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Large carnivores have long fascinated human societies and have profound influences on ecosystems. However, their conservation represents one of the greatest challenges of our time, particularly where attacks on humans occur. Where human recreational and/or livelihood activities overlap with large carnivore ranges, conflicts can become particularly serious. Two different scenarios are responsible for such overlap: In some regions of the world, increasing human populations lead to extended encroachment into large carnivore ranges, which are subject to increasing contraction, fragmentation, and degradation. In other regions, human and large carnivore populations are expanding, thus exacerbating conflicts, especially in those areas where these species were extirpated and are now returning. We thus face the problem of learning how to live with species that can pose serious threats to humans. We collected a total of 5,440 large carnivore (Felidae, Canidae, and Ursidae; 12 species) attacks worldwide between 1950 and 2019. The number of reported attacks increased over time, especially in lower-income countries. Most attacks (68%) resulted in human injuries, whereas 32% were fatal. Although attack scenarios varied greatly within and among species, as well as in different areas of the world, factors triggering large carnivore attacks on humans largely depend on the socioeconomic context, with people being at risk mainly during recreational activities in high-income countries and during livelihood activities in low-income countries. The specific combination of local socioeconomic and ecological factors is thus a risky mix triggering large carnivore attacks on humans, whose circumstances and frequencies cannot only be ascribed to the animal species. This also implies that effective measures to reduce large carnivore attacks must also consider the diverse local ecological and social contexts.
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Canidae , Carnívoros , Ursidae , Animais , Humanos , Ecossistema , Conservação dos Recursos Naturais/métodosRESUMO
Alternative splicing (AS) is a key post-transcriptional modification that helps in increasing protein diversity. Almost 90% of the protein-coding genes in humans are known to undergo AS and code for different transcripts. Some transcripts are associated with diseases such as breast cancer, lung cancer and glioblastoma. Hence, these transcripts can serve as novel therapeutic and prognostic targets for drug discovery. Herein, we have developed a pipeline, Finding Alternative Splicing Events (FASE), as the R package that includes modules to determine the structure and concentration of transcripts using differential AS. To predict the correct structure of expressed transcripts in given conditions, FASE combines the AS events with the information of exons, introns and junctions using graph theory. The estimated concentration of predicted transcripts is reported as the relative expression in terms of log2CPM. Using FASE, we were able to identify several unique transcripts of EMILIN1 and SLK genes in the TCGA-BRCA data, which were validated using RT-PCR. The experimental study demonstrated consistent results, which signify the high accuracy and precision of the developed methods. In conclusion, the developed pipeline, FASE, can efficiently predict novel transcripts that are missed in general transcript-level differential expression analysis. It can be applied selectively from a single gene to simple or complex genome even in multiple experimental conditions for the identification of differential AS-based biomarkers, prognostic targets and novel therapeutics.
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Processamento Alternativo , Perfilação da Expressão Gênica , Humanos , RNA-Seq , Perfilação da Expressão Gênica/métodos , Genoma , Éxons , Análise de Sequência de RNARESUMO
BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder with few risk factors identified and no known cure. Gene-environment interaction is hypothesized especially for sporadic ALS cases (90-95%) which are of unknown etiology. We aimed to investigate risk factors for ALS including exposure to ambient air toxics. METHODS: This population-based case-control study included 267 ALS cases (from the United States [U.S.] Centers for Disease Control and Prevention/Agency for Toxic Substances and Disease Registry National ALS Registry and Biorepository) and 267 age, sex, and county-matched controls identified via a commercial database. Exposure assessment for 34 ambient air toxicants was performed by assigning census tract-level U.S. Environmental Protection Agency (EPA) 2011 National Air Toxics Assessment (NATA) data to participants' residential ZIP codes. Conditional logistic regression was used to compute adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for individual compounds, chemical classes, and overall exposure. Sensitivity analyses using both conditional logistic regression and Bayesian grouped weighted quartile sum (GWQS) models were performed to assess the integrity of findings. RESULTS: Using the 2011 NATA, the highest exposure quartile (Q4) compared to the lowest (Q1) of vinyl chloride (aOR = 6.00, 95% CI: 1.87-19.25), 2,4-dinitrotoluene (aOR = 5.45, 95% CI: 1.53-19.36), cyanide (aOR = 4.34, 95% CI: 1.52-12.43), cadmium (aOR = 3.30, 95% CI: 1.11-9.77), and carbon disulfide (aOR = 2.98, 95% CI: 1.00-8.91) was associated with increased odds of ALS. Residential air selenium showed an inverse association with ALS (second quartile [Q2] vs. Q1: aOR = 0.38, 95% CI: 0.18-0.79). Additionally, residential exposure to organic/chlorinated solvents (Q4 vs Q1: aOR = 2.62, 95% CI: 1.003-6.85) was associated with ALS. CONCLUSIONS: Our findings using the 2011 NATA linked by census tract to residential area provide evidence of increased ALS risk in cases compared to controls for 2,4-dinitrotoluene, vinyl chloride, cyanide, and the organic/chlorinated solvents class. This underscores the importance of ongoing surveillance of potential exposures for at-risk populations.
