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1.
Nicotine Tob Res ; 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38470229

RESUMO

INTRODUCTION: This study examines limitations of the current regulatory framework for tobacco advertising on Instagram. We first investigate compliance with FDA warning label requirements for posts by tobacco-owned accounts. Next, we examine the prevalence of content that has been restricted in broadcast or print for its youth appeal, followed by content meeting more expansive criteria for youth appeal set forth in the FDA's guidance document. METHODS: Posts by tobacco-brand-owned accounts between January 1, 2021, and February 14, 2022, were sampled from Mintel's Comperemedia Omni database. Instagram posts from 15 accounts were examined for violations of FDA warning label requirements and content that has been restricted on other mediums, including cartoons, sports branding, unauthorized claims, and young models (N=1243). Finally, a subsample of n=453 unambiguously branded posts was coded for themes that met the FDA's criteria of resonating with younger audiences, particularly that "adolescents rely on external information as they seek to shape their own identities". RESULTS: Only 12.8% of posts had fully compliant warning labels. Content that has been in some way regulated on other mediums, such as cartoons (1.6%), unauthorized health claims (<1%), sports branding (<1%), and young models (4.4%) were infrequent. However, a conservative analysis focusing only on branded posts found that posts frequently highlighted tech elements (45%), device customizability (24.5%), vaper identity (17.7%), stylized product photography (33.6%), social media engagement (32.2%) and memes (5.7%). CONCLUSIONS: Enforcement of existing regulations on Instagram is minimal. Explicit content restrictions applying evidence-based guidance on youth-appealing advertising are needed. IMPLICATIONS: This research has important implications for enforcing and expanding advertising regulations on social media. First, Instagram's self-imposed regulations are ineffective, permitting tobacco companies to post ads from brand-owned accounts despite claiming to restrict tobacco promotion on the platform. Second, policymakers should seek to apply FDA guidance on youth-appealing advertising informed by decades of research to create explicit enforceable content restrictions that extend beyond cartoons, sports figures, and young models to include content likely to situate tobacco use within the developing self-concept of vulnerable youth such as presenting e-cigarettes as hi-tech devices, highlighting vaper identity, or infiltrating online social media culture. Finally, greater resources for enforcement are needed given the only applicable regulation, warning labels, remains largely ignored.

2.
Sci Data ; 11(1): 732, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969627

RESUMO

To explore complex biological questions, it is often necessary to access various data types from public data repositories. As the volume and complexity of biological sequence data grow, public repositories face significant challenges in ensuring that the data is easily discoverable and usable by the biological research community. To address these challenges, the National Center for Biotechnology Information (NCBI) has created NCBI Datasets. This resource provides straightforward, comprehensive, and scalable access to biological sequences, annotations, and metadata for a wide range of taxa. Following the FAIR (Findable, Accessible, Interoperable, and Reusable) data management principles, NCBI Datasets offers user-friendly web interfaces, command-line tools, and documented APIs, empowering researchers to access NCBI data seamlessly. The data is delivered as packages of sequences and metadata, thus facilitating improved data retrieval, sharing, and usability in research. Moreover, this data delivery method fosters effective data attribution and promotes its further reuse. This paper outlines the current scope of data accessible through NCBI Datasets and explains various options for exploring and downloading the data.


Assuntos
Metadados , Bases de Dados Genéticas , Estados Unidos , Armazenamento e Recuperação da Informação
3.
Clin Trials ; 8(2): 214-23, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21242173

