Significant Increase In Transfer Research Articles

Adaptive momentum variance for attention-guided sparse adversarial attacks

The phenomenon that deep neural networks are vulnerable to adversarial examples has been found for several years. Under the black-box setting, transfer-based methods usually produce the adversarial examples on a white-box model, which serves as the surrogate model in the black-box attack, and hope that the same adversarial examples can also fool the black-box model. However, these methods have high success rates for the surrogate model and exhibit weak transferability for the black-box model. In addition, some studies have shown that deep neural networks are also vulnerable to sparse alterations of the input, but existing sparse attacks mainly focus on the number of attacked pixels without restricting the size of the perturbations, which is perceptible to human eyes. To address the above problems, we propose a transfer-based sparse attack method, called adaptive momentum variance based iterative gradient method with a class activation map, where the method considers a simple adaptive momentum variance and a refining perturbation mechanism to improve the transferability of adversarial examples. Also, a class activation map, which is also known as attention mechanism, is employed to explore the relationship between the number of the perturbed pixels and the attack performance in the case of limiting the intensity of perturbation. The proposed method is compared with a number of the state-of-the-art transfer-based adversarial attack methods on the ImageNet dataset, and the empirical results demonstrate that our method achieves a significant increase in transferability with only attacking about 50% of the pixels.

Universal Adversarial Attack on Attention and the Resulting Dataset DAmageNet.

Adversarial attacks on deep neural networks (DNNs) have been found for several years. However, the existing adversarial attacks have high success rates only when the information of the victim DNN is well-known or could be estimated by the structure similarity or massive queries. In this paper, we propose to Attack on Attention (AoA), a semantic property commonly shared by DNNs. AoA enjoys a significant increase in transferability when the traditional cross entropy loss is replaced with the attention loss. Since AoA alters the loss function only, it could be easily combined with other transferability-enhancement techniques and then achieve SOTA performance. We apply AoA to generate 50000 adversarial samples from ImageNet validation set to defeat many neural networks, and thus name the dataset as DAmageNet. 13 well-trained DNNs are tested on DAmageNet, and all of them have an error rate over 85 percent. Even with defenses or adversarial training, most models still maintain an error rate over 70 percent on DAmageNet. DAmageNet is the first universal adversarial dataset. It could be downloaded freely and serve as a benchmark for robustness testing and adversarial training.

Investigating the feasibility of using assessment and explanatory feedback in desktop virtual reality simulations

There is great potential in making assessment and learning complementary. In this study, we investigated the feasibility of developing a desktop virtual reality (VR) laboratory simulation on the topic of genetics, with integrated assessment using multiple choice questions based on item response theory (IRT) and feedback based on the cognitive theory of multimedia learning. A pre-test post-test design was used to investigate three research questions related to: (1) students’ perceptions of assessment in the form of MC questions within the VR genetics simulation; (2) the fit of the MC questions to the assumptions of the partial credit model (PCM) within the framework of IRT; and (3) if there was a significant increase in intrinsic motivation, self-efficacy, and transfer from pre- to post-test after using the VR genetics simulation as a classroom learning activity. The sample consisted of 208 undergraduate students taking a medical genetics course. The results showed that assessment items in the form of gamified multiple-choice questions were perceived by 97% of the students to lead to higher levels of understanding, and only 8% thought that they made the simulation more boring. Items within a simulation were found to fit the PCM and the results showed that the sample had a small significant increase in intrinsic motivation and self-efficacy, and a large significant increase in transfer following the genetics simulation. It was possible to develop assessments for online educational material and retain the relevance and connectedness of informal assessment while simultaneously serving the communicative and credibility-based functions of formal assessment, which is a great challenge facing education today.

Abstract WMP31: National Trends in Transfer of Patients With Intracerebral Hemorrhage to Teaching Hospitals

