; 21(38): 7724-7729, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37691553

RESUMO

A visible-light-driven organophotocatalyzed multi-component approach for carbothiolation of activated alkenes is demonstrated under environmentally benign and redox-neutral conditions, involving direct C(sp3)-H functionalization followed by electrophilic alkyl/arylthiolation. The three-component difunctionalization reaction is a complete transition-metal and peroxide-free process conducted under milder conditions. In this composite reaction, by employing bench-stable reagents, the formation of two new C(sp3)-C(sp3) and C(sp3)-S bonds is achieved for a wide variety of substrates, showcasing the excellent functional group tolerance and chemoselectivity of the methodology. Furthermore, the scalability and utilization of natural sunlight instead of artificial blue LEDs, along with the use of an inexpensive and easy-to-prepare pyrylium salt as an organo-photocatalyst, make this protocol greener and more energy efficient.

8.
Org Lett ; 25(28): 5308-5313, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37417829

RESUMO

Trifluoromethyl bicyclo[1.1.1]pentanes (BCPs) have attracted significant attention from the scientific community and pharmaceutical industries due to their advantageous physicochemical properties as arene bioisosteres. Initial photoredox perfluoroalkylation of [1.1.1]propellane triggers the tandem reaction to the perfluoroalkyl BCP radical followed by Giese addition to an in situ generated electron-deficient alkene by Knoevenagel condensation in a four-component fashion to form 1,3-functionalized BCPs. This strategy provides easy access to various 1,3-functionalized perfluoroalkyl BCP derivatives with the added advantage of nitrile group as a functional handle to diversified transformations. This methodology offers scalability and late-stage derivatization of drug molecules with high chemoselectivity.

9.
Arch Comput Methods Eng ; 30(5): 3379-3404, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37260909

RESUMO

Arithmetic Optimization Algorithm (AOA) is a recently developed population-based nature-inspired optimization algorithm (NIOA). AOA is designed under the inspiration of the distribution behavior of the main arithmetic operators in mathematics and hence, it also belongs to mathematics-inspired optimization algorithm (MIOA). MIOA is a powerful subset of NIOA and AOA is a proficient member of it. AOA is published in early 2021 and got a massive recognition from research fraternity due to its superior efficacy in different optimization fields. Therefore, this study presents an up-to-date survey on AOA, its variants, and applications.

10.
Arch Comput Methods Eng ; : 1-54, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37359743

RESUMO

There have been many algorithms created and introduced in the literature inspired by various events observable in nature, such as evolutionary phenomena, the actions of social creatures or agents, broad principles based on physical processes, the nature of chemical reactions, human behavior, superiority, and intelligence, intelligent behavior of plants, numerical techniques and mathematics programming procedure and its orientation. Nature-inspired metaheuristic algorithms have dominated the scientific literature and have become a widely used computing paradigm over the past two decades. Equilibrium Optimizer, popularly known as EO, is a population-based, nature-inspired meta-heuristics that belongs to the class of Physics based optimization algorithms, enthused by dynamic source and sink models with a physics foundation that are used to make educated guesses about equilibrium states. EO has achieved massive recognition, and there are quite a few changes made to existing EOs. This article gives a thorough review of EO and its variations. We started with 175 research articles published by several major publishers. Additionally, we discuss the strengths and weaknesses of the algorithms to help researchers find the variant that best suits their needs. The core optimization problems from numerous application areas using EO are also covered in the study, including image classification, scheduling problems, and many others. Lastly, this work recommends a few potential areas for EO research in the future.

11.
Arch Comput Methods Eng ; : 1-28, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37359742

RESUMO

Aquila Optimizer (AO) is a well-known nature-inspired optimization algorithm (NIOA) that was created in 2021 based on the prey grabbing behavior of Aquila. AO is a population-based NIOA that has demonstrated its effectiveness in the field of complex and nonlinear optimization in a short period of time. As a result, the purpose of this study is to provide an updated survey on the topic. This survey accurately reports on the designed enhanced AO variations and their applications. In order to properly assess AO, a rigorous comparison between AO and its peer NIOAs is conducted over mathematical benchmark functions. The experimental results show the AO provides competitive outcomes.

