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Recent research has identified the mechanistic Target of Rapamycin Complex 2 (mTORC2) as a conserved direct effector of Ras proteins. While previous studies suggested the involvement of the Switch I (SWI) effector domain of Ras in binding mTORC2 components, the regulation of the Ras-mTORC2 pathway is not entirely understood. In Dictyostelium, mTORC2 is selectively activated by the Ras protein RasC, and the RasC-mTORC2 pathway then mediates chemotaxis to cAMP and cellular aggregation by regulating the actin cytoskeleton and promoting cAMP signal relay. Here, we investigated the role of specific residues in RasC's SWI, C-terminal allosteric domain, and hypervariable region (HVR) related to mTORC2 activation. Interestingly, our results suggest that RasC SWI residue A31, which was previously implicated in RasC-mediated aggregation, regulates RasC's specific activation by the Aimless RasGEF. On the other hand, our investigation identified a crucial role for RasC SWI residue T36, with secondary contributions from E38 and allosteric domain residues. Finally, we found that conserved basic residues and the adjacent prenylation site in the HVR, which are crucial for RasC's membrane localization, are essential for RasC-mTORC2 pathway activation by allowing for both RasC's own cAMP-induced activation and its subsequent activation of mTORC2. Therefore, our findings revealed new determinants of RasC-mTORC2 pathway specificity in Dictyostelium, contributing to a deeper understanding of Ras signaling regulation in eukaryotic cells.
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Dictyostelium , Alvo Mecanístico do Complexo 2 de Rapamicina , Transdução de Sinais , Proteínas ras , Dictyostelium/metabolismo , Dictyostelium/genética , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Alvo Mecanístico do Complexo 2 de Rapamicina/genética , Proteínas ras/metabolismo , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/genética , Proteínas de Protozoários/química , AMP Cíclico/metabolismoRESUMO
The present study elucidates the role of annealing with electric field on lamellar crystalline structure and molecular orientation of polymer chains in ferroelectric copolymer (P(VDF-TrFE)) and ferroelectric terpolymer (P(VDF-TrFE-CFE)) spin-coated thin films. The ferroelectric polymer thin films annealed under an electric field support the growth of nanostructure with an "edge-on" lamellar crystalline structure having in-plane molecular chain orientation. The poled P(VDF-TrFE) thin films have higher remnant polarization (Pr) ≈6.2 µC cm-2 and saturation polarization (Ps) ≈8.2 µC cm-2 at an applied electric field of 250 MV/m compared to unpoled thin films having Pr ≈4.7 and Ps ≈6.2 µC cm-2. Also, poled P(VDF-TrFE) thin films show lower coercive field (Ec) ≈94 MV/m compared to an unpoled thin film having Ec ≈105 MV/m. Similarly, poled PVDF-TrFE-CFE thin film shows better ferroelectric properties having Pr ≈0.4 and Ps ≈5.7 µC cm-2 at an applied electric field of 200 MV m-1 compared to unpoled thin films having Pr ≈0.4 and Ps ≈4.1 µC cm-2. The storage energy efficiency of unpoled and poled P(VDF-TrFE-CFE) thin films is measured to be ≈75% and 80%. Annealing of ferroelectric P(VDF-TrFE) polymer thin films under an electric field demonstrates improved ferroelectric and electroactive properties.
