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Ribosomally synthesized post-translationally modified peptides (RiPPs) are a novel category of bioactive natural products (NPs). Streptomyces bacteria are a potential source of many bioactive NPs. Limited opportunities are available to characterize all the bioactive NP gene clusters. In this study, 410 sequences of Streptomyces were analyzed for RiPPs through genome mining using the National Center for Biotechnology Information (NCBI), by combining BAGEL and anti-SMASH. A total of 4098 RiPPs were found; including both classified (lanthipeptide, RiPP-like, bacteriocin, LAPs, lassopeptide, thiopeptides) and nonclassified RiPPs. Soil was identified as a rich habitat for RiPPs. These data may offer alternative future remedies for various health issues.
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BACKGROUND: Cyclin-dependent kinase 9 (CDK9) stimulates oncogenic transcriptional pathways in cancer and CDK9 inhibitors have emerged as promising therapeutic candidates. METHODS: The activity of an orally bioavailable CDK9 inhibitor, CDKI-73, was evaluated in prostate cancer cell lines, a xenograft mouse model, and patient-derived tumor explants and organoids. Expression of CDK9 was evaluated in clinical specimens by mining public datasets and immunohistochemistry. Effects of CDKI-73 on prostate cancer cells were determined by cell-based assays, molecular profiling and transcriptomic/epigenomic approaches. RESULTS: CDKI-73 inhibited proliferation and enhanced cell death in diverse in vitro and in vivo models of androgen receptor (AR)-driven and AR-independent models. Mechanistically, CDKI-73-mediated inhibition of RNA polymerase II serine 2 phosphorylation resulted in reduced expression of BCL-2 anti-apoptotic factors and transcriptional defects. Transcriptomic and epigenomic approaches revealed that CDKI-73 suppressed signaling pathways regulated by AR, MYC, and BRD4, key drivers of dysregulated transcription in prostate cancer, and reprogrammed cancer-associated super-enhancers. These latter findings prompted the evaluation of CDKI-73 with the BRD4 inhibitor AZD5153, a combination that was synergistic in patient-derived organoids and in vivo. CONCLUSION: Our work demonstrates that CDK9 inhibition disrupts multiple oncogenic pathways and positions CDKI-73 as a promising therapeutic agent for prostate cancer, particularly aggressive, therapy-resistant subtypes.
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Coronavirus has long been considered a global epidemic. It caused the deaths of nearly 7.01 million individuals and caused an economic downturn. The number of verified coronavirus cases is increasing daily, putting the whole human race at danger and putting strain on medical experts to eradicate the disease as rapidly as possible. As a consequence, it is vital to predict the upcoming coronavirus positive patients in order to plan actions in the future. Furthermore, it has been discovered all across the globe that asymptomatic coronavirus patients play a significant part in the disease's transmission. This prompted us to incorporate similar examples in order to accurately forecast trends. A typical strategy for analysing the rate of pandemic infection is to use time-series forecasting technique. This would assist us in developing better decision support systems. To anticipate COVID-19 active cases for a few countries, we recommended a hybrid model utilizing a fuzzy time series (FTS) model mixed with a non-linear growth model. The coronavirus positive case outbreak has been evaluated for Italy, Brazil, India, Germany, Pakistan, and Myanmar through June 5, 2020 in phase-1, and January 15, 2022 in phase-2, and forecasts active cases for the next 26 and 14 days respectively. The proposed framework fitting effect outperforms individual logistic growth and the fuzzy time series techniques, with R-scores of 0.9992 in phase-1 and 0.9784 in phase-2. The proposed model provided in this article may be utilised to comprehend a country's epidemic pattern and assist the government in developing better effective interventions.
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COVID-19 , Previsões , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , Previsões/métodos , SARS-CoV-2/isolamento & purificação , Lógica Fuzzy , Modelos Logísticos , PandemiasRESUMO
This study explores the factors influencing users' behavioral intentions, attitudes and actual adoption of quick response (QR) mobile payment in the least developed country (LDC) of Bangladesh, by extending the original unified theory of acceptance and use of technology (UTAUT) model. The study conducts a mixed-methods investigation by combining the partial least squares (PLS) and focus group discussion (FGD) methods to empirically evaluate the research model and cross-validate the findings. Using purposive sampling, data were gathered from 412 respondents, followed by 10 respondents who took part in the FGD, who all met the sample criteria. The study findings indicate that performance expectancy, effort expectancy, and social influence significantly positively influence users' behavioral intention, while self-concept, perceived self-efficacy, and habit substantially influence their attitudes towards using QR mobile payments. The findings also confirm a positive effect of users' attitudes toward using QR mobile payment on both behavioral intention and actual use, and a positive effect of behavioral intention on the actual use of QR mobile payments. These findings offer several important theoretical and managerial implications.
