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1.
Sensors (Basel) ; 21(8)2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33923829

RESUMO

Adopting effective techniques to automatically detect and identify small drones is a very compelling need for a number of different stakeholders in both the public and private sectors. This work presents three different original approaches that competed in a grand challenge on the "Drone vs. Bird" detection problem. The goal is to detect one or more drones appearing at some time point in video sequences where birds and other distractor objects may be also present, together with motion in background or foreground. Algorithms should raise an alarm and provide a position estimate only when a drone is present, while not issuing alarms on birds, nor being confused by the rest of the scene. In particular, three original approaches based on different deep learning strategies are proposed and compared on a real-world dataset provided by a consortium of universities and research centers, under the 2020 edition of the Drone vs. Bird Detection Challenge. Results show that there is a range in difficulty among different test sequences, depending on the size and the shape visibility of the drone in the sequence, while sequences recorded by a moving camera and very distant drones are the most challenging ones. The performance comparison reveals that the different approaches perform somewhat complementary, in terms of correct detection rate, false alarm rate, and average precision.


Assuntos
Aprendizado Profundo , Algoritmos , Animais , Aves , Movimento (Física)
2.
J Clin Oncol ; 24(1): 106-14, 2006 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-16314619

RESUMO

PURPOSE: To determine whether efaproxiral, an allosteric modifier of hemoglobin, improves survival in patients with brain metastases when used as an adjunct to whole-brain radiation therapy (WBRT). PATIENTS AND METHODS: Patients with brain metastases from solid tumors and a Karnofsky performance score of > or = 70 were randomly assigned to receive WBRT with supplemental oxygen and either efaproxiral at 75 or 100 mg/kg (efaproxiral arm) or no efaproxiral (control arm). The primary end point was survival. RESULTS: The study consisted of 515 eligible patients (efaproxiral arm, n = 265; control arm, n = 250). The median survival time (MST) was 5.4 months for the efaproxiral arm versus 4.4 months for the control arm (hazard ratio [HR] = 0.87; P = .16). For the subgroup of patients with non-small-cell lung cancer (NSCLC) or breast cancer, the MST was 6.0 and 4.4 months, respectively (HR = 0.82; P = .07). Cox multiple regression analysis demonstrated a significant reduction in the risk of death for the efaproxiral arm in both primary populations. Further analysis indicated that the benefit may be restricted to the subgroup of patients with breast cancer. Response rates (radiographic complete response plus partial response) improved by 7% (P = .10) and 13% (P = .01) for all patients and for NSCLC and breast cancer patients in the efaproxiral arm, respectively. The most common severe adverse event in patients treated with efaproxiral was hypoxemia, which was reversible and effectively managed with supplemental oxygen in most patients. CONCLUSION: The addition of efaproxiral, a noncytotoxic radiation sensitizer, to WBRT may improve response rates and survival in patients with brain metastases, particularly metastases from breast cancer. A confirmatory trial for breast cancer patients has been initiated.


Assuntos
Compostos de Anilina/uso terapêutico , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/terapia , Irradiação Craniana , Propionatos/uso terapêutico , Radiossensibilizantes/uso terapêutico , Adulto , Idoso , Compostos de Anilina/efeitos adversos , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Hipóxia Celular , Terapia Combinada , Feminino , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Propionatos/efeitos adversos , Tolerância a Radiação
3.
J Clin Oncol ; 23(24): 5805-13, 2005 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-16027437