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The present study aimed to identify and characterize new sources of salt tolerance among 94 rice varieties from varied geographic origins. The genotypes were divided into five groups based on their morphological characteristics at both vegetative and reproductive stages using salinity scores from the Standard Evaluation System (SES). The experiment was designed as per CRD (Completely Randomized Design) with 2 sets of salinity treatments for 8 dS/meter and 12 dS/meter, respectively compared with one non-salinized control set. Using a Soil Plant Analysis Development (SPAD) meter, assessments of the apparent chlorophyll content (greenness) of the genotypes were done to comprehend the mechanism underlying their salt tolerance. To evaluate molecular genetic diversity, a panel of 1 K RiCA SNP markers was employed. Utilizing TASSEL 5.0 software, 598 filtered SNPs were used for molecular analysis. Whole-genome association studies (GWAS) were also used to investigate panicle number per plant (pn, tiller number per plant (till), SPAD value (spad), sterility (percent) (str), plant height (ph) and panicle length (pl. It is noteworthy that these characteristics oversee conveying the visible signs of salt damage in rice. Based on genotype data, diversity analysis divided the germplasm groups into four distinct clusters (I, II, III and IV). For the traits studied, thirteen significant marker-trait associations were discovered. According to the phenotypic screening, seven germplasm genotypes namely Koijuri, Asha, Kajal, Kaliboro, Hanumanjata, Akundi and Dular, are highly tolerant to salinity stress. The greenness of these genotypes was found to be more stable over time, indicating that these genotypes are more resistant to stress. Regarding their tolerance levels, the GWAS analysis produced comparable results, supporting that salinity-tolerant genotypes having minor alleles in significant SNP positions showed more greenness during the stress period. The Manhattan plot demonstrated that at the designated significant SNP position, the highly tolerant genotypes shared common alleles. These genotypes could therefore be seen as important genomic resources for accelerating the development and release of rice varieties that are tolerant to salinity.
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Oryza , Tolerância ao Sal , Tolerância ao Sal/genética , Oryza/genética , Estudo de Associação Genômica Ampla , Genótipo , Amantadina , SalinidadeRESUMO
The aging process of microplastics (MPs) could significantly change their physical and chemical characteristics and impact their migration behavior in soil. However, the complex effects of different cations and humic acids (HA) on the migration of aged MPs through saturated media are not clear. In this research, the migration and retention of pristine/aged PSMPs (polystyrene microplastics) under combined effects of cations (Na+, Ca2+) (ionic strength = 10 mM) and HA (0, 5, 15 mg/L) were investigated and analyzed in conjunction with the two-site kinetic retention model and DLVO theory. The findings showed that the aging process accelerated PSMPs migration under all tested conditions. Aged PSMPs were less susceptible to Ca2+ than pristine PSMPs. Under Ca2+ conditions, pristine/aged PSMPs showed higher retention than under Na+ conditions in the absence of HA. Furthermore, under Na+ conditions, the migration of aged PSMPs significantly increased at higher concentrations of HA. However, under Ca2+ conditions, the migration of aged PSMPs decreased significantly at higher concentrations of HA. In higher HA conditions, HA, Ca2+, and PSMPs interact to cause larger aggregations, resulting in the sedimentation of aged PSMPs. The DLVO calculations and two-site kinetic retention models' results showed the detention of PSMPs was irreversible under higher HA conditions (15 mg/L) with Ca2+, and aged PSMPs were more susceptible to clogging. These findings may help to understand the potential risk of migration behavior of PSMPs in the soil-groundwater environment.
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Cátions , Substâncias Húmicas , Microplásticos , Poliestirenos , Poliestirenos/química , Microplásticos/toxicidade , Cátions/química , Porosidade , Cinética , Solo/químicaRESUMO
Currently, heavy metal-resistant (HMR) marine actinomycetes have attracted much attention worldwide due to their unique capabilities. In this study, 27 marine-derived actinomycetes were isolated from coastal beaches in the Arabian Gulf of Al-Jubail in Saudi Arabia and screened for resistance to 100 mg/L of the heavy metals Cd2+, Cr6+, Cu2+, Fe2+, Pb2+, and Ni2+ using different assay techniques. Six isolates were selected as HMRs, of which two isolates, JJB5 and JJB11, exhibited the highest maximum tolerance concentrations (200- > 300 mg/L). Both isolates were the highest among six-HMR screened for their biodegradation potential of plastics low-density polyethylene, polystyrene, and polyvinyl chloride, recording the highest weight loss (15 ± 1.22 - 65 ± 1.2%) in their thin films. They also showed the highest biodegradability of the pesticides acetamiprid, chlordane, hexachlorocyclohexane, indoxacarb and lindane, indicating promising removal capacities (95.70-100%) for acetamiprid and indoxacarb using HPLC analysis. Additionally, the cell-free filtrate (CFF) of both isolates displayed the highest antimicrobial activity among the six-HMR screened against a variety of microbial test strains, recording the highest inhibition zone diameters (13.76 ± 0.66 - 26.0 ± 1.13 mm). GCâMS analyses of the ethyl acetate extract of their CFFs revealed the presence of diverse chemical compounds with a multitude of remarkable biological activities. Based on their spore morphology and wall-chemotype, they were assigned to the nocardioform-actinomycetes. Furthermore, their phenotypic characteristics, together with 16S rRNA gene sequencing (OR121525-OR121526), revealed them as Nocardia harenae JJB5 and Amycolatopsis marina JJB11. Our results suggest that marine HMR actinomycetes are promising candidates for various biotechnological applications.