12.
Multimed Tools Appl ; : 1-63, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-37362658

RESUMO

Superpixel become increasingly popular in image segmentation field as it greatly helps image segmentation techniques to segment the region of interest accurately in noisy environment and also reduces the computation effort to a great extent. However, selection of proper superpixel generation techniques and superpixel image segmentation techniques play a very crucial role in the domain of different kinds of image segmentation. Clustering is a well-accepted image segmentation technique and proved their effective performance over various image segmentation field. Therefore, this study presents an up-to-date survey on the employment of superpixel image in combined with clustering techniques for the various image segmentation. The contribution of the survey has four parts namely (i) overview of superpixel image generation techniques, (ii) clustering techniques especially efficient partitional clustering techniques, their issues and overcoming strategies, (iii) Review of superpixel combined with clustering strategies exist in literature for various image segmentation, (iv) lastly, the comparative study among superpixel combined with partitional clustering techniques has been performed over oral pathology and leaf images to find out the efficacy of the combination of superpixel and partitional clustering approaches. Our evaluations and observation provide in-depth understanding of several superpixel generation strategies and how they apply to the partitional clustering method.

13.
Childs Nerv Syst ; 39(9): 2533-2536, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37209197

RESUMO

Vitamin B12 is inextricably associated with the development and maintenance of neuronal functions. It is classically associated with subacute combined degeneration and peripheral neuropathy; however, cranial neuropathy is uncommon. We observed the rarest neurological manifestation of B12 deficiency. A 12 months infant had history of lethargy, irritability, anorexia, paleness, vomiting, and neurodevelopmental delay for 2 months. He also developed inattention and altered sleep pattern. His mother noticed bilateral inward rotation of both eyes. On examination, the infant had bilateral lateral rectus palsy. The infant was found to have anemia (7.7g/dL) and severe B12 deficiency (74pg/mL). On MRI, there was cerebral atrophy, subdural hematoma (SDH) and wide cisternal spaces and sulci. On supplementation with cobalamin, he improved clinically though mild restriction of lateral gaze on the left side persists. Follow up MRI showed significant improvement in cerebral atrophy with resolution of SDH. To date, such clinical presentation of B12 deficiency has never been reported. The authors suggest B12 supplementation for at risk population esp at antenatal stage and lactating mothers in national programs. The treatment of this condition should be initiated early to prevent long term sequelae.


Assuntos
Doenças do Nervo Abducente , Deficiência de Vitamina B 12 , Masculino , Lactente , Humanos , Feminino , Gravidez , Deficiência de Vitamina B 12/complicações , Deficiência de Vitamina B 12/diagnóstico , Deficiência de Vitamina B 12/tratamento farmacológico , Lactação , Doenças do Nervo Abducente/complicações , Doenças do Nervo Abducente/tratamento farmacológico , Atrofia , Hematoma Subdural/complicações , Vitamina B 12/uso terapêutico
14.
Arch Comput Methods Eng ; 30(5): 3133-3172, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36855410

RESUMO

Marine Predators Algorithm (MPA) is the existing population-based meta-heuristic algorithms that falls under the category of Nature-Inspired Optimization Algorithm (NIOA) enthused by the foraging actions of the marine predators that principally pursues Levy or Brownian approach as its foraging strategy. Furthermore, it employs the optimal encounter rate stratagem involving both the predator as well as prey. Since its introduction by Faramarzi in the year 2020, MPA has gained enormous popularity and has been employed in numerous application areas ranging from Mathematical and Engineering Optimization problems to Fog Computing to Image Processing to Photovoltaic System to Wind-Solar Generation System for resolving continuous optimization problems. Such huge interest from the research fraternity or the massive recognition of MPA is due to several factors such as its simplicity, ease of application, realistic execution time, superior convergence acceleration rate, soaring effectiveness, its ability to unravel continuous, multi-objective and binary problems when compared with other renowned optimization algorithms existing in the literature. This paper offers a detailed summary of the Marine Predators Algorithm (MPA) and its variants. Furthermore, the applications of MPA in a number of spheres such as Image processing, classification, electrical power system, Photovoltaic models, structural damage detection, distribution networks, engineering applications, Task Scheduling, optimization problems etc., are illustrated. To conclude, the paper highlights and thereby advocates few of the potential future research directions for MPA.

