928 research outputs found

    Grad-CAM++: Improved Visual Explanations for Deep Convolutional Networks

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    Over the last decade, Convolutional Neural Network (CNN) models have been highly successful in solving complex vision problems. However, these deep models are perceived as "black box" methods considering the lack of understanding of their internal functioning. There has been a significant recent interest in developing explainable deep learning models, and this paper is an effort in this direction. Building on a recently proposed method called Grad-CAM, we propose a generalized method called Grad-CAM++ that can provide better visual explanations of CNN model predictions, in terms of better object localization as well as explaining occurrences of multiple object instances in a single image, when compared to state-of-the-art. We provide a mathematical derivation for the proposed method, which uses a weighted combination of the positive partial derivatives of the last convolutional layer feature maps with respect to a specific class score as weights to generate a visual explanation for the corresponding class label. Our extensive experiments and evaluations, both subjective and objective, on standard datasets showed that Grad-CAM++ provides promising human-interpretable visual explanations for a given CNN architecture across multiple tasks including classification, image caption generation and 3D action recognition; as well as in new settings such as knowledge distillation.Comment: 17 Pages, 15 Figures, 11 Tables. Accepted in the proceedings of IEEE Winter Conf. on Applications of Computer Vision (WACV2018). Extended version is under review at IEEE Transactions on Pattern Analysis and Machine Intelligenc

    Reactivity of the Indenyl Radical (C9 H7 ) with Acetylene (C2 H2 ) and Vinylacetylene (C4 H4 ).

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    The reactions of the indenyl radicals with acetylene (C2 H2 ) and vinylacetylene (C4 H4 ) is studied in a hot chemical reactor coupled to synchrotron based vacuum ultraviolet ionization mass spectrometry. These experimental results are combined with theory to reveal that the resonantly stabilized and thermodynamically most stable 1-indenyl radical (C9 H7 . ) is always formed in the pyrolysis of 1-, 2-, 6-, and 7-bromoindenes at 1500 K. The 1-indenyl radical reacts with acetylene yielding 1-ethynylindene plus atomic hydrogen, rather than adding a second acetylene molecule and leading to ring closure and formation of fluorene as observed in other reaction mechanisms such as the hydrogen abstraction acetylene addition or hydrogen abstraction vinylacetylene addition pathways. While this reaction mechanism is analogous to the bimolecular reaction between the phenyl radical (C6 H5 . ) and acetylene forming phenylacetylene (C6 H5 CCH), the 1-indenyl+acetylene→1-ethynylindene+hydrogen reaction is highly endoergic (114 kJ mol-1 ) and slow, contrary to the exoergic (-38 kJ mol-1 ) and faster phenyl+acetylene→phenylacetylene+hydrogen reaction. In a similar manner, no ring closure leading to fluorene formation was observed in the reaction of 1-indenyl radical with vinylacetylene. These experimental results are explained through rate constant calculations based on theoretically derived potential energy surfaces

    Tissue hyaluronan expression, as reflected in the sputum of lung cancer patients, is an indicator of malignancy

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    Hyaluronan (HA) shows promise for detecting cancerous change in pleural effusion and urine. However, there is uncertainty about the localization of HA in tumor tissue and its relationship with different histological types and other components of the extracellular matrix, such as angiogenesis. We evaluated the association between HA and degree of malignancy through expression in lung tumor tissue and sputum. Tumoral tissue had significantly increased HA compared to normal tissue. Strong HA staining intensity associated with cancer cells was significant in squamous cell carcinoma compared to adenocarcinoma and large cell carcinoma. A significant direct association was found between tumors with a high percentage of HA and MVD (microvessel density) in tumoral stroma. Similarly significant was the direct association between N1 tumors and high levels of HA in cancer cells. Cox multivariate analysis showed significant association between better survival and low HA. HA increased in sputum from lung cancer patients compared to cancer-free and healthy volunteers and a significant correlation was found between HA in sputum and HA in cancer tissue. Localization of HA in tumor tissue was related to malignancy and reflected in sputum, making this an emerging factor for an important diagnostic procedure in patients suspected to have lung cancer. Further study in additional patients in a randomized prospective trial is required to finalize these results and to validate our quantitative assessment of HA, as well as to couple it to gold standard sputum cytology.Research supported by FAPESP (2010/11005-5 and 2010/04462) and CNPq (#471939/2010-2 and 483005/2012-6