Introduction: The 2015 AHA guidelines for ICH management state that initial care of ICH patients should take place in an “ICU or a dedicated stroke unit with physician and nursing neuroscience acute care expertise”. This approach entails transferring ICH patients from community hospitals to centers with stroke expertise. Hypothesis: We explored national trends in transfer of ICH patients to teaching hospitals, and evaluated the differences in demographic, co-morbidity, resource utilization factors, and outcomes for transferred patients (TP) vs. directly admitted patients (DAP). Methods: From the National Inpatient Sample data for years 2006 to 2011, we identified patients with primary diagnosis of ICH (ICD-9 431). We assessed linear trends in the proportion of patients transferred over time using logistic regression. We constructed multivariate logistic regression models to explore the association of transfer status with inpatient mortality after controlling for significant factors. All analyses were performed using survey design variables, allowing us to report nationally-weighted estimates. Results: Our analysis subpopulation comprised of 232,009 patients, and 48,097 (20.7%, 95% CI: 17.8 - 23.9) were TP. There was a statistically significant increase in transfer over the 6 year period. (Figure 1). TP were younger, and were more likely to be white and have private insurance. The proportions of TP with hypertension, diabetes, congestive heart failure, and renal failure were also significantly smaller (Table 1). TP had lower adjusted odds of inpatient mortality as compared to DAP (Table 2). Conclusion: There is an increasing trend of transferring ICH patients to higher level of care. Care of transferred patients at specialized centers is associated with greater resource utilization and lower inpatient mortality. Evidence on optimal selection of patients benefiting from transfer, and long term functional outcomes are needed for policy planning.

Healthcare reimbursement models and orthopaedic trauma: will there be change in patient management? A survey of orthopaedic surgeons.

Healthcare reimbursement models are changing. Fee-for-service may be replaced by pay-for-performance or capitated care. The purpose of this study was to examine the potential changes in orthopaedic trauma surgery patient management based on potential shifts in policy surrounding readmission and reimbursement. An e-mail survey consisting of 3 case-based scenarios was delivered to 375 orthopaedic surgeons. Five options for management of each case were provided. Each of the 3 cases was presented in 3 different healthcare settings: scenario A, our current healthcare setting; scenario B, in which 90-day reoperation or readmission would not be reimbursed; and scenario C, in which a capitated healthcare structure paid a fixed amount per patient. The response rate was 40.3% with 151 surgeons completing the survey. A 71.1% of the respondents were in private practice settings, whereas 28.3% were in academic centers. In each case, there was significant increase in the respondents' choice to transfer patients to tertiary care centers under both the capitated and penalization systems as compared with the current fee-for-service model. This survey is the first of its kind to demonstrate through case-based scenarios that a healthcare system with readmission penalties and capitated reimbursement models may lead to a significant increase in transfer of complex orthopaedic trauma patients to tertiary care centers. Physicians should be encouraged to continue evidence-based medicine instead of making decisions due to finances, and other avenues of healthcare savings should be explored to decrease patient transfer rates with healthcare changes.

Abstracts for the forthcoming International Federation of Placenta Associations Meeting

Objectives: The mechanisms mediating amino acid transport across the basal membrane of the placental syncytiotrophoblast into the fetal circulation are not well understood. Our previous data indicate that amino acid exchangers mediate serine transport into the fetoplacental circulation in exchange for alanine but not for glutamate. This study characterises amino acid stimulation of serine transfer into the fetoplacental circulation by exchange. Methods: Human placentas (n = 4) were collected within 30 minutes of delivery and an intact cotyledon was perfused with a modified Earl’s bicarbonate buffer. The maternal arterial circulation was perfused with 50 ?mol /1 L-serine & glycine, 0.6 ?mol /1 14Cserine and 20 ?mol /1 3H-glycine. Amino acid [12.5 ?mol] boluses were administered to the fetal side inflow perfusate. 14C-serine and 3H-glycine were measured in maternal and fetal venous samples by dual label liquid scintillation counting. Data (mean ± SEM) were expressed as area under the curve (AUC) and analysed by one way ANOVA. Results: Fetal side boluses of serine leucine threonine tryptophan and glutamine all resulted in increased serine release (AUC values 242 ± 34, 132 ± 33, 309 ± 69, 85 ± 21 and 216 ± 82 nmol respectively). Following a fetal side bolus of glutamate, BCH or lysine there was no significant increase in transfer of serine. Glycine release was not significantly altered following any of the boluses. Conclusion: This study demonstrates that serine is transported into the fetoplacental circulation by amino acid exchangers in response to a range of substrates, but not lysine or BCH, substrates of systems y+L and L. This is consistent with serine transport by Systems ASC and b0+ but not Systems y+L and L.

A strong collision partner dependence for vibrational energy transfer in benzene and benzene- d6. He versus D 2

State-to-state branching ratios are reported for vibrational energy transfer in benzene and benzene- d 6 due to collisions with D 2 and with He in a supersonic free jet expansion. In both the benzene and benzene- d 6 experiments the initial vibrational level pumped was 6 1. The state-to-state branching ratios are different for D 2 compared with He in C 6H 6 and in C 6D 6. In particular, there is a significant increase in transfer to the 0 0 level for D 2 compared with He. It is postulated that this may be due to the small moment of inertia of D 2, which makes V→R transfer an important mechanism for this collision partner.