RESUMO

BACKGROUND: To promote results in the National Lung Screening Trial (NLST) that are generalizable across the entire US population, a subset of NLST sites developed dedicated strategies for minority recruitment. PURPOSE: To report the effects of targeted strategies on the accrual of underrepresented groups, to describe participant characteristics, and to estimate the costs of targeted enrollment. METHODS: The 2002-2004 Tobacco Use Supplement was used to estimate eligible proportions of racial and ethnic categories. Strategic planning included meetings/conferences with key stakeholders and minority organizations. Potential institutions were selected based upon regional racial/ethnic diversity and proven success in recruitment of underrepresented groups. Seven institutions submitted targeted recruitment strategies with budgets. Accrual by racial/ethnic category was tracked for each institution. Cost estimates were based on itemized receipts for minority strategies relative to minority accrual. RESULTS: Of 18,842 participants enrolled, 1576 (8.4%) were minority participants. The seven institutions with targeted recruitment strategies accounted for 1223 (77.6%) of all minority participants enrolled. While there was a significant increase in the rate of minority accrual pre-implementation to post-implementation for the institutions with targeted recruitment (9.3% vs. 15.2%, p < 0.0001), there was no significant difference for the institutions without (3.5% vs. 3.8%, p = 0.46). Minority enrollees at the seven institutions tended to have less than a high school education, be economically disadvantaged, and were more often uninsured. These socio-demographic differences persisted at the seven institutions even after adjusting for race and ethnicity. The success of different strategies varied by institution, and no one strategy was successful across all institutions. Costs for implementation were also highly variable, ranging from $146 to $749 per minority enrollee. LIMITATIONS: Data on minority recruitment processes were not consistently kept at the individual institutions. In addition, participant responses via newspaper advertisements and the efforts of minority staff hired by the institutions could not be coded on Case Report Forms. CONCLUSIONS: Strategic efforts were associated with significant increases in minority enrollment. The greatest successes require that a priori goals be established based on eligible racial/ethnic proportions; the historical performance of sites in minority accrual should factor into the selection of sites; recruitment planning must begin well in advance of trial launch; and there must be endorsement by prominent representatives of the racial groups of interest.


Assuntos
Detecção Precoce de Câncer/economia , Etnicidade , Neoplasias Pulmonares/diagnóstico , Grupos Minoritários , Seleção de Pacientes , Ensaios Clínicos Controlados Aleatórios como Assunto/economia , Idoso , Custos e Análise de Custo , Feminino , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Fatores Socioeconômicos , Estados Unidos
4.
J Cardiovasc Comput Tomogr ; 14(6): 490-494, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32576456

RESUMO

BACKGROUND: Pericoronary adipose tissue (PCAT) attenuation has been identified as a marker for cardiovascular risk. The effect of contrast enhancement on fat attenuation is unknown. We aim to compare precontrast coronary scans to postcontrast CCTA for quantification of pericoronary fat volume and attenuation. METHODS: Thin slice pre- and post-contrast studies obtained at 120 kVp, heart rate <60, with no plaque or artifact in the right coronary artery (RCA) were selected. Analysis was limited to pixels -30 Hounsfield units (HU) to -190 HU and from 10 mm to 50 mm distal to the RCA origin at a radial distance equal to the vessel diameter. A subgroup with no plaque across all coronaries was also analyzed. RESULTS: Of 119 study pairs, the average RCA diameter was highly correlated at 3.85 mm (postcontrast) and 3.84 mm (precontrast), r = 0.97, p < 0.0001. The mean attenuation of pre- and postcontrast images was also highly correlated at -87.02 ±â€¯7.15 HU and -82.74 ±â€¯6.54 HU, respectively (r = 0.65, p < 0.0001). Pericoronary fat volume in the -190 to -30 HU range was 396 mm³ lower in the post contrast versus pre-contrast, consistent with higher attenuation (less negative) voxels postcontrast (p < 0.0001). Inter- and intra-reader agreement ranged 95-100% and 90% for precontrast and 85-90% for postcontrast studies, respectively. Subgroup analysis revealed precontrast attenuation -85.59 ±â€¯7.53 HU and postcontrast -82.21 ±â€¯7.15 HU were highly correlated r = 0.67, p < 0.0001. CONCLUSION: Pericoronary fat enhances with iodinated contrast, potentially explaining some of its risk-predictive capabilities. Fat attenuation and volume can be reliably measured from precontrast calcium scans, with volume quantification showing particularly strong correlation. Excellent inter- and intra-reader agreement is also demonstrated.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Tomografia Computadorizada Multidetectores , Pericárdio/diagnóstico por imagem , Tecido Adiposo/fisiopatologia , Adiposidade , Adulto , Idoso , Doença da Artéria Coronariana/fisiopatologia , Vasos Coronários/fisiopatologia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Pericárdio/fisiopatologia , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
5.
Radiol Manage ; 30(4): 22-7; quiz 28-30, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18714756