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Esclerose Lateral Amiotrófica , Dinitrobenzenos , Cloreto de Vinil , Humanos , Estados Unidos/epidemiologia , Estudos de Casos e Controles , Esclerose Lateral Amiotrófica/induzido quimicamente , Esclerose Lateral Amiotrófica/epidemiologia , Teorema de Bayes , Fatores de Risco , Solventes , CianetosRESUMO
The aim of the study is to expound the effect of psoriasis on salivary glands by evaluating the secretion of saliva and salivary cytokine biomarkers in patients with psoriasis. This study was conducted by recruiting 120 subjects that included 60 patients diagnosed clinically with active psoriasis and 60 healthy controls who were age and gender matched to psoriatic subjects. Unstimulated whole saliva was collected from all the subjects by spitting method, and levels of tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), interleukin-2 (IL-2), and IL-10 (IL-10) were determined via enzyme-linked immunosorbent assay (BT Lab, Shanghai, China). Secretion of saliva in psoriasis patients was considerably reduced than in healthy controls. The concentrations of pro-inflammatory cytokines (TNF-α, IFN-γ, and IL-2) were significantly increased, whereas level of anti-inflammatory cytokine (IL-10) was markedly decreased in the saliva of psoriasis patients with hyposalivation compared to healthy subjects. Our results demonstrated significant negative correlation of salivary flow rates with the disease severity. No significant correlations were obtained between salivary levels of tested cytokines and salivary flow rates in our study. Findings of the study reflect inflammation of salivary glands with reduced salivary flow rates in psoriasis patients. The inflammatory responses in salivary gland tissues by virtue of increased pro-inflammatory cytokines concentrations together with lower anti-inflammatory cytokine levels may have a role in affecting the saliva secretion in psoriasis patients. Secretion of unstimulated saliva in psoriasis patients decreases with the severity and duration of the disease.
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OBJECTIVE: The objective of this study was to analyze the potential and convenience of using mixed reality as a teaching tool for craniovertebral junction (CVJ) anomaly pathoanatomy. METHODS: CT and CT angiography images of 2 patients with CVJ anomalies were used to construct mixed reality models in the HoloMedicine application on the HoloLens 2 headset, resulting in four viewing stations. Twenty-two participants were randomly allocated into two groups, with each participant rotating through all stations for 90 seconds, each in a different order based on their group. At every station, objective questions evaluating the understanding of CVJ pathoanatomy were answered. At the end, subjective opinion on the user experience of mixed reality was provided using a 5-point Likert scale. The objective performance of the two viewing modes was compared, and a correlation between performance and participant experience was sought. Subjective feedback was compiled and correlated with experience. RESULTS: In both groups, there was a significant improvement in median (interquartile range [IQR]) objective performance with mixed reality compared with DICOM: 1) group A: case 1, median 6 (IQR 6-7) versus 5 (IQR 3-6), p = 0.009; case 2, median 6 (IQR 6-7) versus 5 (IQR 3-6), p = 0.02; 2) group B: case 1, median 6 (IQR 5-7) versus 4 (IQR 2-5), p = 0.04; case 2, median 6 (IQR 6-7) versus 5 (IQR 3-7), p = 0.03. There was significantly higher improvement in less experienced participants in both groups for both cases: 1) group A: case 1, r = -0.8665, p = 0.0005; case 2, r = -0.8002, p = 0.03; 2) group B: case 1, r = -0.6977, p = 0.01; case 2, r = -0.7417, p = 0.009. Subjectively, mixed reality was easy to use, with less disorientation due to the visible background, and it was believed to be a useful teaching tool. CONCLUSIONS: Mixed reality is an effective teaching tool for CVJ pathoanatomy, particularly for young neurosurgeons and trainees. The versatility of mixed reality and the intuitiveness of the user experience offer many potential applications, including training, intraoperative guidance, patient counseling, and individualized medicine; consequently, mixed reality has the potential to transform neurosurgery.
