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1.
Cureus ; 16(2): e54193, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38496058

RESUMO

This comprehensive article explores the transformative role of Chatbot GPT, based on the GPT-3 architecture, in revolutionizing dental education. The focus is on its impact across various facets, including personalized learning pathways, integration into virtual patient simulation scenarios, 24/7 accessibility, multilingual support, interactive dental dictionary functionality, evidence-based learning, and assessment and evaluation of dental students. The objective is to showcase how Chatbot GPT enhances educational experiences, promotes inclusivity, and aligns with contemporary pedagogical principles. Chatbot GPT emerges as a powerful ally in dental education, offering personalized learning experiences, risk-free clinical simulations, continuous accessibility, multilingual support, instant terminology assistance, evidence-based learning resources, and real-time assessment capabilities. Its adaptability caters to diverse learning needs, fostering a learner-centered approach and promoting lifelong learning for both dental students and practitioners. As a versatile tool, Chatbot GPT not only transforms the educational journey but also serves as a valuable asset for continuous professional development in the dynamic landscape of dentistry.

2.
Radiat Prot Dosimetry ; 199(20): 2464-2468, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38126868

RESUMO

In this work, copper (Cu)-doped titanium dioxide (TiO2) nanoparticles were prepared by co-precipitation. For studying the morphological properties, the copper doped titanium dioxide (TiO2:Cu) nanocrystalline structures were characterised through powder X-ray diffraction and field emission scanning electron microscopy. The prepared TiO2:Cu nanoparticles were annealed at two temperatures, namely, copper doped titanium dioxide annealed at 723 K temperayure (TC1) and copper doped titanium dioxide annealed at 1073 K temperayure (TC2). The annealed samples were exposed to gamma radiation of 10-Gy-to-25-kGy doses. Thermoluminescence and dosimetric properties were evaluated using a thermoluminescent dosemeter reader. The glow curves of the TiO2:Cu nanoparticles were analysed. The thermoluminescence (TL) response of samples exhibited good linearity between 100 Gy and 10 kGy with high sensitivity of 1755.25 (TC1) and 5587.06 (TC2) counts g-1Gy-1 and a minimum detectable dose of 2.9666 Gy (TC1) and 0.4892 Gy (TC2). The fading of signals was observed by 12% for TC1 and 10% for TC2 samples after a week of storage.


Assuntos
Cobre , Nanopartículas , Raios gama , Microscopia Eletrônica de Varredura
3.
Appl Radiat Isot ; 201: 111012, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37703810

RESUMO

This experimental approach was designed to understand the gamma interaction parameters for the essential biomolecules, including starch soluble, cholesterol, myristic acid, glucose, oxalic acid, dextrose, salicylic acid, ethyl cellulose and sucrose. The empirical determination of gamma interaction parameters, such as interaction mean-free-path (MFP), buildup factor, and effective atomic number (Zeff) was performed by measuring mass attenuation coefficient (µ/ρ) at energies of 356 keV, 511 keV, 662 keV, 1173 keV, 1275 keV and 1332 keV. This was achieved using weak radioactive sources and a NaI(Tl) scintillation spectrometer with collimated and non-collimated transmission geometry. The experimentally determined values of gamma-ray interaction parameters were obtained non-destructively and precisely agreeing with the expected values from simulations and codes. In addition, the research findings also revealed a novel trend in gamma interaction mean free path as a function of energy and variable buildup factors for the selected biomolecules. These research findings provide valuable insight into the process of gamma radiation interaction. This approach may fulfil the increasing demand of medical, technical and academic research laboratories for a cost-effective and reliable empirical methodology to understand gamma radiation interaction with matter.


Assuntos
Fótons , Raios gama
4.
Molecules ; 28(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37764303

RESUMO

Hg2+ is one of the most dangerous pollutants that can cause damage to organs and the immune system. The common detection methods of Hg2+ require sophisticated instrumentation and a long time for analysis. The purpose of this study was to develop a sensor for the detection of Hg2+ using filter paper immobilized by gold nanoparticles (AuNPs) conjugated with cyanuric acid (CA). The clear color change from pink to bluish purple is the response of the CA-AuNPs filter paper sensor to exposure to Hg2+. Detection can be observed visually with the naked eye and/or with imageJ software; the detection limit is 0.05 µM. The colorimetric response of the sensor was also selective towards Hg2+ after testing with different metal ions. In addition, the response from the sensor was also consistent for lake water samples spiked with Hg2+. The results of this research provide a promising basic technology for the development of sensors that are affordable, fast, portable, and easy to use for the detection and monitoring of Hg2+ levels in water.

5.
Entropy (Basel) ; 23(3)2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33800820

RESUMO

Datasets displaying temporal dependencies abound in science and engineering applications, with Markov models representing a simplified and popular view of the temporal dependence structure. In this paper, we consider Bayesian settings that place prior distributions over the parameters of the transition kernel of a Markov model, and seek to characterize the resulting, typically intractable, posterior distributions. We present a Probably Approximately Correct (PAC)-Bayesian analysis of variational Bayes (VB) approximations to tempered Bayesian posterior distributions, bounding the model risk of the VB approximations. Tempered posteriors are known to be robust to model misspecification, and their variational approximations do not suffer the usual problems of over confident approximations. Our results tie the risk bounds to the mixing and ergodic properties of the Markov data generating model. We illustrate the PAC-Bayes bounds through a number of example Markov models, and also consider the situation where the Markov model is misspecified.