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Biodegradação Ambiental , Metais Pesados , Testes de Sensibilidade Microbiana , Nocardia , RNA Ribossômico 16S , Metais Pesados/metabolismo , RNA Ribossômico 16S/genética , Nocardia/isolamento & purificação , Nocardia/genética , Nocardia/metabolismo , Arábia Saudita , Antibacterianos/farmacologia , Filogenia , Actinobacteria/metabolismo , Actinobacteria/isolamento & purificação , Actinobacteria/genética , Actinobacteria/classificação , Poluentes Químicos da Água/metabolismo , Água do Mar/microbiologia , Praguicidas/metabolismo , Farmacorresistência BacterianaRESUMO
Quantum spin liquids (QSLs) are novel phases of matter which remain quantum disordered even at the lowest temperature. They are characterized by emergent gauge fields and fractionalized quasiparticles. Here we show that the sub-kelvin thermal transport of the three-dimensional S=1/2 hyperhyperkagome quantum magnet PbCuTe_{2}O_{6} is governed by a sizeable charge-neutral fermionic contribution which is compatible with the itinerant fractionalized excitations of a spinon Fermi surface. We demonstrate that this hallmark feature of the QSL state is remarkably robust against sample crystallinity, large magnetic field, and field-induced magnetic order, ruling out the imitation of QSL features by extrinsic effects. Our findings thus reveal the characteristic low-energy features of PbCuTe_{2}O_{6} which qualify this compound as a true QSL material.
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A computational analysis has been executed to analyze the combined conduction-mixed convection heat transfer of a rotationally oscillating solid cylinder in a differentially heated square box filled with air. The conjugate mixed convective flow initiates the heat transfer process, where the left-side boundary is isothermally kept to a higher temperature, and the right-side boundary is maintained at a lower temperature. Conduction heat transfer takes place inside the solid cylinder. Navier-Stokes and heat energy conservation equations model the system in the dimensionless pressure-velocity formulation. All these equations are solved via the Galerkin finite element approach. Three different combinations of Grashof (103-105), Reynolds (32-316), and Richardson (0.1-10) numbers are examined to systematically investigate the variations of governing parameters on instantaneous Nusselt numbers and the respective time-averaged values along the hot wall. In each combination, the impacts of the oscillating amplitude and frequency and the variation of cylinder diameter are examined to perform the optimization study. Power spectrum analysis is also done using the Fast Fourier Transform in the frequency domain to visualize the principal frequency of the system. The instantaneous values of the Nusselt number exhibit a wavering pattern over time owing to the recurrent waning and waxing of the thermal boundary layer. For all the cases, the maximum diameter and oscillating amplitude of the cylinder are found to maximize the heat transfer. However, the optimized frequency of the oscillation strongly depends on the selection of the governing parameters. In addition, the principal thermal frequency of the system is determined to be independent of the oscillation frequency.