    EVALUATION OF LOCALLY AVAILABLE HERBS AND SPICES ON PHYSICAL, BIOCHEMICAL AND ECONOMICAL PARAMETERS ON BROILER PRODUCTION

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    ABSTRACT: In this study, locally available eleven herbs and spices were selected in broiler diet to evaluate the growth performance, some biochemical and economical parameters of broiler. Different herbs like-cumin, myrobalan, turmeric, garlic, ginger, mushroom, black cumin, coriander, cinnamon, chilli powder and neam leaves were applied on 390 broiler chicks. A basal diet was supplemented with 1g/L antibiotic (positive control), 0g antibiotic (negative control), 1% dose of concentration of cumin, myrobalan, turmeric, garlic, ginger, mushroom, black cumin, coriander, cinnamon, chilli powder and neam leaves. At the age of 28 days, the FCR value of chilli powder, cinnamon, antibiotics, and black cumin were better (lower) than control. Significantly higher (p<0.05) dressing percentage was found in black cumin compared to the control. In this research, black cumin, cinnamon and antibiotics were showed significantly (p<0.05) lower blood glucose level than control. At 28 days of age, blood cholesterol was significantly lower (p<0.05) in neam leaves and black cumin than antibiotics and control. All treatments were significantly (p<0.05) higher antibody SP ratio for Gumboro disease compared to the control. Black cumin and cinnamon were significantly (p<0.05) higher antibody SP ratio for Newcastle disease compared to the antibiotics and control. All treatments were found significantly lower (p<0.05) E. coli population than the control. In this research cinnamon, antibiotics, black cumin and chilli were significantly (p<0.05) more profitable compared to the control. In conclusion, 1% black cumin, 1% cinnamon and 1% chilli powder were significantly (p<0.05) better for FCR, body growth, cholesterol level, sugar level in blood, immunity level, cecal microbial population, profit per bird, benefit cost ratio and can be used as good alternative of antibiotics in broiler diet

    Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

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    Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

    Emerging Pharmacotherapy for Relapsed or Refractory Hodgkin’s Lymphoma: Focus on Brentuximab Vedotin

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    Hodgkins’ lymphoma (HL) which has relapsed post or is refractory to autologous bone marrow transplant presents an ongoing treatment challenge. Development of monoclonal antibodies (mAb) for the treatment of HL has aimed to replicate the success of mAb therapy in the treatment on Non Hodgkins Lymphoma. The identification of CD30 as a potential target for treatment has led to the development of a new antibody-drug conjugate, brentuximab vedotin (SGN-35), which conjugates monomethyl auristatin E to an anti-CD30 antibody to deliver targeted toxicity to the malignant Reed Sternberg cells of HL. This review describes CD30 as an antibody target, and focuses on the antibody-drug conjugate brentuximab vedotin, including current knowledge of the mechanism of action, preclinical, clinical and pharmacokinetic data available for Brentuximab Vedotin

    Association between age and survival in a cohort of Brazilian patients with operable breast cancer

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    Whether age is an independent prognostic factor in breast cancer is a matter of debate. This is a retrospective cohort study of 767 breast cancer patients, stages I-III, treated at the Hospital das Clínicas, Minas Gerais Federal University, Belo Horizonte, Minas Gerais State, Brazil, from 2001 to 2008, aiming to study the relationship between age and survival. We included variables related to patients, tumors, and types of treatment. Different sets of Cox models were used for survival analysis. Hazard ratios (HR) and 95%CI were calculated. The relationship between age and breast cancer survival did not change substantially in any of them. In the model that accounted for all variables, women aged 70 and older (HR = 1.51, 95%CI: 1.04-2.18), and 35 or younger (HR = 1.78, 95%CI: 1.05-3.01) had shorter cancer specific survival than patients aged between 36 and 69. In addition, older age, having at least one comorbidity, and being white were associated with a higher risk of dying from other causes. In conclusion, shorter breast cancer survival is expected among the youngest and oldest patients
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