6.
J Small Anim Pract ; 61(3): 185-189, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31960434

RESUMO

OBJECTIVES: To assess agreement between measurement of primary apocrine gland anal sac adenocarcinoma tumours using digital palpation, CT and formalin-fixed tissue and to look for associations with metastasis at presentation. MATERIALS AND METHODS: Retrospective study of different methods of measuring primary tumour size in histopathologically-confirmed canine apocrine gland anal sac adenocarcinoma. RESULTS: One hundred sixteen tumours from 107 dogs were included. There was moderate agreement between maximal dimension of the primary tumour measured by CT compared to formalin-fixed tissue and digital palpation. There was no significant difference in median maximum dimension between the measurement methods. Vascular invasion, CT stage, digital rectal examination stage and formalin-fixed tissue stage were significantly associated with metastasis at presentation, while mitotic index of the primary tumour was not. Dogs with tumours >2.5 cm (tumour-stage 2) were significantly more likely to present with metastatic disease. CLINICAL SIGNIFICANCE: In canine apocrine gland anal sac adenocarcinoma, primary tumour size, tumour-stage and vascular invasion are strong predictors of metastasis at presentation.


Assuntos
Adenocarcinoma/veterinária , Neoplasias das Glândulas Anais , Sacos Anais , Doenças do Cão , Animais , Glândulas Apócrinas , Cães , Estudos Retrospectivos
7.
Clin Med Insights Cardiol ; 11: 1179546817710026, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28579858

RESUMO

BACKGROUND: This study was designed to assess the clinical impact and cost-benefit of cardiovascular magnetic resonance imaging (CMR). In the face of current health care cost concerns, cardiac imaging modalities have come under focused review. Data related to CMR clinical impact and cost-benefit are lacking. METHODS AND RESULTS: Retrospective review of 361 consecutive patients (pts) who underwent CMR exams was conducted. Indications for CMR were tabulated for appropriateness criteria. Components of the CMR exam were identified along with evidence of clinical impact. The cost of each CMR exam was ascertained along with cost savings attributable to the CMR exam for calculation of an incremental cost-effectiveness ratio. A total of 354 of 361 pts (98%) had diagnostic quality studies. Of the 361 pts, 350 (97%) had at least 1 published Appropriateness Criterion for CMR. A significant clinical impact attributable to CMR exam results was observed in 256 of 361 pts (71%). The CMR exam resulted in a new diagnosis in 69 of 361 (27%) pts. Cardiovascular magnetic resonance imaging results avoided invasive procedures in 38 (11%) pts and prevented additional diagnostic testing in 26 (7%) pts. Comparison of health care savings using CMR as opposed to current standards of care showed a net cost savings of $833 037, ie, per patient cost savings of $2308. CONCLUSIONS: Cardiovascular magnetic resonance imaging provides diagnostic image quality in >98% of cases. Cardiovascular magnetic resonance imaging findings have documentable clinical impact on patient management in 71% of pts undergoing the exam, in a cost beneficial manner.

8.
J Small Anim Pract ; 58(4): 231-237, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28276118

RESUMO

OBJECTIVES: To report the signalment, clinical presentation, treatments pursued and outcomes of dogs with malignant anal sac melanoma. METHODS: Medical records from five institutions from January 2000 through December 2015 were reviewed and dogs with cytologically- or histologically-confirmed malignant anal sac melanoma were identified. Signalment, clinical signs, staging, cytology, histopathologic analysis, surgical and non-surgical treatments were extracted from the medical records. The referring veterinarians and owners were contacted for follow-up data. RESULTS: Eleven dogs were included and survival data was available for all. The most common clinical signs were bloody anal sac discharge and perianal licking. Initial treatments pursued included surgery (n=8), chemotherapy (n=1), and palliative treatment with pain medications and stool softeners (n=2). In an adjuvant setting, melanoma vaccine was pursued following surgery in three dogs and chemotherapy in one dog. Regardless of treatment, progression-free survival (mean 92 · 5 days) and overall survival times (median 107 days) were short. CLINICAL SIGNIFICANCE: Dogs in this case series had a guarded to poor prognosis regardless of treatment. Ten of 11 dogs were euthanased due to local or distant disease progression. Only 1 of 11 dogs was alive one year after diagnosis. An understanding of tumour behaviour in this location could lead to improved survival times with earlier diagnosis and treatment.