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Genetically engineered (GE) crops have the potential to contribute to agricultural sustainability, food security, and nutritional enrichment. However, these crops cannot be released for commercial cultivation without undergoing environmental risk assessments (ERA), thus biosafety evaluation. ERA assessments are performed comparatively with their natural non-GE counterparts. As Bangladesh is progressing with GE potato research, the present study aims to collect baseline information on non-GE potato cultivation with an emphasis on current agronomic practices focusing on fertilizer management and farmers' knowledge base. The survey had three parts, including information on the farmers, information on potato cultivation practices, especially fertilizer use, and lastly, the farmer's view on GE potato. From 2020 to 2021, data were collected through interviews with experienced growers in four potato-growing regions, the Central and Mid-East, North-West, Mid-West, and South-East regions (n = 1757) of the country. The study revealed that farmers of all regions used more than the recommended amounts of fertilizer; for instance, 67.1% more nitrogen fertilizer was applied as an extra dose during potato cultivation in Munshiganj (Central and Mid-East) than in the Dinajpur region (North-West). This overuse of nitrogen fertilizer can enhance plant vigor but makes the plants more susceptible to insect attraction and allows pests easier access to the plants. As a result, the excess dose of nitrogen fertilizer in Munshiganj may act as a catalyst to increase the probability of late blight. The findings also showed that 73.6% of farmers observed unexpected flowering in certain potato cultivars, which corresponded to the higher application of phosphate and potassium fertilizers aimed at late blight control. Furthermore, this study reported infestations of Solanaceous weeds, specifically Solanum torvum and Physalis heterophylla, in potato fields. Finally, our findings demonstrated that more than 68.7% of the potato growers intend to adopt disease-resistant GE potato as that may reduce the need for excess fertilizer use and thus reduce cultivation costs.
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Selecting an appropriate anode material (AM) has been considered to be a crucial initial step in advancing high-performance batteries. Within this piece of research, we examine the suitability of the BC6NA monolayer (referred to as BC6NAML) as an AM by first-principles calculations. The BC6NAML exhibits metallic behavior consistently, even with varying concentrations of Na atoms, making it an ideal choice for battery usages. Our findings revealed that the theoretical storage capacity for Na-adhered BC6NAML was 406.36 mAhg-1, surpassing graphite, TiO2, BC6NA, and numerous other 2D materials. The BC6NAML also demonstrates a diffusion barrier of 0.39 eV and favorable diffusivity of Na-ions. Although the open-circuit voltage (OCV) of BC6NAML was temperate and lower compared to the OCV of other AMs like TiO2, our results suggested that it is possible to utilize BC6NAML as one of the encouraging host materials for sodium-ion batteries (SIBs). Consequently, this investigation into the potential anodic application of BC6NAML proves valuable for future experimental studies into sodium storage for SIBs.
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Potentially toxic elements (PTEs) in sediment can be highly hazardous to the environment and public health. This study aimed to assess the human and ecological risks of PTEs in sediments around a pharmaceutical industry in Ilorin, Nigeria. Physicochemical parameters and the concentrations of lead (Pb), chromium (Cr), cadmium (Cd), cobalt (Co), arsenic (As), and nickel (Ni) were analyzed in sediment samples collected from seven locations in the wet and dry seasons. Standard two-dimensional principal component analysis (PCA) and risk assessments were also conducted. The concentrations of Pb, Co, Ni, Cr, Cd, and As in the sediments ranged from 0.001 to 0.031 mg/kg, 0-0.005 mg/kg, 0.005-0.012 mg/kg, 0.001-0.014 mg/kg, 0.005-0.024 mg/kg, and 0.001-0.012 mg/kg, respectively. The mean concentrations of the total PTEs content were found in decreasing order of concentration: Pb > Cd > Ni > Cr > As > Co. PCA showed that some of the PTEs were highly concentrated in samples obtained at other locations as well as at the discharge point. The Hazard Index was mostly <1 across locations, indicating little to no probable non-cancerous effect. However, the incremental lifetime cancer risk for arsenic and nickel was high and required attention. The ecological risk assessment showed that lead and arsenic were the major PTEs pollutants in all locations. The study identifies PTEs profiles in sediments and emphasises the necessity of continual monitoring and action to stop long-term negative impacts on the local environment and public health.