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Various abnormalities of coagulation such as primary hemostasis, secondary hemostasis and fibrinolysis have been reported in patients with subclinical and overt hypothyroidism. Platelets are major elements of primary hemostasis and endothelial repair. Platelet size, shape and number are the determinant of platelet function. The objective of this study was to assess primary hemostasis by PFA-100 (Platelet Function Analyzer-100) and its relation with TSH and FT4 levels in newly diagnosed overt and subclinical hypothyroid patients. This cross-sectional study was conducted in the Department of Physiology, Dhaka Medical College, Bangladesh from January 2016 to December 2016. Twenty overt and 20 subclinical hypothyroid patients with age ranging from 18 to 55 years were selected as study group and twenty age and sex matched healthy subjects were considered as control group. Patients were selected from Outpatients Department of Endocrinology and Nuclear Medicine & Allied Sciences of Dhaka Medical College Hospital, Dhaka on the basis of exclusion and inclusion criteria. For assessment of primary hemostasis, PFA-100 was analyzed by SIEMENS-INNOVANCE-PFA-200. For statistical analysis Unpaired Student's 't' test, Chi square test and Pearson's correlation co-efficient (r) test were performed. PFA-100 was significantly higher (p<0.001) in overt and subclinical hypothyroid patients as compared to healthy adult subjects. In overt and subclinical hypothyroidism using PFA-100, we found that the existence of a hypocoagulable state is due to a defect in primary hemostasis. Moreover, PFA-100 may replace the in-vivo bleeding time as a screening test for primary hemostasis in routine clinical practice.
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Hipotireoidismo , Adulto , Humanos , Adolescente , Adulto Jovem , Pessoa de Meia-Idade , Estudos Transversais , Bangladesh , Hipotireoidismo/diagnóstico , Hipotireoidismo/complicações , Hemostasia , TireotropinaRESUMO
To study the geogenic processes of naturally occurring radioactive materials' (NORMs') distribution, a transboundary Himalayan river (Punarbhaba) is chosen due to its trivial anthropogenic impacts. In explaining the genesis of radionuclides, transition elements (Sc, Ti, V, and Fe), rare-earth-elements (REEs: La, Eu, Ce, Yb, Sm, and Lu), Ta, Hf, Th, and U were analysed in 30 riverbed sediments collected from the Bangladeshi portion of the river. Elemental abundances and NORMs' activity were measured by neutron activation analysis and HPGe-gamma-spectrometry, respectively. Averagen=30 radioactivity concentrations of 226Ra (68.4 Bq kg-1), 232Th (85.7 Bq kg-1), and 40K (918 Bq kg-1) were 2.0-2.3-fold higher, which show elevated results compared to the corresponding world mean values. Additionally, mean-REE abundances were 1.02-1.38-times higher than those of crustal origin. Elevated (relative to earth-crust) ratios of Th/U (=3.95 ± 1.84) and 232Th/40K and statistical demonstrations invoke Th-dominant heavy minerals, indicating the role of kaolinite clay mineral abundance/granitic presence. However, Th/Yb, La/V, Hf/Sc, and Th/Sc ratios reveal the presence of felsic abundances, hydrodynamic sorting, and recycling of sedimentary minerals. Geo-environmental indices demonstrated the enrichment of chemical elements in heavy minerals, whereas radiological indices presented ionizing radiation concerns, e.g., the average absorbed-gamma-dose rate (123.1 nGy h-1) was 2.24-fold higher compared to the threshold value which might cause chronic health impacts depending on the degree of exposure. The mean excess lifetime cancer risk value for carcinogen exposure was 5.29 × 10-4 S v-1, which is â¼2-times greater than the suggested threshold. Therefore, plausible extraction of heavy minerals and using residues as building materials can alleviate the two-reconciling problems: (1) radiological risk management and (2) fluvial navigability.