Assuntos
Neoplasias das Glândulas Anais , Sacos Anais , Doenças do Cão , Neoplasias das Glândulas Anais/diagnóstico , Neoplasias das Glândulas Anais/fisiopatologia , Neoplasias das Glândulas Anais/terapia , Animais , Doenças do Cão/diagnóstico , Doenças do Cão/fisiopatologia , Doenças do Cão/terapia , Cães , Feminino , Masculino
9.
J Agric Food Chem ; 61(40): 9632-7, 2013 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-24028689

RESUMO

Curcumin, a yellow bioactive component of Indian spice turmeric, is known to have a wide spectrum of biological applications. In spite of various astounding therapeutic properties, it lacks in bioavailability mainly due to its poor solubility in water. In this work, we have conjugated curcumin with silica nanoparticles to improve its aqueous solubility and hence to make it more bioavailable. Conjugation and loading of curcumin with silica nanoparticles was further examined with transmission electron microscope (TEM) and thermogravimetric analyzer. Cytotoxicity analysis of synthesized silica:curcumin conjugate was studied against HeLa cell lines as well as normal fibroblast cell lines. This study shows that silica:curcumin conjugate has great potential for anticancer application.


Assuntos
Antineoplásicos/farmacocinética , Curcumina/farmacocinética , Nanopartículas/química , Dióxido de Silício/química , Disponibilidade Biológica , Células HeLa , Humanos , Solubilidade
10.
Heart Asia ; 5(1): 80, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-27326086
11.
J Interv Cardiol ; 25(2): 140-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22295939

RESUMO

BACKGROUND: Current literature recommends weaning intra-aortic balloon pump (IABP) support prior to discontinuation. To date, no studies have compared various weaning strategies for safety or efficacy. This study was designed to evaluate the impact of weaning on in-hospital clinical outcomes. METHODS: From 5/1/07 through 5/1/09 429 patients receiving IABP therapy were retrospectively identified using CPT1 billing codes. The study population and clinical outcomes analysis were stratified by use of weaning protocols versus immediate discontinuation of the IABP. In a subset analysis the patients receiving weaning protocols prior to IABP discontinuation were stratified for further analysis of clinical outcomes by whether they had received 1:3 ratio counterpulsation during their wean or whether they only received 1:2 counterpulsation prior to IABP discontinuation. These groups were analyzed for differences in primary and secondary end-points. RESULTS: Of the 429 patients identified, 344 (80.2%) were weaned prior to IABP discontinuation and 85 (19.8%) of the patients had their IABP abruptly discontinued. Patients not weaned had a lower heart rate after IABP discontinuation than those weaned, but no difference in systolic and mean blood pressure or urine output. There was no significant difference in mortality. Weaning was associated with a nonsignificant trend toward increased length of stay. CONCLUSIONS: This study suggests that weaning protocols offer no hemodynamic benefits or improvement in in-hospital mortality rates. Weaning is associated with trend toward increased length of stay. We conclude that weaning offers no advantage over direct device removal and would advocate that balloon pumps be directly withdrawn when counterpulsation is terminated.


Assuntos
Remoção de Dispositivo/métodos , Mortalidade Hospitalar , Balão Intra-Aórtico , Choque Cardiogênico/mortalidade , Choque Cardiogênico/terapia , Idoso , Protocolos Clínicos , Feminino , Hemodinâmica , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Choque Cardiogênico/fisiopatologia
12.
J Exp Psychol Learn Mem Cogn ; 35(2): 391-407, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19271854

RESUMO

In episodic memory tasks, associations are formed between items presented close together in time. The temporal context model (TCM) hypothesizes that this contiguity effect is a consequence of shared temporal context rather than temporal proximity per se. Using double-function lists of paired associates (e.g., A-B, B-C) presented in a random order, the authors examined associations between items that were not presented close together in time but that were presented in similar temporal contexts. After learning, across-pair associations fell off with distance in the list, as if subjects had integrated the pairs into a coherent memory structure. Within-pair associations (e.g., A-B) were strongly asymmetric favoring forward transitions; across-pair associations (e.g., A-C) showed no evidence of asymmetry. While this pattern of results presented a stern challenge for a heteroassociative mediated chaining model, TCM provided an excellent fit to the data. These findings suggest that contiguity effects in episodic memory do not reflect direct associations between items but rather a process of binding, encoding, and retrieval of a gradually changing representation of temporal context.


Assuntos
Atenção , Memória de Curto Prazo , Aprendizagem por Associação de Pares , Retenção Psicológica , Atenção/fisiologia , Hipocampo/fisiologia , Humanos , Memória de Curto Prazo/fisiologia , Modelos Teóricos , Aprendizagem por Associação de Pares/fisiologia , Retenção Psicológica/fisiologia , Semântica
14.
Adv Neural Inf Process Syst ; 20: 1193-1200, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19079779

RESUMO

Semantic memory refers to our knowledge of facts and relationships between concepts. A successful semantic memory depends on inferring relationships between items that are not explicitly taught. Recent mathematical modeling of episodic memory argues that episodic recall relies on retrieval of a gradually-changing representation of temporal context. We show that retrieved context enables the development of a global memory space that reflects relationships between all items that have been previously learned. When newly-learned information is integrated into this structure, it is placed in some relationship to all other items, even if that relationship has not been explicitly learned. We demonstrate this effect for global semantic structures shaped topologically as a ring, and as a two-dimensional sheet. We also examined the utility of this learning algorithm for learning a more realistic semantic space by training it on a large pool of synonym pairs. Retrieved context enabled the model to "infer" relationships between synonym pairs that had not yet been presented.

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