RESUMO

Advanced image processing has moved from a luxury to a necessity in the practice of medicine. A hospital's adoption of sophisticated 3D imaging entails several important steps with many factors to consider in order to be successful. Like any new hospital program, 3D post-processing should be introduced through a strategic planning process that includes administrators, physicians, and technologists to design, implement, and market a program that is scalable-one that minimizes up front costs while providing top level service. This article outlines the steps for planning, implementation, and growth of an advanced imaging program.


Assuntos
Tomada de Decisões Gerenciais , Imageamento Tridimensional , Serviço Hospitalar de Radiologia/organização & administração , Sistemas de Informação em Radiologia , Difusão de Inovações , Humanos , Investimentos em Saúde , Corpo Clínico Hospitalar , Técnicas de Planejamento , Desenvolvimento de Programas , Avaliação da Tecnologia Biomédica , Estados Unidos
6.
Biochem J ; 388(Pt 1): 93-101, 2005 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-15641941

RESUMO

Prolonged exposure to hyperoxia represents a serious danger to cells, yet little is known about the specific cellular factors that affect hyperoxia stress. By screening the yeast deletion library, we have identified genes that protect against high-O2 damage. Out of approx. 4800 mutants, 84 were identified as hyperoxia-sensitive, representing genes with diverse cellular functions, including transcription and translation, vacuole function, NADPH production, and superoxide detoxification. Superoxide plays a significant role, since the majority of hyperoxia-sensitive mutants displayed cross-sensitivity to superoxide-generating agents, and mutants with compromised SOD (superoxide dismutase) activity were particularly vulnerable to hyperoxia. By comparison, factors known to guard against H2O2 toxicity were poorly represented amongst hyperoxia-sensitive mutants. Although many cellular components are potential targets, our studies indicate that mitochondrial glutathione is particularly vulnerable to hyperoxia damage. During hyperoxia stress, mitochondrial glutathione is more susceptible to oxidation than cytosolic glutathione. Furthermore, two factors that help maintain mitochondrial GSH in the reduced form, namely the NADH kinase Pos5p and the mitochondrial glutathione reductase (Glr1p), are critical for hyperoxia resistance, whereas their cytosolic counterparts are not. Our findings are consistent with a model in which hyperoxia toxicity is manifested by superoxide-related damage and changes in the mitochondrial redox state.


Assuntos
Regulação Fúngica da Expressão Gênica/fisiologia , Oxigênio/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Glutationa/fisiologia , Mitocôndrias/fisiologia , Mutação , Oxirredução , Estresse Oxidativo , Paraquat/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo
7.
J Med Pract Manage ; 22(2): 69-70, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17181004

RESUMO

Under federal and an increasing number of state laws, disgruntled and former employees are given significant financial incentives to report fraud to federal and state regulators. This article addresses strategies for reducing the likelihood that your practice will be the target of a whistleblower suit.


Assuntos
Fraude/prevenção & controle , Denúncia de Irregularidades , Atenção à Saúde , Formulário de Reclamação de Seguro/legislação & jurisprudência , Administração da Prática Médica/organização & administração , Estados Unidos
8.
J Med Pract Manage ; 20(4): 180-2, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15779513

RESUMO

This article addresses issues a physician should consider when responding to medical research gathered by a patient from the Internet, discussing both potential medical malpractice liability and offering specific, recommended responses for physicians whose patients conduct online medical research.