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Metais Terras Raras , Monitoramento de Radiação , Radioatividade , Poluentes Radioativos do Solo , Metais Terras Raras/análise , Radioisótopos/análise , Minerais/análise , Medição de Risco , Poluentes Radioativos do Solo/análiseRESUMO
In this study, a straightforward, eco-friendly, and facile method for synthesizing iron oxide nanoparticles (IONPs) utilizing Piper chaba steam extract as a reducing and stabilizing agent has been demonstrated. The formation of stable IONPs coated with organic moieties was confirmed from UV-vis, FTIR, and EDX spectroscopy and DLS analysis. The produced IONPs are sufficiently crystalline to be superparamagnetic having a saturation magnetization value of 58 emu/g, and their spherical form and size of 9 nm were verified by XRD, VSM, SEM, and TEM investigations. In addition, the synthesized IONPs exhibited notable effectiveness in the removal of Congo Red (CR) dye with a maximum adsorption capacity of 88 mg/g. The adsorption kinetics followed pseudo-second-order kinetics, meaning the adsorption of CR on IONPs is mostly controlled by chemisorption. The adsorption isotherms of CR on the surface of IONPs follow the Langmuir isotherm model, indicating the monolayer adsorption on the homogeneous surface of IONPs through adsorbate-adsorbent interaction. The IONPs have revealed good potential for their reusability, with the adsorption efficiency remaining at about 85% after five adsorption-desorption cycles. The large-scale, safe, and cost-effective manufacturing of IONPs is made possible by this environmentally friendly process.
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A well-accessible healthcare system is an important measure of the progress of a country, as access to adequate healthcare is one of everyone's very basic human rights. When a community lives below the poverty line, unfortunately, it gets deprived of the basic human rights like healthcare, which is a reality to many resource-constrained communities around the world. The number of such resource-constrained communities in developing countries is large. Orphans present a prominent example in this regard in the context of Bangladesh. Orphans suffer greatly from many diseases due to their resource-constrained environment of livings and they are unable to take a minimum care of their own health. Their lack of resources, inadequate literacy skills, and limited (or no) access to technology leave them in such a position that they are ignorant of healthcare services available for them directly or through technological means. Considering all these unavoidable real aspects and the fact that such resource-constrained communities are very little focused in the literature for aiding them in getting bare minimum healthcare services, in this study, we leverage technology and relevant appropriate intermediaries to bridge the gap between the orphans in the orphanages and healthcare services offered by medical doctors. To accomplish so, we conduct a series of field studies over the intended communities. The orphanage teachers and administrators, being in proximity, are the most effective ones to operate as intermediaries for the orphan children, as revealed through our field studies. Therefore, we use these intermediaries to help the orphans to get basic healthcare services via an Android healthcare app called 'Shastho-sheba'. We also use our findings from the field study to specifically tailor and modify the application for intermediaries to use on behalf of the orphans so that health professionals can provide direct healthcare services to them over the Internet. Finally, we look into our proposed techno-social solution in the context of HCI to ensure that the service is used more effectively.
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Coronavirus disease 2019 (Covid-19) disease have been associated with significant mortality amongst doctors globally including Bangladesh. To delineate the clinico-epidemiological characteristics of the physician affected with Covid-19 was the objective of the study. This cross-sectional 'Facebook' based survey was conducted in the period of August 2020 to September 2020. Snowball sampling methods was followed. A total of 151 physicians affected with Covid-19 participated in this survey. Self-reported perceived severity scale (zero meaning not severe at all and ten denoting the most severe) was used. Collected data were analyzed by SPSS 25.0. Among the participants, the majority were male, 98(64.9%). The most prevalent affected age groups were 24-35 years 131(86.8%). Approximately 45.0% worked in COVID dedicated hospital. Entry-level physicians (Medical Officer or Assistant Surgeon) were the most affected 117(94.4%). One-third of the physicians had at least the one co-morbidity. Bronchial asthma, obesity and diabetes were the most frequent. Predominate symptoms of the infection were fever 94(62.3%), cough 94(62.3%) and myalgia 92(60.9%). Half of the participants had sore throat, anosmia, gastro-intestinal symptoms and one-third of the patients developed dyspnea. Perceived severity of the symptoms ranged between 2 and 6. The pattern of drug use to prevent the Covid-19 showed no uniformity. However, intake of Zinc, Vitamin C, Vitamin D, antihistamine and Ivermectin was found in 74.8%, 67.5%, 41.7%, 49.0% and 37.7% respectively. As the current pandemic continues to evolve, physicians must be equipped with appropriate knowledge, skills and must be cautious on the prevention measures against Covid-19.
