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1.
Phys Imaging Radiat Oncol ; 29: 100530, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38275002

RESUMO

Background and purpose: Radiomic features from MRI and PET are an emerging tool with potential to improve prostate cancer outcomes. However, feature robustness due to image segmentation variations is currently unknown. Therefore, this study aimed to evaluate the robustness of radiomic features with segmentation variations and their impact on predicting biochemical recurrence (BCR). Materials and methods: Multi-scanner, pre-radiation therapy imaging from 142 patients with localised prostate cancer was used. Imaging included T2-weighted (T2), apparent diffusion coefficient (ADC) MRI, and prostate-specific membrane antigen (PSMA)-PET. The prostate gland and intraprostatic tumours were manually and automatically segmented, and differences were quantified using Dice Coefficient (DC). Radiomic features including shape, first-order, and texture features were extracted for each segmentation from original and filtered images. Intraclass Correlation Coefficient (ICC) and Mean Absolute Percentage Difference (MAPD) were used to assess feature robustness. Random forest (RF) models were developed for each segmentation using robust features to predict BCR. Results: Prostate gland segmentations were more consistent (mean DC = 0.78) than tumour segmentations (mean DC = 0.46). 112 (3.6 %) radiomic features demonstrated 'excellent' robustness (ICC > 0.9 and MAPD < 1 %), and 480 features (15.4 %) demonstrated 'good' robustness (ICC > 0.75 and MAPD < 5 %). PET imaging provided more features with excellent robustness than T2 and ADC. RF models showed strong predictive power for BCR with a mean area under the receiver-operator-characteristics curve (AUC) of 0.89 (range 0.85-0.93). Conclusion: When using radiomic features for predictive modelling, segmentation variability should be considered. To develop BCR predictive models, radiomic features from the entire prostate gland are preferable over tumour segmentation-based features.

2.
Adv Mater ; 36(16): e2312960, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38146892

RESUMO

Processable covalent organic framework membranes (COFM) are emerging as potential semiconducting materials for device applications. Nevertheless, the fabrication of crystalline and free-standing 3D COFMs is challenging. In this work, a unique time and solvent-efficient triple-layer-dual interfacial (TLDI) approach for the simultaneous synthesis of two 3D COFMs from a single system is developed. Besides, for the first time, the optical conductivity of these free-standing 3D COFMs is analyzed using terahertz (THz) spectroscopy in transmission mode. Interestingly, these membranes show excellent transmittance at THz frequencies with very high intrinsic THz conductivities. The evaluated scattering time and plasma frequency of the free carriers of the COFMs are highly promising for future applications in optoelectronic devices in THz frequencies.

3.
Heliyon ; 9(9): e19479, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809530

RESUMO

The COVID-19 pandemic has slowed down economic growth and disrupted labor markets throughout the world, including Bangladesh. A significant proportion of people lost income sources in the formal and informal sectors, triggering them to return to villages, and the transition introduces us to the new phenomenon known as "reverse migration". This study explores and synthesizes the COVID-19 induced changing patterns of migration and returnees' coping strategies based on their level of preparedness as well as resource mobilization. A mixed-method research approach was applied to conduct the research. The study area was Rangpur (Pirganj, Taraganj, and Kaunia). For collecting primary data, semi-structured survey questionnaires were used and conducted 84 field survey data, 12 Focus Group Discussions (FGDs), 6 In-Depth Interviews (IDIs), 2 Key Informant Interviews (KIIs), and participant observations. Descriptive statistics and thematic analysis with the assistance of NVivo software were used to present the findings of this study. The findings of the study revealed that the COVID-19 pandemic fueled informal job holders' returning to their homeland due to a low level of preparedness and mobilized resources. The study found that most respondents were in severe level unemployment. As a result, a lack of physical assets, they could not start new income-generating ventures and encountered food insecurity due to unexpected price hikes. The alarming result indicates that internal reverse migration is gendered, and the adverse impact is more prevalent among female migrants rather than male migrants. Along with the governmental organizations, the highlights of this study would be essential for non-governmental organizations and development practitioners.