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Realidade Aumentada , Neurocirurgia , Humanos , Procedimentos Neurocirúrgicos/métodos , Neurocirurgiões , Competência ClínicaRESUMO
INTRODUCTION: The aim of the study was to evaluate the feasibility and outcome of laparoscopic surgery in complicated choledochal cyst (CDC) with previous interventions (laparotomy or biliary drainage). PATIENTS AND METHODS: Patients with CDC who underwent surgery from July 2014 to July 2019 were evaluated. CDC without previous interventions (Group A) was compared with CDC that had previous interventions (Group B) to assess the feasibility and outcome of laparoscopic surgery. RESULTS: In 5 years' period, 38 patients were operated for CDC. The mean age was similar in both groups (3.78 ± 2.27 in Group A and 4.08 ± 2.73 in Group B). Out of six CDC with previous intervention (Group B), five patients were previously managed at other institutions as follows: (1) Laparoscopic cholecystectomy and endoscopic retrograde cholangiopancreatography (ERCP) stenting. (2) Laparotomy for biliary peritonitis and ERCP. (3) Percutaneous drainage of the large cyst. (4) Laparoscopic cholecystectomy. (5) ERCP stenting. (6) Percutaneous drainage for biliary ascites. All patients underwent laparoscopic CDC excision and hepatico-duodenostomy. The mean duration of surgery was 160.3 ± 17.22 in Group A and 169.2 ± 17.5 in Group B ( P = 0.258). None required intraoperative blood transfusion. None had a bile leak. Drain was removed at 4.47 ± 0.98 in Group A, while at 4.17 ± 0.75 days in Group B ( P = 0.481). There was statistically no significant difference in feed starting time or length of stay. In follow-up of 6 months-3 years, all patients are asymptomatic. CONCLUSIONS: Laparoscopy in complicated CDC with previous intervention is technically tedious but is feasible. The procedure is safe and delivers a good outcome.
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Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is an autoimmune disease involving autoreactivity to proteinase 3 (PR3) as demonstrated by presence of ANCAs. While autoantibodies are screened for diagnosis, autoreactive T cells and their features are less well-studied. Here, we investigated PR3-specific CD4+T cell responses and features of autoreactive T cells in patients with PR3-AAV, using a cohort of 72 patients with either active or inactive disease. Autoreactive PR3-specific CD4+T cells producing interferon γ in response to protein stimulation were found to express the G-protein coupled receptor 56 (GPR56), a cell surface marker that distinguishes T cells with cytotoxic capacity. GPR56+CD4+T cells were significantly more prominent in the blood of patients with inactive as compared to active disease, suggesting that these cells were affected by immunosuppression and/or that they migrated from the circulation to sites of organ involvement. Indeed, GPR56+CD4+T cells were identified in T-cell infiltrates of affected kidneys and an association with immunosuppressive therapy was found. Moreover, distinct TCR gene segment usage and shared (public) T cell clones were found for the PR3-reactive TCRs. Shared T cell clones were found in different patients with AAV carrying the disease-associated HLA-DP allele, demonstrating convergence of the autoreactive T cell repertoire. Thus, we identified a CD4+T cell signature in blood and in affected kidneys that display PR3 autoreactivity and associates with T cell cytotoxicity. Our data provide a basis for novel rationales for both immune monitoring and future therapeutic intervention in PR3-AAV.