15.
BMC Oral Health ; 23(1): 59, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36726123

RESUMO

BACKGROUND: Oral health problems are highly prevalent among school children in Nepal. Poor oral health condition may be influenced by various factors. However, little is known about the sociodemographic and awareness related factors on oral health problems among school children in Nepal. Therefore, this study aimed to assess the association of gender and knowledge on DMFT index among school children. METHODS: A cross-sectional study was conducted among school children of Grade Seven in 12 schools of Kaski district in Nepal. Schools were randomly selected from the urban and semi-urban areas in the district. Data were collected covering oral health knowledge, socio-demographic characteristics, oral health condition and practices. The factors of poor oral health condition and practices were examined using t-test, one-way ANOVA, and multiple linear regression. RESULTS: Of the total participants (n = 669), 54.9% were females and their mean DMFT score was 1.82 (SD = 1.07). Total decayed score was higher among those who did not have knowledge that fluoride prevents decay compared to those who had knowledge about it (Being aware of fluoride prevents decay: Mean = 1.21 (SD = 1.54) versus not being aware of that: mean = 2.13 (SD = 2.13); p = 0.029). Females were more likely to have higher DMFT scores compared to males (ß-coefficient = 0.43, 95% CI 0.13, 0.73, p = 0.005). In addition, higher knowledge score was negatively associated with higher DMFT score (ß-coefficient = - 0.09, 95% CI - 0.20, -0.01, p = 0.047). CONCLUSION: Being female students and those having lower level of knowledge on oral health attributed to higher DMFT index. Periodic dental check-up coupled with oral health education on regular brushing, use of fluoridated paste, tongue cleaning and care of gum diseases are recommended in schools.


Assuntos
Cárie Dentária , Saúde Bucal , Masculino , Humanos , Criança , Feminino , Estudos Transversais , Cárie Dentária/prevenção & controle , Nepal/epidemiologia , Fluoretos , Índice CPO , Prevalência
16.
Arch Comput Methods Eng ; 30(4): 2543-2578, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36624874

RESUMO

The intricacy of the real-world numerical optimization tribulations has full-fledged and diversely amplified necessitating proficient yet ingenious optimization algorithms. In the domain wherein the classical approaches fall short, the predicament resolving nature-inspired optimization algorithms (NIOA) tend to hit upon an excellent solution to unbendable optimization problems consuming sensible computation time. Nevertheless, in the last few years approaches anchored in nonlinear physics have been anticipated, announced, and flourished. The process based on non-linear physics modeled in the form of optimization algorithms and as a subset of NIOA, in countless cases, has successfully surpassed the existing optimization methods with their effectual exploration knack thus formulating utterly fresh search practices. Archimedes Optimization Algorithm (AOA) is one of the recent and most promising physics optimization algorithms that use meta-heuristics phenomenon to solve real-world problems by either maximizing or minimizing a variety of measurable variables such as performance, profit, and quality. In this paper, Archimedes Optimization Algorithm (AOA) has been discussed in great detail, and also its performance was examined for Multi-Level Thresholding (MLT) based image segmentation domain by considering t-entropy and Tsallis entropy as objective functions. The experimental results showed that among recent Physics Inspired Optimization Algorithms (PIOA), the Archimedes Optimization Algorithm (AOA) produces very promising outcomes with Tsallis entropy rather than with t-entropy in both color standard images and medical pathology images.

17.
J Phys Chem B ; 127(4): 996-1012, 2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36653942

RESUMO

PPh4Cl is an antagonistic salt that recently showed promise as a hydrotropic agent. Here, we give mechanistic insights into the PPh4Cl-assisted solubility of a dye molecule using molecular dynamics simulations. Our findings reveal that dye molecules aggregate into a cluster which leads to an accumulation of PPh4+ ions in its vicinity and subsequent exclusion of water molecules from the region. The structural organization is attributed to the preferential interaction of dye molecules and PPh4Cl. The origin of such preference arises from the difference in π-π and CH-π interaction among the pairs. The hydrodynamic radius of PPh4Cl indicates a low propensity for cluster formation, which enhances its hydrotropic behavior. The process of dye dissolution is thermodynamically favored and occurs through a cooperative mechanism. Our studies provide molecular insight into experimental observations crucial for the design of novel hydrotropes with enhanced solubilizing properties.