4.
Environ Sci Pollut Res Int ; 30(51): 110764-110778, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37794227

RESUMO

In this article, binary oxide ZnCo2O4 nanoparticles (NPs) have been developed on reduced graphene oxide surface by simple reflux condensation method. The physicochemical characteristics of the synthesized nanocomposite were computed using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and UV-Visible spectroscopy. The average size of ZnCo2O4 NPs is found to be about 9 nm. The synthesized nanocomposite was found to be an extremely efficient catalyst for reduction of 4-nitrophenol (4-NP) to produce 4-aminophenol (4-AP) and it is exhibited that about 98% 4-nitrophenol can be reduced in only 20 min. The nanocomposite behaves as supercapacitor due to possessing the specific capacitance value up to 609 F/g and excellent capacitance retention over 1000 cycles. The Brunauer-Emmett-Teller (BET) surface area analysis has been conducted to evaluate surface area and pore size of the synthesized material. The antimicrobial activity of this nanocomposite was performed against bacterial strains of Escherichia coli (E. coli), Bacillus subtilis (B. subtilis), and Staphylococcus aureus (S. aureus) and it is noticed to be a good antimicrobial agent against different bacterial strains.


Assuntos
Escherichia coli , Nanocompostos , Staphylococcus aureus , Nanocompostos/química
5.
Exp Cell Res ; 429(2): 113671, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37276998

RESUMO

Primary cilia (PCs) that are present in most human cells and perform sensory function or signal transduction are lost in many solid tumors. Previously, we identified VDAC1, best known to regulate mitochondrial bioenergetics, to negatively regulate ciliogenesis. Here, we show that downregulation of VDAC1 in pancreatic cancer-derived Panc1 and glioblastoma-derived U-87MG cells significantly increased ciliation. Those PCs were significantly longer than the control cells. Such increased ciliation possibly inhibited cell cycle, which contributed to reduced proliferation of these cells. VDAC1-depletion also led to longer PCs in quiescent RPE1 cells. Therefore, serum-induced PC disassembly was slower in VDAC1-depleted RPE1 cells. Overall, this study reiterates the importance of VDAC1 in modulating tumorigenesis, due to its novel role in regulating PC disassembly and cilia length.


Assuntos
Cílios , Glioblastoma , Humanos , Cílios/metabolismo , Transdução de Sinais , Mitocôndrias/metabolismo , Divisão Celular , Glioblastoma/genética , Glioblastoma/metabolismo , Canal de Ânion 1 Dependente de Voltagem/genética , Canal de Ânion 1 Dependente de Voltagem/metabolismo
6.
RSC Adv ; 12(51): 33365-33402, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36425193

RESUMO

Indanones are prominent motifs found in number of natural products and pharmaceuticals. Particularly, 1-indanones occupy important niche in chemical landscape due to their easy accessibility and versatile reactivity. In the past few years, significant advancement has been achieved regarding cyclization of 1-indanone core. The present review focuses on recent (2016-2022) annulations involving 1-indanones for the construction of fused- and spirocyclic frameworks. In this context, new strategies for synthesis of various carbocyclic as well as heterocyclic skeletons are demonstrated. Mechanistic aspects of representative reactions are illustrated for better understanding of reaction pathways. A large number of transformations described in this review offer stereoselective formation of desired polycyclic compounds. Importantly, several reactions provide biologically relevant compounds and natural products, such as, plecarpenene/plecarpenone, swinhoeisterol A, cephanolides A-D, diptoindonesin G and atlanticone C.

7.
Health Mark Q ; 38(2-3): 188-204, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34632967

RESUMO

The current study is conceptualized to assess the perception of the general population towards health insurance providers and the policy features, to segment them based on their attitudes. The mixed-method design is used in this study. One fifty health insurance users response were analyzed. The data analysis technique includes focus group discussion, henry garret ranking method, factor analysis and cluster analysis. This study concludes that health insurance providers needs to devise insurance policies incorporating the features of home health, telemedicine and income protection features. The existing users should be offered customization option due to covid-19 to prevent customer switch.