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COVID-19 , Humanos , COVID-19/epidemiologia , Masculino , Feminino , Estudos Transversais , Adulto , Bangladesh/epidemiologia , Médicos/estatística & dados numéricos , Pessoa de Meia-Idade , SARS-CoV-2 , Adulto Jovem , Comorbidade , Índice de Gravidade de Doença , Inquéritos e QuestionáriosRESUMO
Objectives. This study aimed to determine patterns of respiratory, blood-borne and uropathogenic microbial pathogens among SARS-CoV-2-infected patients in a COVID-19-(coronavirus disease 2019) dedicated tertiary care hospital in Dhaka, Bangladesh. Design.This was a cross-sectional study. Setting. In a COVID-19-dedicated tertiary care hospital in Dhaka, Bangladesh, conducted from March to June 2021. Participants. Hospitalized individuals with COVID-19 infection regardless of age or sex. Primary and secondary outcome measures. The percentage of co-infected COVID-19 patients and the characterization of the micro-organisms responsible for co-infection served as the primary outcome measures. Finding any associations between co-infection and age, co-infection and sex and co-infection and comorbidity was the secondary outcome variable. Interventions. Not applicable. Results.Out of 79 patients, 61 % were male, and the mean age was 49.53 years. Co-infection was seen in 7.7 % of patients, out of which 5.1 % of isolates were from urine samples, followed by 2.6 % from blood. Bacteria isolated from urine were Enterococcus (2.6 %), coagulase-negative Staphylococcus (CONS) (1.3 %) and Enterobacter spp. (1.3 %). Pseudomonas spp. was the only organism isolated from blood sample. Mixed growth was found in nasopharyngeal and throat swabs, with the predominant species being Staphylococcus aureus and Streptococcus spp. At the time of data collection, 55.7 % of patients had been given antimicrobials, and 30.4 % of patients had been given a single antimicrobial. HBsAg was positive in 1.3 % of patients and none were anti-hepatitis C or dengue NS1Ag positive. Conclusion. Microbial infection has been seen to be associated with SARS-CoV-2 infections and is of great value in prescribing antimicrobials and reducing fatal outcomes of hospitalized patients.
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To discharge the colored effluents from industries there needs to be effective and affordable treatment options. Adsorption using reduced graphene oxide (rGO) as an adsorbent is a prominent one. In this study, green coffee bean extract (GCBE) is utilized as a safe reducing agent for the reduction of graphene oxide (GO) to synthesize rGO. The formation of rGO is confirmed by a new peak in the UV-vis spectra at 275 nm and a diffraction peak in the XRD patterns at 22°. The effective formation of rGO is further substantiated by a change in the GO peak's properties in the FTIR, EDX, and Raman spectra and a weight loss change in TGA. The SEM and TEM analyses demonstrate the effective production of the nano-sheets of rGO having exfoliated and segregated in a few layers. Furthermore, the obtained rGO exhibited outstanding efficacy in wastewater cleanup, effectively adsorbing MB as a prototype organic dye. The kinetics and isotherm study suggested that the adsorption leads by the chemisorption and monolayer formation on the homogeneous surface of rGO. The maximum adsorption capacity is found to be 89.3 mg g-1. This process offers a fresh opportunity for the economical and safe production of rGO for wastewater treatment.