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Effective removal of chemically toxic selenium oxoanions at high-capacity and trace levels from contaminated water remains a challenge in current scientific pursuits. Here, we report the functionalization of the MgAl layered double hydroxide with molybdenum-oxysulfide (MoO2S2) anion, referred to as LDH-MoO2S2, and its potential to sequester SeVIO42- and SeIVO32- from aqueous solution. LDH-MoO2S2 nanosheets were synthesized by an ion exchange method in solution. Synchrotron X-ray pair distribution function (PDF) and extended X-ray absorption fine structure (EXAFS) revealed an unexpected transformation of the MoO2S22- to Mo2O2S62- like species during the intercalation process. LDH-MoO2S2 is remarkably efficient in removing SeO42- and SeO32- ions from the ppm to trace level (≤10 ppb), with distribution constant (Kd) ranging from 104 to 105 mL/g. This material showed exceptionally high sorption capacities of 237 and 358 mg/g for SeO42- and SeO32-, respectively. Furthermore, LDH-MoO2S2 demonstrates substantial affinity and efficiency to remove SeO32-/SeO42- even in the presence of competitive ions from contaminated water. Hence, the removal of selenium (VI/IV) oxoanions collectively occurs through reductive precipitation and ion exchange mechanisms. This work provides significant insights into the chemical structure of the MoO2S2 anion into LDH and emphasizes its exceptional potential for high-capacity selenium removal and positioning it as a premier sorbent for selenium oxoanions.
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The Global Navigation Satellite System (GNSS) software-defined receivers offer greater flexibility, cost-effectiveness, customization, and integration capabilities compared to traditional hardware-based receivers, making them essential for a wide range of applications. The continuous evolution of GNSS research and the availability of new features require these software-defined receivers to upgrade continuously to facilitate the latest requirements. The Finnish Geospatial Research Institute (FGI) has been supporting the GNSS research community with its open-source implementations, such as a MATLAB-based GNSS software-defined receiver `FGI-GSRx' and a Python-based implementation `FGI-OSNMA' for utilizing Galileo's Open Service Navigation Message Authentication (OSNMA). In this context, longer datasets are crucial for GNSS software-defined receivers to support adaptation, optimization, and facilitate testing to investigate and develop future-proof receiver capabilities. In this paper, we present an updated version of FGI-GSRx, namely, FGI-GSRx-v2.0.0, which is also available as an open-source resource for the research community. FGI-GSRx-v2.0.0 offers improved performance as compared to its previous version, especially for the execution of long datasets. This is carried out by optimizing the receiver's functionality and offering a newly added parallel processing feature to ensure faster capabilities to process the raw GNSS data. This paper also presents an analysis of some key design aspects of previous and current versions of FGI-GSRx for a better insight into the receiver's functionalities. The results show that FGI-GSRx-v2.0.0 offers about a 40% run time execution improvement over FGI-GSRx-v1.0.0 in the case of the sequential processing mode and about a 59% improvement in the case of the parallel processing mode, with 17 GNSS satellites from GPS and Galileo. In addition, an attempt is made to execute v2.0.0 with MATLAB's own parallel computing toolbox. A detailed performance comparison reveals an improvement of about 43% in execution time over the v2.0.0 parallel processing mode for the same GNSS scenario.