Assuntos
COVID-19 , Comportamento do Consumidor , Humanos , Seguro Saúde , SARS-CoV-2
8.
J Affect Disord ; 294: 170-179, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34298222

RESUMO

BACKGROUND: COVID-19 outbreak has drawn out institutions to closure with several challenges for university students of undergraduate level in Dhaka city including an emergency shift from traditional learning to online learning, which associated digital divide, left several arguments in response to technological inefficiency, pedagogic inefficiency of teachers, inappropriate study environment and so on. Previous literature shows that the COVID-19 is imposing a threat to mental health all over the nation since its spread. This study intended to evaluate the emerging reasons for psychological distress among university students of undergraduate level in Dhaka, also assess the execution methods, barriers of online learning, and lastly, the attitudes of students regarding online learning throughout the pandemic. METHODS: A mixed methodology was used to conduct the research. Primary data has been collected using simple purposive sampling on 180 undergraduate students, 9 interviews were taken including 6 in-depth interviews of different university undergraduates from Dhaka city and also 3 (KIIs) from specialists of pedagogy and medical anthropology, and a high official from Bangladesh Telecommunication Regulatory Commission (BTRC). RESULTS: Based on the Kessler K-10 distress scale, the study found that the prevalence of no psychological distress (16.67%) followed by mild (40%), moderate (30.56%), and severe psychological distress (12.78%). CONCLUSION: The results concluded considering several reasons for mild to severe psychological distress. The findings suggest some recommendations to accumulate the process of online learning effectively and also strategies to regulate the preferred mode of learning in future.


Assuntos
COVID-19 , Exclusão Digital , Educação a Distância , Bangladesh/epidemiologia , Humanos , Pandemias , SARS-CoV-2 , Estudantes
9.
Zootaxa ; 4890(3): zootaxa.4890.3.3, 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33311117

RESUMO

Epibiosis is a common phenomenon, found in different taxa of aquatic animals. This relationship could occur as hyperepibiosis, when a basibiont being also an epibiont, providing a stable substrate for the hypersymbiont. Here we reported a ciliate-bryozoan-crustacean hyperepibiosis in Mandovi River mouth, Goa, West coast of India. We provided descriptions and characterization of the crab Atergatis sp., serving as basibiont for the bryozoan Triticella pedicellata (Alder, 1857), in turn colonized with (hyperepibionts) the ciliates Paracineta saifulae (Mereschkowsky, 1877) and Cothurnia ceramicola Kahl, 1933. Paracineta saifulae and Cothurnia ceramicola are reported here for first time from the Indian Ocean.


Assuntos
Braquiúros , Briozoários , Cilióforos , Animais , Índia
10.
Protein Pept Lett ; 16(9): 1063-73, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19508219

RESUMO

Single crystal X-ray diffraction studies and solvent dependent (1)H NMR titrations reveal that a set of four tetrapeptides with general formula Boc-Xx(1)-Aib(2)-Yy(3)-Zz(4)-OMe, where Xx, Yy and Zz are coded L-amino acids, adopt equivalent conformations that can be described as overlapping double turn conformations stabilized by two 4-->1 intramolecular hydrogen bonds between Yy(3)-NH and Boc C=O and Zz(4)-NH and Xx(1)C=O. In the crystalline state, the double turn structures are packed in head-to-tail fashion through intermolecular hydrogen bonds to create supramolecular helical structures. Field emission scanning electron microscopic (FE-SEM) images of the tetrapeptides in the solid state reveal that they can form flat tape-like structures. The results establish that synthetic Aib containing supramolecular helices can form highly ordered self-aggregated amyloid plaque like human amylin.


Assuntos
Ácidos Aminoisobutíricos/química , Oligopeptídeos/química , Amiloide/química , Cristalização , Cristalografia por Raios X , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Microscopia Eletrônica de Varredura , Ressonância Magnética Nuclear Biomolecular , Conformação Proteica , Estrutura Secundária de Proteína
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