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Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Anticorpos Anticitoplasma de Neutrófilos , Humanos , Mieloblastina , Linfócitos T CD4-Positivos/metabolismo , Receptores de Antígenos de Linfócitos T , PeroxidaseRESUMO
The global pandemic crisis, coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has claimed the lives of millions of people across the world. Development and testing of anti-SARS-CoV-2 drugs or vaccines have not turned to be realistic within the timeframe needed to combat this pandemic. Here, we report a comprehensive computational approach to identify the multi-targeted drug molecules against the SARS-CoV-2 proteins, whichare crucially involved in the viral-host interaction, replication of the virus inside the host, disease progression and transmission of coronavirus infection. Virtual screening of 75 FDA-approved potential antiviral drugs against the target proteins, spike (S) glycoprotein, human angiotensin-converting enzyme 2 (hACE2), 3-chymotrypsin-like cysteine protease (3CLpro), cathepsin L (CTSL), nucleocapsid protein, RNA-dependent RNA polymerase (RdRp) and non-structural protein 6 (NSP6), resulted in the selection of seven drugs which preferentially bind to the target proteins. Further, the molecular interactions determined by molecular dynamics simulation revealed that among the 75 drug molecules, catechin can effectively bind to 3CLpro, CTSL, RBD of S protein, NSP6 and nucleocapsid protein. It is more conveniently involved in key molecular interactions, showing binding free energy (ΔGbind) in the range of -5.09 kcal/mol (CTSL) to -26.09 kcal/mol (NSP6). At the binding pocket, catechin is majorly stabilized by the hydrophobic interactions, displays ΔEvdW values: -7.59 to -37.39 kcal/mol. Thus, the structural insights of better binding affinity and favorable molecular interaction of catechin toward multiple target proteins signify that catechin can be potentially explored as a multi-targeted agent against COVID-19.
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Tratamento Farmacológico da COVID-19 , Catequina/farmacologia , Polifenóis/farmacologia , SARS-CoV-2/efeitos dos fármacos , COVID-19/virologia , Catequina/química , Catequina/uso terapêutico , Humanos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Polifenóis/uso terapêuticoRESUMO
For the first time, low trace-level removal of perfluorooctanesulfonic acid (PFOS), i.e., 20-500 µg/L (ppb), from aqueous solutions using zeolitic imidazolate framework-8 (ZIF-8)-coated copper sheet (ZIF-8@Cu) composite is reported here. In comparison with different commercial activated carbon (AC) and all-silica zeolites, the composite showed the highest removal rate of 98%, which remained consistent over a wide range of concentrations. Additionally, no adsorbent leaching from the composite was noticed, which eradicated pre-analysis steps such as filtration and centrifugation, unless needed for other adsorbents studied here. The composite displayed fast uptake with saturation reaching within 4 h, irrespective of the initial concentration. However, the morphological and structural characterization revealed surface degradation of ZIF-8 crystals, along with a decline in the crystal size. The adsorption of PFOS on ZIF-8 crystals was linked to chemisorption, as the surface degradation surges with an increase in PFOS concentration or with cyclic exposure at low concentrations. Methanol seemingly removed surface debris (partially), thus providing access to ZIF-8 beneath the surface debris. Overall, the findings demonstrate that at low trace ppb-level PFOS concentrations ZIF-8 can be considered as a possible candidate for PFOS removal, even though it suffers slow surface degradation, it also removes efficiently PFOS molecules from aqueous solutions.
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BACKGROUND: Introduction of the classification of brain tumours based on DNA methylation profile has significantly changed the diagnostic approach. Due to the paucity of data on the molecular profiling of meningiomas and their clinical implications, no effective therapies and new treatments have been implemented. METHODS: DNA methylation profiling, copy number analysis, targeted sequencing and H3K27me3 expression was performed on 35 meningiomas and 5 controls. RESULTS: Unsupervised hierarchical clustering (UHC) analysis revealed four distinct molecular subgroups: Malignant; Intermediate; Benign A, and Benign B. Molecular heterogeneity was observed within the same grade as the Intermediate, Benign A, and Benign B subgroups were composed of WHO grade 1 as well as grade 2 cases. There was association of mutations with distinct methylation subgroups (NF2, AKT1, SMO, TRAF7 and pTERT). Loss of chromosome 22q was observed across all subgroups. 1p/14q co-deletion was seen in 50% of malignant and intermediate while CDKN2A loss was predominantly observed in malignant subgroup (50%). Majority of malignant (75%) and a small proportion of other subgroups (Intermediate: 25%, Benign A: 38.5%, and Benign B: 20%) harboured H3K27me3 loss. 38,734 genes were dysregulated amongst the four subgroups. DKFZ classified 71% cases with acceptable score. On survival analysis, methylation profiling had significant impact on progression-free-survival in WHO grade1 and 2 meningiomas (p = 0.0051). CONCLUSION: Genome-wide DNA methylation profiling highlights clinically distinct molecular subgroups and heterogeneity within the same grade of meningiomas. Molecular profiling can usher in a paradigm shift in meningioma classification, prognostic prediction, and treatment strategy.