Assuntos
Medicina Clínica/normas , Medicina de Família e Comunidade/legislação & jurisprudência , Internet/estatística & dados numéricos , Educação de Pacientes como Assunto , Participação do Paciente , Relações Médico-Paciente , Medicina Clínica/legislação & jurisprudência , Humanos , Serviços de Informação/estatística & dados numéricos , Responsabilidade Legal , Qualidade da Assistência à Saúde/legislação & jurisprudência , Qualidade da Assistência à Saúde/normas , Pesquisa
9.
J Med Pract Manage ; 21(1): 35-8, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16206803

RESUMO

By bringing information on medical issues to the attention of their representatives at the national and local levels, physicians can play an important role in molding policies that will affect their patients and their modes of practice. This article outlines the specific steps by which practitioners may engage law makers and their staffers to express their viewpoints and impact the legislative process.


Assuntos
Legislação Médica , Manobras Políticas , Papel do Médico , District of Columbia , Governo Federal , Humanos , Estados Unidos
10.
J Med Pract Manage ; 21(3): 133-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16471382

RESUMO

Beginning January 1, 2006, Medicare beneficiaries will have the option of enrolling in a new Medicare program covering prescription drugs. This article summarizes the new benefit, suggests the factors beneficiaries and their physicians might consider when selecting a prescription drug plan, and outlines practice implications for physician offices.


Assuntos
Seguro de Serviços Farmacêuticos/legislação & jurisprudência , Medicare/legislação & jurisprudência , Administração da Prática Médica/economia , Idoso , Centers for Medicare and Medicaid Services, U.S. , Definição da Elegibilidade , Formulários Farmacêuticos como Assunto , Humanos , Formulário de Reclamação de Seguro , Administração da Prática Médica/legislação & jurisprudência , Estados Unidos
11.
MGMA Connex ; 5(10): 50-3, 1, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16416593

RESUMO

The Department of Health and Human Services Office of Inspector General (OIG) has dramatically expanded the scope and frequency of physician fraud and abuse investigations. Further, OIG has increasingly extracted financial settlements and obtained sanctions against physicians. This article identifies seven areas of investigation that will be given highest priority.


Assuntos
Fraude/legislação & jurisprudência , Médicos , Gerenciamento da Prática Profissional/legislação & jurisprudência , Fraude/economia , Formulário de Reclamação de Seguro/legislação & jurisprudência , Gerenciamento da Prática Profissional/economia , Estados Unidos
12.
Acad Radiol ; 11(4): 419-35, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15109014

RESUMO

In this article, we use a level set-based segmentation algorithm to extract the vascular tree from magnetic resonance angiography (MRA) data sets. The classification approach depends on initializing the level sets in the 3D volume, and the level sets evolve with time to yield the blood vessels. This work introduces a high-quality initialization for the level set functions, allowing extraction of the blood vessels in 3D and elimination of non-vessel tissues. A comparison between the 2D and 3D segmentation approaches is made. The results are validated using a phantom that simulates the MRA data and show good accuracy.


Assuntos
Circulação Cerebrovascular , Apresentação de Dados , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Angiografia por Ressonância Magnética , Algoritmos , Humanos , Matemática , Imagens de Fantasmas
13.
J Med Pract Manage ; 20(2): 65-71, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15523769

RESUMO

The Stark law, first passed in 1989 and repeatedly expanded and clarified since then, has long created questions for group practices. Its primary intent is to prohibit physician referrals to entities in which the physician has a financial interest, but the details have proven confusing. The Stark law's Phase II regulations, as put forth by the Centers for Medicare and Medicaid Services, went into effect in July and attempt to offer further clarification. In this article the authors explain some of the complexities of this most recent set of Stark law regulations, especially as they apply to smaller, multi-specialty practices.