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The prevalence and mobility of smartphones make these a widely used tool for environmental health research. However, their potential for determining aggregated air quality index (AQI) based on PM2.5 concentration in specific locations remains largely unexplored in the existing literature. In this paper, we thoroughly examine the challenges associated with predicting location-specific PM2.5 concentration using images taken with smartphone cameras. The focus of our study is on Dhaka, the capital of Bangladesh, due to its significant air pollution levels and the large population exposed to it. Our research involves the development of a Deep Convolutional Neural Network (DCNN), which we train using over a thousand outdoor images taken and annotated. These photos are captured at various locations in Dhaka, and their labels are based on PM2.5 concentration data obtained from the local US consulate, calculated using the NowCast algorithm. Through supervised learning, our model establishes a correlation index during training, enhancing its ability to function as a Picture-based Predictor of PM2.5 Concentration (PPPC). This enables the algorithm to calculate an equivalent daily averaged AQI index from a smartphone image. Unlike, popular overly parameterized models, our model shows resource efficiency since it uses fewer parameters. Furthermore, test results indicate that our model outperforms popular models like ViT and INN, as well as popular CNN-based models such as VGG19, ResNet50, and MobileNetV2, in predicting location-specific PM2.5 concentration. Our dataset is the first publicly available collection that includes atmospheric images and corresponding PM2.5 measurements from Dhaka. Our codes and dataset are available at https://github.com/lepotatoguy/aqi .
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Carbimazole has disadvantages on different body organs, especially the thyroid gland and, rarely, the adrenal glands. Most studies have not suggested any solution or medication for ameliorating the noxious effects of drugs on the glands. Our study focused on the production of xylooligosaccharide (XOS), which, when coadministered with carbimazole, relieves the toxic effects of the drug on the adrenal glands. In addition to accelerating the regeneration of adrenal gland cells, XOS significantly decreases the oxidative stress caused by obesity. This XOS produced by Aspergillus terreus xylanase was covalently immobilized using microbial Scleroglucan gel beads, which improved the immobilization yield, efficiency, and operational stability. Over a wide pH range (6-7.5), the covalent immobilization of xylanase on scleroglucan increased xylanase activity compared to that of its free form. Additionally, the reaction temperature was increased to 65 °C. However, the immobilized enzyme demonstrated superior thermal stability, sustaining 80.22% of its original activity at 60 °C for 120 min. Additionally, the full activity of the immobilized enzyme was sustained after 12 consecutive cycles, and the activity reached 78.33% after 18 cycles. After 41 days of storage at 4 °C, the immobilized enzyme was still active at approximately 98%. The immobilized enzyme has the capability to produce xylo-oligosaccharides (XOSs). Subsequently, these XOSs can be coadministered alongside carbimazole to mitigate the adverse effects of the drug on the adrenal glands. In addition to accelerating the regeneration of adrenal gland cells, XOS significantly decreases the oxidative stress caused by obesity.
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Glândulas Suprarrenais , Aspergillus , Carbimazol , Enzimas Imobilizadas , Oligossacarídeos , Aspergillus/efeitos dos fármacos , Oligossacarídeos/farmacologia , Oligossacarídeos/química , Enzimas Imobilizadas/metabolismo , Enzimas Imobilizadas/química , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/metabolismo , Animais , Glucuronatos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Endo-1,4-beta-Xilanases/metabolismo , Masculino , Ratos , Obesidade/tratamento farmacológicoRESUMO
Delayed wound healing is a major complication that diabetic patients suffer from due to high microbial infection susceptibility, high diabetic wound alkalinity, a low lymphangiogenesis rate, and a high inflammation rate, resulting in severe gangrene. Hence, this study aims to develop a multifunctional adhesive nanofibrous patch to promote the wound healing process. Phenytoin, sildenafil citrate, and/or nitric oxide-eluting nanoparticles were incorporated separately within the polylactic acid nanofibrous layer. Polylactic acid was fabricated in the form of highly porous nanofibrous matrices that resemble the natural structure of skin tissues in order to act as scaffolds that help cell migration and proliferation. A polylactic acid nanofibrous layer incorporating phenytoin was designed to stimulate fibroblast proliferation and inhibit inflammation. Another polylactic acid nanofibrous layer was loaded either with nitric oxide-eluting nanoparticles or sildenafil as a pro-angiogenic layer that can supply tissues with nitric oxide gas either exogenously or endogenously, respectively. The developed nanofibrous layers were in-vitro evaluated through different physicochemical, mechanical, and biological approaches. Finally, the efficiency of the prepared single multilayered patch was tested using an in-vivo alloxan-induced diabetic rats' model, which proved that the patches were able to release the incorporated cargos in a controlled manner, enhancing the wound healing process.