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Questing ticks carry various tick-borne pathogens (TBPs) that are responsible for causing tick-borne diseases (TBDs) in humans and animals around the globe, especially in the tropics and sub-tropics. Information on the distribution of ticks and TBPs in a specific geography is crucial for the formulation of mitigation measures against TBDs. Therefore, this study aimed to survey the TBPs in the questing tick population in Bangladesh. A total of 2748 questing hard ticks were collected from the pastures in Sylhet, Bandarban, Sirajganj, Dhaka, and Mymensingh districts through the flagging method. After morphological identification, the ticks were grouped into 142 pools based on their species, sexes, life stages, and collection sites. The genomic DNA extracted from tick specimens was screened for 14 pathogens, namely Babesia bigemina (AMA-1), Babesia bovis (RAP-1), Babesia naoakii (AMA-1), Babesia ovis (18S rRNA), Theileria luwenshuni (18S rRNA), Theileria annulata (Tams-1), Theileria orientalis (MPSP), Anaplasma marginale (groEL), Anaplasma phagocytophilum (16S rRNA), Anaplasma bovis (16S rRNA), Anaplasma platys (16S rRNA), Ehrlichia spp. (16S rRNA), Rickettsia spp. (gltA), and Borrelia (Bo.) spp. (flagellin B) using genus and species-specific polymerase chain reaction (PCR) assays. The prevalence of the detected pathogens was calculated using the maximum likelihood method (MLE) with 95 % confidence interval (CI). Among 2748 ixodid ticks, 2332 (84.86 %) and 416 (15.14 %) were identified as Haemaphysalis bispinosa and Rhipicephalus microplus, respectively. Haemaphysalis bispinosa was found to carry all the seven detected pathogens, while larvae of R. microplus were found to carry only Bo. theileri. Among the TBPs, the highest detection rate was observed in A. bovis (20/142 pools, 0.81 %, CI: 0.51-1.20), followed by T. orientalis (19/142 pools, 0.72 %, CI: 0.44-1.09), T. luwenshuni (9/142 pools, 0.34 %, CI: 0.16-0.62), B. ovis (4/142 pools, 0.15 %, CI: 0.05 - 0.34) and Bo. theileri (4/142 pools, 0.15 %, CI: 0.05-0.34), Ehrlichia ewingii (3/142 pools, 0.11 %, CI: 0.03-0.29), and Babesia bigemina (1/142, 0.04 %, CI: 0.00 - 0.16). This study reports the existence of T. luwenshuni, E. ewingii, and Bo. theileri in Bangladesh for the first time. The novel findings of this study are the foremost documentation of transovarian transmission of B. bigemina and E. ewingii in H. bispinosa and also provide primary molecular evidence on the presence of E. ewingii and Bo. theileri in H. bispinosa. Therefore, this study may shed light on the circulating TBPs in ticks in the natural environment and thereby advocate awareness among physicians and veterinarians to control and prevent TBDs in Bangladesh.
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Babesia , Doenças Transmitidas por Carrapatos , Animais , Bangladesh/epidemiologia , Babesia/isolamento & purificação , Babesia/genética , Feminino , Masculino , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/parasitologia , Theileria/isolamento & purificação , Theileria/genética , Theileria/classificação , Ixodidae/microbiologia , Ixodidae/parasitologia , Anaplasma/isolamento & purificação , Anaplasma/genética , Ehrlichia/isolamento & purificação , Ehrlichia/genética , Carrapatos/microbiologia , Carrapatos/parasitologia , DNA Bacteriano/genética , HumanosRESUMO
Water constitutes an indispensable resource for global life but remains susceptible to pollution from diverse human activities. To mitigate this issue, researchers are committed to purifying water using a variety of materials to remove harmful chemicals, such as heavy metals. Layered double hydroxides (LDHs), with their intriguing, layered structure and chemical behavior, have attained substantial attention for their effectiveness in removing heavy metal cations and various inorganic oxoanions from water. To enhance the efficiency, considerable endeavors have focused on functionalizing LDHs with different chemical species. Intercalation with metal sulfides has proven to be particularly effective, facilitating heavy metal absorption through multiple mechanisms, including ion-exchange, reductive precipitation, and surface sorption. This review concentrates on the synthesis and performance of polysulfide (Sx, x = 2-5), Mo-S, and Sn-S anion intercalated LDHs for heavy metal cations and inorganic oxoanion sorption, along with their mechanisms. Furthermore, the discussion includes prospects for expanding the chemistry of metal sulfide intercalated LDHs, with existing challenges and future outlooks.