Assuntos
Prática de Grupo/legislação & jurisprudência , Autorreferência Médica/legislação & jurisprudência , Administração da Prática Médica/legislação & jurisprudência , Centers for Medicare and Medicaid Services, U.S. , Documentação , Fidelidade a Diretrizes/legislação & jurisprudência , Legislação Médica , Planos de Incentivos Médicos/legislação & jurisprudência , Participação no Risco Financeiro/legislação & jurisprudência , Especialização , Estados Unidos
14.
J Med Pract Manage ; 17(4): 175-7, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11873442

RESUMO

As physicians prepare for implementation of HIPAA, there will be times when they are asked to and may be required to release individual health information without patient consent and authorization. This third article in a four-part series highlights the situations in which a doctor may release health information without a patient's knowledge.


Assuntos
Acesso à Informação/legislação & jurisprudência , Confidencialidade/legislação & jurisprudência , Health Insurance Portability and Accountability Act , Prontuários Médicos/legislação & jurisprudência , Estados Unidos
15.
J Med Pract Manage ; 17(6): 302-4, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12122815

RESUMO

"Minimum information given with maximum politeness," Jacqueline Kennedy once directed a White House press secretary. Decades later, a pending federal health-privacy rule says nothing about courtesy but does explicitly require a "minimum necessary" standard for most disclosures of personally identifiable information. Physician practices that understand these two key words will have a head start in complying with the privacy regulations, which were published in December 2000 under authority of the Health Insurance Portability and Accountability Act of 1996 (HIPAA). This article, the final installment of a four-part series on how the HIPAA privacy rule will affect the day-to-day lives of physicians and their staffs, focuses on what the U.S. Department of Health and Human Services (DHHS) means by "minimum necessary."


Assuntos
Confidencialidade/legislação & jurisprudência , Revelação , Health Insurance Portability and Accountability Act , Sistemas Computadorizados de Registros Médicos/legislação & jurisprudência , Administração da Prática Médica/legislação & jurisprudência , Guias como Assunto , Política Organizacional , Estados Unidos
16.
Int J Biomed Imaging ; 2013: 517632, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23509444

RESUMO

Automatic detection of lung nodules is an important problem in computer analysis of chest radiographs. In this paper, we propose a novel algorithm for isolating lung abnormalities (nodules) from spiral chest low-dose CT (LDCT) scans. The proposed algorithm consists of three main steps. The first step isolates the lung nodules, arteries, veins, bronchi, and bronchioles from the surrounding anatomical structures. The second step detects lung nodules using deformable 3D and 2D templates describing typical geometry and gray-level distribution within the nodules of the same type. The detection combines the normalized cross-correlation template matching and a genetic optimization algorithm. The final step eliminates the false positive nodules (FPNs) using three features that robustly define the true lung nodules. Experiments with 200 CT data sets show that the proposed approach provided comparable results with respect to the experts.

17.
Biotechnol J ; 6(2): 195-203, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21298804

RESUMO

This paper focuses on validating our approach for monitoring the development of lung nodules detected in successive chest low-dose computed tomography (LDCT) scans of a patient. Our methodology for monitoring detected lung nodules includes 3D LDCT data registration, which is a non-rigid technique and involves two steps: (i) global target-to-prototype alignment of one scan to another using the experience gained from a prior appearance model, followed by (ii) local alignment to correct for intricate relative deformations. We propose a new approach for validating the accuracy of our algorithm for elastic lung phantoms constructed with state-of-the-art microfluidics technology and in vivo data. Fabricated from a flexible transparent polymer, i.e. polydimethylsiloxane (PDMS), the phantoms mimic the contractions and expansions of the lung and nodules as seen during normal breathing. The in vivo data in our study had been collected from a small control group of four subjects and a larger test group of 27 subjects with known ground truth (biopsy diagnosis. The growth rate and diagnostic results for both phantoms and in vivo data confirm the high accuracy of our algorithm.