RESUMO

PURPOSE: Many cancer patients take antioxidant vitamin supplements with the hope of improving the outcome of conventional therapies and of reducing the adverse effects of these treatments. A randomized trial was conducted to determine whether supplementation with antioxidant vitamins could reduce the occurrence and severity of acute adverse effects of radiation therapy and improve quality of life without compromising treatment efficacy. PATIENTS AND METHODS: We conducted a randomized, double-blind, placebo-controlled trial among 540 head and neck cancer patients treated with radiation therapy. Patients were randomly assigned into two arms. The supplementation with alpha-tocopherol (400 IU/d) and beta-carotene (30 mg/d) or placebos was administered during radiation therapy and for 3 years thereafter. During the course of the trial, supplementation with beta-carotene was discontinued because of ethical concerns. RESULTS: Patients randomly assigned in the supplement arm tended to have less severe acute adverse effects during radiation therapy (odds ratio [OR], 0.72; 95% CI, 0.52 to 1.02). The reduction was statistically significant when the supplementation combined alpha-tocopherol and beta-carotene for adverse effects to the larynx (OR, 0.38; 95% CI, 0.21 to 0.71) and overall at any site (OR, 0.38; 95% CI, 0.20 to 0.74). Quality of life was not improved by the supplementation. The rate of local recurrence of the head and neck tumor tended to be higher in the supplement arm of the trial (hazard ratio, 1.37; 95% CI, 0.93 to 2.02). CONCLUSION: Supplementation with high doses of alpha-tocopherol and beta-carotene during radiation therapy could reduce the severity of treatment adverse effects. However, this trial suggests that use of high doses of antioxidants as adjuvant therapy might compromise radiation treatment efficacy.


Assuntos
Antioxidantes/uso terapêutico , Neoplasias de Cabeça e Pescoço/radioterapia , Lesões por Radiação/prevenção & controle , alfa-Tocoferol/uso terapêutico , beta Caroteno/uso terapêutico , Doença Aguda , Análise de Variância , Distribuição de Qui-Quadrado , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Qualidade de Vida , Análise de Sobrevida
4.
J Natl Cancer Inst ; 97(7): 481-8, 2005 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-15812073

RESUMO

BACKGROUND: Although low dietary intakes of antioxidant vitamins and minerals have been associated with higher risks of cancer, results of trials testing antioxidant supplementation for cancer chemoprevention have been equivocal. We assessed whether supplementation with antioxidant vitamins could reduce the incidence of second primary cancers among patients with head and neck cancer. METHODS: We conducted a multicenter, double-blind, placebo-controlled, randomized chemoprevention trial among 540 patients with stage I or II head and neck cancer treated by radiation therapy between October 1, 1994, and June 6, 2000. Supplementation with alpha-tocopherol (400 IU/day) and beta-carotene (30 mg/day) or placebo began on the first day of radiation therapy and continued for 3 years after the end of radiation therapy. In the course of the trial, beta-carotene supplementation was discontinued after 156 patients had enrolled because of ethical concerns. The remaining patients received alpha-tocopherol or placebo only. Survival was evaluated by Kaplan-Meier analysis. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). All statistical tests were two-sided. RESULTS: After a median follow-up of 52 months, second primary cancers and recurrences of the first tumor were diagnosed in 113 and 119 participants, respectively. The effect of supplementation on the incidence of second primary cancers varied over time. Compared with patients receiving placebo, patients receiving alpha-tocopherol supplements had a higher rate of second primary cancers during the supplementation period (HR = 2.88, 95% CI = 1.56 to 5.31) but a lower rate after supplementation was discontinued (HR = 0.41, 95% CI = 0.16 to 1.03). Similarly, the rate of having a recurrence or second primary cancer was higher during (HR = 1.86, 95% CI = 1.27 to 2.72) but lower after (HR = 0.71, 95% CI = 0.33 to 1.53) supplementation with alpha-tocopherol. The proportion of participants free of second primary cancer overall after 8 years of follow-up was similar in both arms. CONCLUSIONS: alpha-Tocopherol supplementation produced unexpected adverse effects on the occurrence of second primary cancers and on cancer-free survival.


Assuntos
Antioxidantes/administração & dosagem , Antioxidantes/efeitos adversos , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias Induzidas por Radiação/prevenção & controle , Segunda Neoplasia Primária/prevenção & controle , alfa-Tocoferol/administração & dosagem , alfa-Tocoferol/efeitos adversos , beta Caroteno/administração & dosagem , beta Caroteno/efeitos adversos , Adulto , Idoso , Anticarcinógenos/administração & dosagem , Anticarcinógenos/efeitos adversos , Fatores de Confusão Epidemiológicos , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Neoplasias Induzidas por Radiação/epidemiologia , Segunda Neoplasia Primária/epidemiologia , Segunda Neoplasia Primária/etiologia , Razão de Chances , Modelos de Riscos Proporcionais , Radioterapia/efeitos adversos , Análise de Sobrevida , Falha de Tratamento
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