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This research focused on synthesizing a CdIn2Se4@Ch nanocomposite by doping CdIn2Se4 into chitosan using a photolysis assisted ultrasonic process. The aim was to enhance the photodegradation efficiency of ofloxacin and 2,4-dichlorophenoxyacetic acid under sunlight. The synthesized CdIn2Se4@Ch nanocomposite was investigated via different techniques, including XRD, XPS, FTIR, TEM, DSC, TGA, UV-Vis and PL. The study also investigated the influence of various reaction parameters, including the effects of inorganic and organic ions. The synthesized nanocomposite demonstrated exceptional efficiency, achieving 86â¯% and 95â¯% removal rates, with corresponding rate constants of 0.025 and 0.047â¯min-1. This performance surpasses that of CdIn2Se4 by approximately 1.35 and 2.25 times, respectively. The values of COD were decreased to 78 and 86â¯% for ofloxacin and 2,4-dichlorophenoxyacetic, while the TOC values decreased to 71 and 84â¯%, respectively, from their premier values. The improvement in performance is associated with the introduction of CdIn2Se4 into chitosan, resulting in the self-integration of Cd into the catalyst. This creates a localized accumulation point for electrons, enhancing the efficiency of charge separation and further reducing the surface charge of chitosan. Experimental evidence suggests that superoxide and hydroxyl radicals play a significant role in the photodegradation of pollutants. Additionally, the nanocomposite exhibits excellent stability and can be reused up to five times, indicating remarkable stability and reusability of the developed photocatalyst.
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Quitosana , Nanocompostos , Ofloxacino , Quitosana/química , Nanocompostos/química , Ofloxacino/química , Fotólise , Ácido 2,4-Diclorofenoxiacético/química , Catálise , Cádmio/químicaRESUMO
Rice blast disease, caused by the fungus Magnaporthe oryzae, poses a severe threat to rice production, particularly in Asia where rice is a staple food. Concerns over fungicide resistance and environmental impact have sparked interest in exploring natural fungicides as potential alternatives. This study aimed to identify highly potent natural fungicides against M. oryzae to combat rice blast disease, using advanced molecular dynamics techniques. Four key proteins (CATALASE PEROXIDASES 2, HYBRID PKS-NRPS SYNTHETASE TAS1, MANGANESE LIPOXYGENASE, and PRE-MRNA-SPLICING FACTOR CEF1) involved in M. oryzae's infection process were identified. A list of 30 plant metabolites with documented antifungal properties was compiled for evaluation as potential fungicides. Molecular docking studies revealed that 2-Coumaroylquinic acid, Myricetin, Rosmarinic Acid, and Quercetin exhibited superior binding affinities compared to reference fungicides (Azoxystrobin and Tricyclazole). High throughput molecular dynamics simulations were performed, analyzing parameters like RMSD, RMSF, Rg, SASA, hydrogen bonds, contact analysis, Gibbs free energy, and cluster analysis. The results revealed stable interactions between the selected metabolites and the target proteins, involving important hydrogen bonds and contacts. The SwissADME server analysis indicated that the metabolites possess fungicide properties, making them effective and safe fungicides with low toxicity to the environment and living beings. Additionally, bioactivity assays confirmed their biological activity as nuclear receptor ligands and enzyme inhibitors. Overall, this study offers valuable insights into potential natural fungicides for combating rice blast disease, with 2-Coumaroylquinic acid, Myricetin, Rosmarinic Acid, and Quercetin standing out as promising and environmentally friendly alternatives to conventional fungicides. These findings have significant implications for developing crop protection strategies and enhancing global food security, particularly in rice-dependent regions.