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Diabetes Mellitus Experimental , Nanofibras , Poliésteres , Humanos , Ratos , Animais , Óxido Nítrico , Nanofibras/química , Fenitoína , Angiogênese , Inflamação , Alicerces Teciduais/químicaRESUMO
We present a rare and complex case of a 76-year-old male patient with a history of low-grade neuroendocrine tumor (NET) of the small intestine, status post resection, who presented with recurrence of the tumor in the liver and subsequent carcinoid heart syndrome (CHS). The recurrent liver tumor caused severe tricuspid regurgitation and CHS, highlighting the rare association between NETs and CHS, particularly in the elderly population. This case underscores the importance of multidisciplinary care and close monitoring for patients with recurrent NETs and potential cardiac complications.
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Liver cancer is one of the aggressive primary tumors as evident by high rate of incidence and mortality. Conventional treatments (e.g. chemotherapy) suffer from various drawbacks including wide drug distribution, low localized drug concentration, and severe off-site toxicity. Therefore, they cannot satisfy the mounting need for safe and efficient cancer therapeutics, and alternative novel strategies are needed. Nano-based drug delivery systems (NDDSs) are among these novel approaches that can improve the overall therapeutic outcomes. NDDSs are designed to encapsulate drug molecules and target them specifically to liver cancer. Thus, NDDSs can selectively deliver therapeutic agents to the tumor cells and avoid distribution to off-target sites which should improve the safety profile of the active agents. Nonetheless, NDDSs should be well designed, in terms of the preparing materials, nanocarriers structure, and the targeting strategy, in order to accomplish these objectives. This review discusses the latest advances of NDDSs for cancer therapy with emphasis on the aforementioned essential design components. The review also entails the challenges associated with the clinical translation of NDDSs, and the future perspectives towards next-generation NDDSs.
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Background: Several minimal access approaches to the thyroid gland have been widely applied; nevertheless, such approaches are still challenging when dealing with large-sized thyroid nodules or goiters. We hereby evaluated the outcomes and highlighted the merits of endoscopic axillo-breast hemithyroidectomy (EABH) for large-sized unilateral goiters. Methods: Patients underwent EABH for unilateral large thyroid nodules ≥6 cm in its greatest dimension or unilateral large goiter (≥60 ml sonographic volume) whatever the size of its contained nodules were identified from a prospectively maintained database. Their demographic data, clinicopathological profiles, and surgical and esthetic outcomes are reported and analyzed. Results: Over a 2-year period, 33 patients matched the selection criteria. Their mean age was 34.75 ± 11.39 years. There were 30 women and 3 men. The majority of nodules were radiologically TIRADS3 and cytologically Bethesda 3. The mean sonographic dominant nodule greatest dimension was 5.29 ± 1.48 cm (range: 3-9.5 cm). The mean sonographic volume of the pathological lobe was 101.86 ± 54.45 ml (range: 60.11-236.88 ml). All cases were completed endoscopically with no conversion to open. The mean operative time was 110.76 ± 18.75 minutes. No significant postoperative complications were reported except for one case with temporary vocal cord paresis. Most (87.9%) of the patients were extremely satisfied with the procedure. Conclusion: EABH with our suggested key steps could be considered an effective valid approach for unilateral large goiters in trained hands and in patients desirous for cosmesis.