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Neoplasias Meníngeas , Meningioma , Humanos , Meningioma/genética , Meningioma/patologia , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/patologia , Histonas/genética , Metilação de DNA , Mutação , Aberrações CromossômicasRESUMO
BACKGROUND AND AIMS: Replacing lumen apposing metal stents (LAMS) with permanent indwelling plastic stents after the resolution of pancreatic fluid collections (PFC) in patients with disconnected pancreatic duct (DPD) is a debatable issue. We retrospectively evaluated the safety and efficacy of replacing LAMS with long-term indwelling transmural plastic stents in patients with DPD at head/neck of pancreas. METHODS: The database of patients with PFC who underwent endoscopic transmural drainage with LAMS over the last three years was retrospectively analyzed to identify patients with DPD at the level of the head/neck of the pancreas. The patients were divided into two groups: Group A where LAMS could be replaced with plastic stents and Group B, where LAMS could not be replaced with plastic stents. The two groups were compared for recurrence of symptoms/PFC and complications. RESULTS: Out of 53 patients studied, 39 patients (34 males; mean age: 35.7 ± 6.6 years) were included in Group A and 14 patients in Group B (11 males; mean age: 33.4 ± 5.9 years). The demographic profile as well as indwelling time of LAMS was comparable between two groups. PFC recurrence was observed in 2/39 (5.1%) patients in group A and 6/14 (42.8%) patients in group B (p = 0.0001) with one patient in group A and 5 patients in group B requiring repeat intervention for recurrent PFC. CONCLUSIONS: Long-term transmural plastic stent placement after removal of LAMS in pancreatic duct disconnection at head/neck of the pancreas is safe and effective strategy to prevent the recurrence of PFC.
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Pancreatopatias , Plásticos , Masculino , Humanos , Adulto , Estudos Retrospectivos , Pâncreas , Pancreatopatias/cirurgia , Pancreatopatias/etiologia , Stents/efeitos adversos , Drenagem/efeitos adversos , Endossonografia , Resultado do TratamentoRESUMO
PURPOSE: To determine the correlation of angiogenic growth factors and inflammatory cytokines with the clinical phenotype of ocular tuberculosis (OTB). METHODS: Vitreous fluid was analysed for cytokines in patients with OTB and non-OTB uveitis using multiplex fluorescent bead-based flow cytometric assay. The clinical phenotypes were recorded and correlated with vitreous biomarkers. RESULTS: Vitreous humour from OTB patients had elevated levels of interleukin-10 (IL-10), IL-17-A, interferon-gamma (IFN-γ), and tumour necrosis factor-alpha (TNF-α). Angiopoietin (Ang-2) levels were higher in the panuveitis phenotype. OTB posterior uveitis phenotype had relatively higher vascular endothelial growth factor (VEGF) levels and lower fibroblast growth factor (FGF) levels. Additionally, eyes with choroiditis and vasculitis had elevated levels of VEGF and Ang-2 with FGF downregulation. Both IFN-γ and IL-10 were upregulated in the choroiditis phenotype of OTB. CONCLUSION: Angiogenic growth factors and inflammatory cytokines were altered in the vitreous humour of OTB patients. IFN-γ, VEGF, and IL-10 levels are increased in choroiditis and vasculitis phenotypes. Receiver operating characteristic (ROC) curve analysis further emphasized the importance of the IFN-γ assay in the diagnosis of OTB.
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Corioidite , Tuberculose Ocular , Humanos , Citocinas/metabolismo , Interleucina-10 , Fator A de Crescimento do Endotélio Vascular , Tuberculose Ocular/diagnóstico , Peptídeos e Proteínas de Sinalização Intercelular , Interferon gama , FenótipoRESUMO
A 14-month child presenting with complaints of spastic paraplegia was diagnosed with C6-D1 intramedullary cyst. A cysto-subarachnoid shunt was performed; the patient was clinically stable in the immediate post-operative period. On post-operative day 2, the patient developed multiple episodes of generalized tonic-clonic seizures (GTCS) with altered sensorium, NCCT head revealed bilateral diffuse parieto-occipital hypodensities. MRI brain showed on T2WI and FLAIR, diffuse hyperintensities in bilateral parieto-occipital region suggestive of posterior reversible encephalopathy syndrome (PRES). The patient never experienced hypertensive episodes and was treated with anti-epileptics. The patient's symptoms improved and repeat MRI after 10 weeks revealed normal signal intensity in bilateral parieto-occipital areas. PRES after spinal surgeries is very rare and more so in pediatric cases, CSF hypotension may contribute to PRES in such cases.