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Ascomicetos , Fungicidas Industriais , Magnaporthe , Oryza , Ácido Quínico/análogos & derivados , Antifúngicos/farmacologia , Fungicidas Industriais/farmacologia , Quercetina/farmacologia , Simulação de Acoplamento Molecular , Oryza/microbiologia , Flavonoides/farmacologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologiaRESUMO
BACKGROUND: The surge in digital media consumption, coupled with the ensuing consequences of digital addiction, has witnessed a rapid increase, particularly after the initiation of the COVID-19 pandemic. Despite some studies exploring specific technological addictions, such as internet or social media addiction, in Bangladesh, there is a noticeable gap in research focusing on digital addiction in a broader context. Thus, this study aims to investigate digital addiction among students taking the university entrance test, examining its prevalence, contributing factors, and geographical distribution using GIS techniques. METHODS: Data from a cross-sectional survey were collected from a total of 2,157 students who were taking the university entrance test at Jahangirnagar University, Bangladesh. A convenience sampling method was applied for data collection using a structured questionnaire. Statistical analyses were performed with SPSS 25 Version and AMOS 23 Version, whereas ArcGIS 10.8 Version was used for the geographical distribution of digital addiction. RESULTS: The prevalence of digital addiction was 33.1% (mean score: 16.05 ± 5.58). Those students who are attempting the test for a second time were more likely to be addicted (42.7% vs. 39.1%), but the difference was not statistically significant. Besides, the potential factors predicted for digital addiction were student status, satisfaction with previous mock tests, average monthly expenditure during the admission test preparation, and depression. No significant difference was found between digital addiction and districts. However, digital addiction was higher in the districts of Manikganj, Rajbari, Shariatpur, and Chittagong Hill Tract areas, including Rangamati, and Bandarban. CONCLUSIONS: The study emphasizes the pressing need for collaborative efforts involving educational policymakers, institutions, and parents to address the growing digital addiction among university-bound students. The recommendations focus on promoting alternative activities, enhancing digital literacy, and imposing restrictions on digital device use, which are crucial steps toward fostering a healthier digital environment and balanced relationship with technology for students.
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Sistemas de Informação Geográfica , Transtorno de Adição à Internet , Estudantes , Humanos , Feminino , Masculino , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Universidades , Estudos Transversais , Prevalência , Adulto Jovem , Transtorno de Adição à Internet/epidemiologia , Transtorno de Adição à Internet/psicologia , Bangladesh/epidemiologia , COVID-19/epidemiologia , COVID-19/psicologia , Comportamento Aditivo/epidemiologia , Comportamento Aditivo/psicologia , Adulto , Adolescente , Inquéritos e QuestionáriosRESUMO
This research work investigates the experimental work of a single-cylinder diesel engine operated with royal poinciana biodiesel blends with various proportions of 10, 20, and 30% volume with 1-butanol as an effective ignition-improving additive. The test blends were indicated as D90RP7B3 (90% diesel + 7% royal poinciana biodiesel + 3% butanol), D80RP14B6 (80% diesel + 14% royal poinciana biodiesel + 6% butanol), D70RP21B9 (70% diesel + 21% royal poinciana biodiesel + 9% butanol), and pure royal poinciana biodiesel (RP100) and diesel. The significant findings or results obtained during the experimentation are that BTE is suitable for blend D90RP7B3, and the least BSFC is found for blend D90RP7B3 in the 0.24 kg/kWh range. The inline cylinder pressures are found to be suitable for the blend D90RP7B3 in the range of 7 MPa; HRR is ideal for both the blends D90RP7B3 and D80RP14B6 in the range of 90 and 88 kJ; D90RP7B3 possesses adequate ignition delay at full load conditions 16° in crank angle advance; maximum A/F ratios are well suitable for the blend D90RP7B3 in the ratio 11:1 at higher loads. Volumetric efficiency is achieved well for all the blends and diesel; the emissions released from the royal poinciana blends, such as CO, CO2, HC, and NOX, were reduced by 14.12, 8.33, 11.1, and 18.8% compared to standard diesel. Hence, royal poinciana blends with 1-butanol can be considered the best fuels in the automobile sector.
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This study presents an in-depth investigation into the wear characteristics of ultrahigh-molecular-weight polyethylene (UHMWPE) composites reinforced with microsized MoS2 and nanosized graphite particles. The objective is to enhance the wear resistance of the UHMWPE by examining the effects of various parameters and optimizing the wear performance. To achieve this goal, wet wear tests were conducted under controlled conditions, and the results were compared between composites with micro MoS2 and nano graphite reinforcements. The Taguchi method was employed to design the experiments (DOE) using an L9 orthogonal array. Four key parameters, namely, reinforcement percentage, load, speed, and track radius, were varied systematically to analyze their impact on wear characteristics, including wear rate, frictional forces, and the coefficient of friction (COF). The data obtained from the experiments were subjected to analysis of variance (ANOVA) to identify the significant factors affecting wear behavior. Subsequently, the optimal wear parameters were determined through regression analysis, allowing for the prediction of wear characteristics under the optimum conditions. This research not only provides insights into the comparative performance of micro MoS2 and nano graphite reinforcements in UHMWPE composites but also offers a comprehensive approach to optimizing wear resistance by employing advanced statistical and experimental techniques. The findings contribute to the development of more durable and wear-resistant materials with potential applications in various industries, such as those investigated in the study, which are commonly employed, such as automotive, aerospace, medical devices, or manufacturing.