18.
J Ayurveda Integr Med ; 14(1): 100539, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35078695

RESUMO

STUDY BACKGROUND: In a pluralistic health care delivery model, it is important to assess whether the individual's health care choices are based upon evidences of efficacy and safety. Since the essence of medical pluralism lies in the fact that all such systems are equally accessible to a seeker, in such situation, it is highly relevant to check what defines such choices in real life. OBJECTIVE: To identify the factors influencing the health care choices in a subpopulation seeking Ayurveda health care in an Ayurvedic teaching hospital. MATERIALS AND METHOD: The study was an all-inclusive cross sectional survey, done on randomly selected out patients visiting an Ayurveda teaching hospital. The data was collected using a 21 items questionnaire refined through pilot testing from 7.9.2017 to 30.9.2017. RESULTS: The data of 289 respondents who have given their consent were included in statistical analysis. Out of 21 variables studied for their agreement or disagreement in the study population 8 were found to have a significant proportion in favour of agreement. Among these relative safety (Item 9); disease eradicating potential (Item 14); belief (Item 3) and indirect evidences of efficacy (Item 4) were found to have high significance (p < 0.001). CONCLUSION: Participants chose Ayurveda treatment due to its perceived safety and probability of helping in a particular clinical condition. Contrary to the common perception, enabling factors like availability, accessibility and affordability were given less importance by the participants in making health care choices related to Ayurveda.

19.
Evol Syst (Berl) ; : 1-46, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38625364

RESUMO

Nucleus segmentation is an imperative step in the qualitative study of imaging datasets, considered as an intricate task in histopathology image analysis. Segmenting a nucleus is an important part of diagnosing, staging, and grading cancer, but overlapping regions make it hard to separate and tell apart independent nuclei. Deep Learning is swiftly paving its way in the arena of nucleus segmentation, attracting quite a few researchers with its numerous published research articles indicating its efficacy in the field. This paper presents a systematic survey on nucleus segmentation using deep learning in the last five years (2017-2021), highlighting various segmentation models (U-Net, SCPP-Net, Sharp U-Net, and LiverNet) and exploring their similarities, strengths, datasets utilized, and unfolding research areas.

20.
Phys Chem Chem Phys ; 25(1): 326-340, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36477306

RESUMO

Grid-scale bulk energy storage solutions are needed to utilize the full potential of renewable energy technologies. Pseudocapacitive electrochemical energy storage can play a vital role in developing efficient energy storage solutions. The use of perovskites as anion intercalation-type pseudocapacitor electrodes has received significant attention in recent years. In this study, Sr-doped YMnO3i.e. Y1-xSrxMnO3-δ perovskite was prepared by the solid-state ceramic route and studied for electrochemical pseudocapacitance in aqueous KOH electrolyte. Microstructures, morphologies, and electrochemical properties of these materials were investigated through X-ray diffraction (XRD), scanning electron microscopy (SEM), cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance method. The formation of the mostly cubic phase, with 50% strontium doped YMnO3 (YSMO-50) provides an equivalent three-dimensional network and superior conductivity due to Mn3+-O2--Mn4+ hopping conduction. YSMO-50 exhibited low intrinsic resistance, 1.45 Ω cm-2, and the highest specific capacity, 259.83 F g-1 at a current density of 1 A g-1 in 2 M KOH aqueous electrolyte. Redox-mediated interconversion of oxide to hydroxide (M2+O2- + H2O + e- ↔ M+OH- + OH-) in aqueous media is shown to be the reason behind the high capacitance of YSMO-50. The excellent electrochemical performance of YSMOs was attributed to the reversible interconversion of oxide-ion into hydroxide ion coupled with surface redox reaction of Mn2+/Mn3+ and Mn3+/Mn4+ occurring during the charge-discharge process. The maximum energy density of 65.13 W h kg-1 was achieved at a power density of 0.45 kW kg-1 for an asymmetric mode, in which YSMO serves as a negative electrode and Activated carbon (AC) as a positive electrode in the PVA-KOH gel electrolyte. Our study reveals that the doping of low valence atom (Sr) at the A-site in perovskite manganites (YMnO3) may be an effective tool to enhance the pseudocapacitive performance of perovskite-based electrodes.

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