Assuntos
Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Microfluídica/métodos , Imagens de Fantasmas , Humanos
18.
Inf Process Med Imaging ; 22: 772-83, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21761703

RESUMO

An alternative method for diagnosing malignant lung nodules by their shape rather than conventional growth rate is proposed. The 3D surfaces of the detected lung nodules are delineated by spherical harmonic analysis, which represents a 3D surface of the lung nodule supported by the unit sphere with a linear combination of special basis functions, called spherical harmonics (SHs). The proposed 3D shape analysis is carried out in five steps: (i) 3D lung nodule segmentation with a deformable 3D boundary controlled by two probabilistic visual appearance models (the learned prior and the estimated current appearance one); (ii) 3D Delaunay triangulation to construct a 3D mesh model of the segmented lung nodule surface; (iii) mapping this model to the unit sphere; (iv) computing the SHs for the surface, and (v) determining the number of the SHs to delineate the lung nodule. We describe the lung nodule shape complexity with a new shape index, the estimated number of the SHs, and use it for the K-nearest classification to distinguish malignant and benign lung nodules. Preliminary experiments on 327 lung nodules (153 malignant and 174 benign) resulted in the 93.6% correct classification (for the 95% confidence interval), showing that the proposed method is a promising supplement to current technologies for the early diagnosis of lung cancer.


Assuntos
Algoritmos , Imageamento Tridimensional/métodos , Reconhecimento Automatizado de Padrão/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Inteligência Artificial , Diagnóstico Precoce , Humanos , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Med Image Comput Comput Assist Interv ; 14(Pt 3): 175-82, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22003697

RESUMO

An alternative method of diagnosing malignant lung nodules by their shape, rather than conventional growth rate, is proposed. The 3D surfaces of the detected lung nodules are delineated by spherical harmonic analysis that represents a 3D surface of the lung nodule supported by the unit sphere with a linear combination of special basis functions, called Spherical Harmonics (SHs). The proposed 3D shape analysis is carried out in five steps: (i) 3D lung nodule segmentation with a deformable 3D boundary controlled by a new prior visual appearance model; (ii) 3D Delaunay triangulation to construct a 3D mesh model of the segmented lung nodule surface; (iii) mapping this model to the unit sphere; (iv) computing the SHs for the surface; and (v) determining the number of the SHs to delineate the lung nodule. We describe the lung nodule shape complexity with a new shape index, the estimated number of the SHs, and use it for the K-nearest classification into malignant and benign lung nodules. Preliminary experiments on 327 lung nodules (153 malignant and 174 benign) resulted in a classification accuracy of 93.6%, showing that the proposed method is a promising supplement to current technologies for the early diagnosis of lung cancer.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Neoplasias Pulmonares/diagnóstico , Nódulo Pulmonar Solitário/diagnóstico , Algoritmos , Detecção Precoce de Câncer , Humanos , Pulmão/patologia , Oncologia/métodos , Modelos Estatísticos , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Med Image Comput Comput Assist Interv ; 13(Pt 3): 626-33, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20879453

RESUMO

A framework for nodule feature-based extraction is presented to classify lung nodules in low-dose CT slices (LDCT) into four categories: juxta, well-circumscribed, vascularized and pleural-tail, based on the extracted information. The Scale Invariant Feature Transform (SIFT) and an adaptation to Daugman's Iris Recognition algorithm are used for analysis. The SIFT descriptor results are projected to lower-dimensional subspaces using PCA and LDA. Complex Gabor wavelet nodule response obtained from an adopted Daugman Iris Recognition algorithm revealed improvements from the original Daugman binary iris code. This showed that binarized nodule responses (codes) are inadequate for classification since nodules lack texture concentration as seen in the iris, while the SIFT algorithm projected using PCA showed robustness and precision in classification.


Assuntos
Algoritmos , Neoplasias Pulmonares/diagnóstico por imagem , Pulmão/diagnóstico por imagem , Reconhecimento Automatizado de Padrão/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Nódulo Pulmonar Solitário/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Humanos , Intensificação de Imagem Radiográfica/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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