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This study investigated cyclic magneto-hydrodynamic radiative effects in Casson and Maxwell fluids, including nonlinear radiation and Arrhenius activation energy. It promotes non-Newtonian fluid use in diverse fields like industry, manufacturing, sciences, medicine, and engineering. Using boundary layer approximations, non-dimensional equations are formulated. For numerical solutions, widely recognized explicit finite difference method (EFDM) has been utilized. To ensure the robustness of EFDM results, stability and convergence tests are performed. Exploration involve a detailed sensitivity analysis by using RSM, offering a thorough understanding of influential parameters. These analyses explore complex interactions among physical parameters, affecting Nusselt number, skin friction, and Sherwood number. Maxwell fluid's velocity is more affected by periodic magnetic force than Casson fluid, during the presence of nonlinear radiation. Additionally, nonlinear thermal radiation has a greater impact on temperature and concentration profiles compared to linear radiation for both fluids. Moreover, Casson fluid has a stronger influence on the average heat transfer rate compared to Maxwell fluid with nonlinear thermal radiation which is 8.6 % greater than the Maxwell fluid. On the other hand, at constant thermal radiation (Ra), due to decrease of Brownian motion (Nb), the rate of heat transfer is reduced by 1.2 % and 0.3 % respectively for Maxwell and Casson fluid. Also, for thermophoresis parameter (Nt), this rate is reduced by 2 % and 1.6 % respectively. The investigation also revealed that the Ra exhibits a positive sensitivity towards average Nusselt number, while Nb and Nt are displayed a negative sensitivity.
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Water is an indispensable material for human life. Unfortunately, the development of industrial activities has reduced the quality of water resources in the world. Meantime, heavy metals are an important factor in water pollution due to their toxicity. This study highlights the method for the capture of heavy metal ions from wastewater using the procedure of adsorption. The adsorption of toxic heavy metal ions (Pb2+, Hg2+, and Cd2+) on Ca2C as well as Cr2C carbide-nitride MXene monolayers is investigated using the density functional theory. We have carried out the optimization of the considered MXenes by nine DFT functionals: PBE, TPSS, BP86, B3LYP, TPSSh, PBE0, CAM-B3LYP, M11, and LC-WPBE. Our results have shown a good agreement with previously measured electronic properties of the Ca2C and Cr2C MXene layers and the PBE DFT method. The calculated cohesive energy for the Ca2C and Cr2C MXene monolayers are -4.12 eV and -4.20 eV, respectively, which are in agreement with the previous studies. The results reveal that the adsorbed heavy metal ions have a substantial effect on the electronic properties of the considered MXene monolayers. Besides, our calculations show that the metal/MXene structures with higher electron transport rates display higher binding energy as well as charge transfers between the metal and Ca2C and Cr2C layers. Time-dependent density functional analysis also displayed "ligand to metal charge transfer" excitations for the metal/MXene systems. The larger Ebin for the Pb@Ca2C as well as Pb@Cr2C are according to larger redshifts which are expected (Δλ = 45 nm and 71 nm, respectively). Our results might be helpful for future research toward the application of carbide-nitride MXene materials for removing wastewater pollutants.