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Síndrome da Leucoencefalopatia Posterior , Humanos , Criança , Síndrome da Leucoencefalopatia Posterior/diagnóstico por imagem , Síndrome da Leucoencefalopatia Posterior/etiologia , Convulsões , Imageamento por Ressonância Magnética , Neuroimagem , Vértebras CervicaisRESUMO
'Prevention is better than cure, especially when something has no cure.' Cancer, in most patients is detected at the stage beyond which it becomes noncurative. Therefore, the early detection of cancer cells can play a crucial role in enhancing the chances of a patient's survival. In this light, we present a nonfluorescent receptor used for the detection of Zn2+ ion in MDA-MB-231 carcinoma cells that exhibits fluorescence turn-on behaviour upon binding with the metal ion. In this work, the synthesis of 11,16-bis(2,6-difluorobenzene)-6,6,21,21-tetramethyl-meta-benziporpho-6,21-dimethene and its Zn2+ chloride complex have been reported. The compounds were fully characterized using UV-visible, nuclear magnetic resonance (NMR), infrared (IR) and mass spectrometry. Furthermore, the X-ray polymorphs of a meta-benziporphodimethene analogue were added. The study of its bioimaging applications in MDA-MB-231 breast cancer cells for the detection of Zn2+ ions is reported.
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Corantes Fluorescentes , Zinco , Humanos , Corantes Fluorescentes/química , Zinco/química , Metais , Fluorescência , Espectrometria de FluorescênciaRESUMO
Dy3+ -doped CaY2 Al4 SiO12 phosphors were prepared using the sol-gel method. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and energy dispersive spectroscopy analyses (EDS) were used to analyse the crystal structure, morphology, and elemental composition of the prepared samples. The luminescence behaviour of the sample was investigated using photoluminescence (PL) and thermoluminescence (TL) techniques. The prepared CaY2 Al4 SiO12 :xDy3+ phosphor showed a characteristic blue and yellow emission at ~480 and 583 nm, respectively, with an excitation wavelength of 350 nm. The most intense PL emission was found for a 4 mol% doping concentration of Dy3+ ions. The CIE diagram of the phosphor showed bluish-white colour emission. For TL studies, the prepared phosphors were irradiated with a 60 Co γ (gamma) source and the TL glow curve of the CaY2 Al4 SiO12 :0.04Dy3+ phosphor showed three overlapped peaks. For the Gaussian peaks, Chen's peak shape method was applied to determine the kinetic parameters of the samples.
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Luminescência , Difração de Raios X , Raios gama , Cinética , Microscopia Eletrônica de VarreduraRESUMO
Recently, unmanned aerial vehicles (UAVs) are deployed in Novel Coronavirus Disease-2019 (COVID-19) vaccine distribution process. To address issues of fake vaccine distribution, real-time massive UAV monitoring and control at nodal centers (NCs), the authors propose SanJeeVni, a blockchain (BC)-assisted UAV vaccine distribution at the backdrop of sixth-generation (6G) enhanced ultra-reliable low latency communication (6G-eRLLC) communication. The scheme considers user registration, vaccine request, and distribution through a public Solana BC setup, which assures a scalable transaction rate. Based on vaccine requests at production setups, UAV swarms are triggered with vaccine delivery to NCs. An intelligent edge offloading scheme is proposed to support UAV coordinates and routing path setups. The scheme is compared against fifth-generation (5G) uRLLC communication. In the simulation, we achieve and 86% improvement in service latency, 12.2% energy reduction of UAV with 76.25% more UAV coverage in 6G-eRLLC, and a significant improvement of [Formula: see text]% in storage cost against the Ethereum network, which indicates the scheme efficacy in practical setups.
