Physical Invisible Backdoor Based on Camera Imaging

Backdoor attack aims to compromise a model, which returns an adversary-wanted output when a specific trigger pattern appears yet behaves normally for clean inputs. Current backdoor attacks require changing pixels of clean images, which results in poor stealthiness of attacks and increases the difficulty of the physical implementation. This paper proposes a novel physical invisible backdoor based on camera imaging without changing nature image pixels. Specifically, a compromised model returns a target label for images taken by a particular camera, while it returns correct results for other images. To implement and evaluate the proposed backdoor, we take shots of different objects from multi-angles using multiple smartphones to build a new dataset of 21,500 images. Conventional backdoor attacks work ineffectively with some classical models, such as ResNet18, over the above-mentioned dataset. Therefore, we propose a three-step training strategy to mount the backdoor attack. First, we design and train a camera identification model with the phone IDs to extract the camera fingerprint feature. Subsequently, we elaborate a special network architecture, which is easily compromised by our backdoor attack, by leveraging the attributes of the CFA interpolation algorithm and combining it with the feature extraction block in the camera identification model. Finally, we transfer the backdoor from the elaborated special network architecture to the classical architecture model via teacher-student distillation learning. Since the trigger of our method is related to the specific phone, our attack works effectively in the physical world. Experiment results demonstrate the feasibility of our proposed approach and robustness against various backdoor defenses

Case Report: A novel heterozygous nonsense mutation in KRIT1 cause hereditary cerebral cavernous malformation

Cerebral cavernous malformation (CCM) is a vascular malformation of the central nervous system and mainly characterized by enlarged capillary cavities without intervening brain parenchyma. Genetic studies have identified three disease-causing genes (CCM1/KRIT1, CCM2/MGC4607 and CCM3/PDCD10) responsible for CCM. Here, we characterized a four-generation family diagnosed with CCM and identified a novel heterozygous mutation c.1159C>T, p.Q387X in KRIT1 gene by whole exome sequencing and Sanger sequencing. The Q387X mutation resulted in premature termination of KRIT1 protein, which was predicted to be deleterious by the ACMG/AMP 2015 guideline. Our results provide novel genetic evidence support that KRIT1 mutations cause CCM, and are helpful to the treatment and genetic diagnosis of CCM

Helping the helpers: How video retrieval can assist special interest groups

Given the increasing broadcasting data and the ever decreas- ing spare time that we can spend on consuming this data, systems are required that assist us in identifying important content. Following a use case of a fictional social worker, we introduce a video retrieval system that is designed to assist special interest groups in their information gathering task

Social Comparison Orientation and Social Adaptation Among Young Chinese Adolescents: The Mediating Role of Academic Self-Concept

This study aimed to investigate the relationship among social comparison orientation, academic self-concept (ASC), and social adaptation. A total of 1658 Chinese adolescents (48.88% male; aged 14–18 years, Mage = 16.01 ± 0.86 years) voluntarily participated in this study and completed questionnaires. Structural equation modeling (SEM) was performed to test the theory-driven model. The results showed that the relationship between comparison of opinion and social adaptation was mediated by ASC but that ASC did not play a mediating role between comparison of ability and social adaptation. These findings indicated that ASC could be one mechanism explaining the link between adolescents’ social comparison orientation and social adaptation. Furthermore, it is possible to intervene in their social comparison orientation and ASC to improve adolescents’ social adaptation