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Metais Pesados , Águas Residuárias , Poluentes Químicos da Água , Águas Residuárias/química , Metais Pesados/química , Adsorção , Poluentes Químicos da Água/química , Elementos de Transição/química , Teoria da Densidade Funcional , Íons/química , Purificação da Água/métodos , Modelos MolecularesRESUMO
Background: Emergency healthcare services are under intense pressure to meet increasing patient demands. Many patients presenting to emergency departments could be managed by general practitioners in general practitioner-emergency department service models. Objectives: To evaluate the effectiveness, safety, patient experience and system implications of the different general practitioner-emergency department models. Design: Mixed-methods realist evaluation. Methods: Phase 1 (2017-8), to understand current practice: rapid realist literature review, national survey and follow-up key informant interviews, national stakeholder event and safety data analysis. Phase 2 (2018-21), to collect and analyse qualitative (observations, interviews) and quantitative data (time series analysis); cost-consequences analysis of routine data; and case site data for 'marker condition' analysis from a purposive sample of 13 case sites in England and Wales. Phase 3 (2021-2), to conduct mixed-methods analysis for programme theory and toolkit development. Results: General practitioners commonly work in emergency departments, but delivery models vary widely in terms of the scope of the general practitioner role and the scale of the general practitioner service. We developed a taxonomy to describe general practitioner-emergency department service models (Integrated with the emergency department service, Parallel within the emergency department, Outside the emergency department on the hospital site) and present a programme theory as principal output of the study to describe how these service models were observed to operate. Routine data were of variable quality, limiting our analysis. Time series analysis demonstrated trends across intervention sites for: increased time spent in the emergency department; increased emergency department attendances and reattendances; and mixed results for hospital admissions. Evidence on patient experience was limited but broadly supportive; we identified department-level processes to optimise the safety of general practitioner-emergency department models. Limitations: The quality, heterogeneity and extent of routine emergency department data collection during the study period limited the conclusions. Recruitment was limited by criteria for case sites (time series requirements) and individual patients (with 'marker conditions'). Pandemic and other pressures limited data collection for marker condition analysis. Data collected and analysed were pre pandemic; new approaches such as 'telephone first' and their relevance to our findings remains unexplored. Conclusion: Findings suggest that general practitioner-emergency department service models do not meet the aim of reducing the overall emergency department waiting times and improving patient flow with limited evidence of cost savings. Qualitative data indicated that general practitioners were often valued as members of the wider emergency department team. We have developed a toolkit, based on our findings, to provide guidance for implementing and delivering general practitioner-emergency department services. Future work: The emergency care data set has since been introduced across England to help standardise data collection to facilitate further research. We would advocate the systematic capture of patient experience measures and patient-reported outcome measures as part of routine care. More could be done to support the development of the general practitioner in emergency department role, including a core set of competencies and governance structure, to reflect the different general practitioner-emergency department models and to evaluate the effectiveness and cost effectiveness to guide future policy. Study registration: This study is registered as PROSPERO CRD42017069741. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Health and Social Care Delivery Research programme (NIHR award ref: 15/145/04) and is published in full in Health and Social Care Delivery Research; Vol. 12, No. 10. See the NIHR Funding and Awards website for further award information.
Hospital emergency departments are under huge pressure. Patients are waiting many hours to be seen, some with problems that general practitioners could deal with. To reduce waiting times and improve patient care, arrangements have been put in place for general practitioners to work in or alongside emergency departments (general practitioneremergency department models). We studied the different ways of working to find out what works well, how and for whom. We brought together a lot of information. We reviewed existing evidence, sent out surveys to 184 emergency departments, spent time in the emergency departments observing how they operated and interviewing 106 staff in 13 hospitals and 24 patients who visited those emergency departments. We also looked at statistical information recorded by hospitals. Two public contributors were involved from the beginning, and we held two stakeholder events to ensure the relevance of our research to professionals and patients. Getting reliable figures to compare the various general practitioneremergency department set-ups (inside, parallel to or outside the emergency department) was difficult. Our findings suggest that over time more people are coming to emergency departments and overall waiting times did not generally improve due to general practitioneremergency department models. Evidence that general practitioners might admit fewer patients to hospital was mixed, with limited findings of cost savings. Patients were generally supportive of the care they received, although we could not speak to as many patients as we planned. The skills and experience of general practitioners were often valued as members of the wider emergency department team. We identified how the care provided was kept safe with: strong leaders, good communication between different types of staff, highly trained and experienced nurses responsible for streaming and specific training for general practitioners on how they were expected to work. We have produced a guide to help professionals develop and improve general practitioneremergency department services and we have written easy-to-read summaries of all the articles we published.