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The Internet of Things (IoT) is the most abundant technology in the fields of manufacturing, automation, transportation, robotics, and agriculture, utilizing the IoT's sensors-sensing capability. It plays a vital role in digital transformation and smart revolutions in critical infrastructure environments. However, handling heterogeneous data from different IoT devices is challenging from the perspective of security and privacy issues. The attacker targets the sensor communication between two IoT devices to jeopardize the regular operations of IoT-based critical infrastructure. In this paper, we propose an artificial intelligence (AI) and blockchain-driven secure data dissemination architecture to deal with critical infrastructure security and privacy issues. First, we reduced dimensionality using principal component analysis (PCA) and explainable AI (XAI) approaches. Furthermore, we applied different AI classifiers such as random forest (RF), decision tree (DT), support vector machine (SVM), perceptron, and Gaussian Naive Bayes (GaussianNB) that classify the data, i.e., malicious or non-malicious. Furthermore, we employ an interplanetary file system (IPFS)-driven blockchain network that offers security to the non-malicious data. In addition, to strengthen the security of AI classifiers, we analyze data poisoning attacks on the dataset that manipulate sensitive data and mislead the classifier, resulting in inaccurate results from the classifiers. To overcome this issue, we provide an anomaly detection approach that identifies malicious instances and removes the poisoned data from the dataset. The proposed architecture is evaluated using performance evaluation metrics such as accuracy, precision, recall, F1 score, and receiver operating characteristic curve (ROC curve). The findings show that the RF classifier transcends other AI classifiers in terms of accuracy, i.e., 98.46%.
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Mobile applications have rapidly grown over the past few decades to offer futuristic applications, such as autonomous vehicles, smart farming, and smart city. Such applications require ubiquitous, real-time, and secure communications to deliver services quickly. Toward this aim, sixth-generation (6G) wireless technology offers superior performance with high reliability, enhanced transmission rate, and low latency. However, managing the resources of the aforementioned applications is highly complex in the precarious network. An adversary can perform various network-related attacks (i.e., data injection or modification) to jeopardize the regular operation of the smart applications. Therefore, incorporating blockchain technology in the smart application can be a prominent solution to tackle security, reliability, and data-sharing privacy concerns. Motivated by the same, we presented a case study on public safety applications that utilizes the essential characteristics of artificial intelligence (AI), blockchain, and a 6G network to handle data integrity attacks on the crime data. The case study is assessed using various performance parameters by considering blockchain scalability, packet drop ratio, and training accuracy. Lastly, we explored different research challenges of adopting blockchain in the 6G wireless network.
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Inteligência Artificial , Blockchain , Reprodutibilidade dos Testes , Inteligência , Agricultura , Segurança ComputacionalRESUMO
Topic modeling is a machine learning algorithm based on statistics that follows unsupervised machine learning techniques for mapping a high-dimensional corpus to a low-dimensional topical subspace, but it could be better. A topic model's topic is expected to be interpretable as a concept, i.e., correspond to human understanding of a topic occurring in texts. While discovering corpus themes, inference constantly uses vocabulary that impacts topic quality due to its size. Inflectional forms are in the corpus. Since words frequently appear in the same sentence and are likely to have a latent topic, practically all topic models rely on co-occurrence signals between various terms in the corpus. The topics get weaker because of the abundance of distinct tokens in languages with extensive inflectional morphology. Lemmatization is often used to preempt this problem. Gujarati is one of the morphologically rich languages, as a word may have several inflectional forms. This paper proposes a deterministic finite automaton (DFA) based lemmatization technique for the Gujarati language to transform lemmas into their root words. The set of topics is then inferred from this lemmatized corpus of Gujarati text. We employ statistical divergence measurements to identify semantically less coherent (overly general) topics. The result shows that the lemmatized Gujarati corpus learns more interpretable and meaningful subjects than unlemmatized text. Finally, results show that lemmatization curtails the size of vocabulary decreases by 16% and the semantic coherence for all three measurements-Log Conditional Probability, Pointwise Mutual Information, and Normalized Pointwise Mutual Information-from -9.39 to -7.49, -6.79 to -5.18, and -0.23 to -0.17, respectively.
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Choledochal cyst (CDC) can present with complications such as cholangitis, perforation, pancreatitis and malignancy. Compared to the open technique for CDC, advantages of laparoscopic surgery are well known. Biliary peritonitis secondary to perforation/rupture of CDC is rare and is described in <2% of cases. In ruptured CDC, there are different approaches of management like peritioneal lavage, and biliary drainage by T-tube or Cholecystosomy/choledochostomy or endoscopic retrograde cholangiopancreatography stenting and definitive repair after 4-6 weeks as two-staged procedure. Laparoscopy is a procedure of technical challenge and complexity in ruptured CDC. We discuss here our experience of single-stage laparoscopic excision and biliary reconstruction in ruptured CDC. Child was stabilised by percutaneous drain and one-stage laparoscopic reconstruction was done on day 4, reducing the burden/morbidity of carrying biliary drain, length of stay and cost factor. To the best of our knowledge one-stage laparoscopy in ruptured CDC has not been reported earlier.