Search

In current adaptive steganography study, the distortion function is used to describe pixel modification distortion cost. Distortion cost can describe the influence of pixel modification to the cover. And it plays an important actor in adaptive stegaography. Based on previous researches, in this paper, an Anisotropic Distortion cost Update strategy (ADU strategy) is proposed to adaptively update the initial distortion cost (obtained by HILL .etc) to describe the interaction between multiple embedding modifications more accurately. Based on steanographic security theorty, it is proved that clustering modification strategy can improve steganographic security through theoretical derivation. And through study on steganalysis features, it is analyzed and proved that the determination of optimal modification method of the central pixel is anisotropic and much more complicated. Following these two proofs, the image gradient and thermal conductivity are used to quantify the anisotropy of 4 neighboring pixels. Then the optimal modification method of the central pixel is calculated. Finally, the distortion cost of the central pixel can be updated based on the optimal modification method. Experiments with the optimal embedding simulator show that the ADU strategy has better performance when the scaling factor is 2; the proposed ADU strategy can effectively improve the steganography schemes, especially for steganalytic performance with maxSRMd2 features.

The existed digital steganography models and theories are not effective enough to guide the steganography processing. Based on previous studies, this paper proposes a complete digital steganography model based on additive noise. And then, with security analysis from KL divergence, the embedding optimization strategy is given through theoretical derivation needless of any side information: optimizing the embedding modification position and optimizing the embedding modification direction (+1 or − 1). Through theoretical derivation, we also obtain the quantitative relationship between the pixels modification probability and the adjacent pixels difference, and prove that modification by ±1 randomly cannot enhance steganographic security definitely. The research in this paper can provide theoretical guidance for the design of steganography algorithms. Compared with previous studies, the proposed embedding optimization strategy has outstanding advantages of being easy to implement and being effective to improve steganographic security. The experiments by optimizing LSBM and MG algorithms show that the proposed embedding optimization strategy can effectively improve each algorithm’s steganographic security at a relative small payload.

Treatment options for unstable intertrochanteric fractures include intramedullary nail and extramedullary fixation, although evidence regarding the most appropriate treatment for such fractures remains controversial. Our hypothesis was that there would be no obvious differences in mortality rates, functional outcomes and complications between the two groups. We therefore conducted a meta-analysis to compare the relative advantages of intramedullary nail and extramedullary fixation. A total of 10 randomized controlled trials including only patients with unstable intertrochanteric fractures were included in the final analysis. We found that no statistically significant difference in one-year mortality was observed between the two groups (RR: 0.78, 95% CI: 0.55–1.10, p = 0.160). Analysis of exact p values from five included studies indicated that functional outcomes were markedly better for patients of the intramedullary nail group when compared with those of the extramedullary fixation group (p = 0.0028), although evidence remains controversial. Higher incidences of all complications were noted for extramedullary fixation (RR:1.48, 95% CI: 1.12–1.96, p = 0.006). However, no significant differences in implant-related complications were observed between the two groups (RR:1.20, 95% CI: 0.73–1.97, p = 0.475). Therefore, comparing with extramedullary fixation, the intramedullary nail method would be more reliable and should be encouraging for unstable intertrochanteric fractures.

A novel multi-party quantum steganography protocol based on quantum secret sharing is proposed in this paper. Hidden channels are built in HBB and improved HBB quantum secret sharing protocols for secret messages transmitting, via the entanglement swapping of GHZ states and Bell measurement. Compared with the original protocol, there are only a few different GHZ sates transmitted in the proposed protocol, making the hidden channel with good imperceptibility. Moreover, the secret messages keep secure even when the hidden channel is under the attack from the dishonest participators, for the sub-secretmessages distributed randomly to different participators. With good imperceptibility and security, the capacity of proposed protocol is higher than previous multi-party quantum steganography protocol.

The management of posttraumatic vascular injury that presents after 8 h, or “ultra-time vascular injury”, is daunting and inciting recognition of this injury is vital. We retrospectively analyzed 29 patients with ultra-time vascular injuries to determine the patients’ demographic characteristics and identify the determinants for amputation and disability. The age distribution of the high-risk population was from 18 years to 40 years, which indicated that these patients had plenty of productive life remaining. Injuries to the lower limbs (79.31%) were over four times more common than injuries to the upper limbs (17.24%) and open and blunt injuries occurred most commonly. The overall rate of limb salvage was 82.76% (24/29) and limb function is excellent in 45.83% (11/24) of the patients. The remaining patients experienced different degrees of disability in their limbs, which was determined by the anatomic location of the injury and the presence of a combined arterial and venous injury, nerve injury and complex soft tissue injury, as well as the occurrence of compartment syndrome. Hence, we recommend limb-salvage treatment for patients with traumatic ultra-time vascular injuries, particularly for those aged between 18 years and 40 years. Furthermore, we encourage the development of limb-salvage techniques for ultra-time vascular injuries.

To the Editor: Nivolumab, an antibody that blocks the immune-checkpoint inhibitor programmed cell death protein 1 (PD-1), has recently shown some promising results in clinical trials for all nonsmall cell lung cancer subtypes.[1,2] It is required that clinic practice about anti-PD-1 antibodies provided real data never observed in previously known clinical trials. In addition, It is also needed to assess the role of nivolumab in the subsequent therapy of tyrosine kinase inhibitor (TKI) acquired resistance. A 60-year-old Chinese woman having a 1 month history of a dry cough was taken to the outpatient of the First Hospital of Taicang City. A chest computed tomography (CT) scan revealed a mass lesion (3 cm × 2 cm) on the right hilus. An abdominal CT showed multiple solid lesions in the liver [Figure 1a]. Clinically, bronchoscope biopsy and histopathological examination revealed lung adenocarcinoma (Stage IV). Chemotherapy, in which the regimen included pemetrexed at 500 mg/m2 in combination with cisplatin at 75 mg/m2, was administered with standard premedication. Due to the poor clinical status, gefitinib was alternatively administered at a daily dose of 250 mg. A good response to gefitinib was observed in lung, but the liver metastasis had clearly increased after 30 months of TKI therapy [Figure 1b]. At that point, we decided to treat the patient with nivolumab. After two courses of a single dose of nivolumab treatment at 2 mg/kg, radiographic examinations demonstrated a significant improvement in the liver lesions [Figure 1c]. Figure 1 (a) Metastatic hepatic carcinoma at diagnosis. (b) The liver metastasis had clearly increased after 30 months of TKI therapy. (c) Anti-PD-1 antibody lead to partial remission of hepatic metastatic carcinomas. (d) Within the window of follow-up (n = 35 ... However, about 1 week after the first course of nivolumab treatment, continual fevers were recorded. The co-infection was ruled out based on the negative microbiological testing and the absence of infectious symptoms. Hematologic and biochemical tests were in the normal range. A CT scan identified bilateral pleural effusion but no consolidation or progression of the primary tumor. The results of pleural effusion tests were indicative of transudate. Patient's serum levels of anti-native DNA, anti-nuclear, and anti-cardiolipin antibodies were within the normal range. Taking into account the result of extensive medical tests, we applied methylprednisolone (1.5 mg/kg) for 1 week, followed by oral prednisone at a dosage of 0.5 mg/kg of body mass a day. However, the fever of the patient was not improved during the follow-up [Figure 1d]. Immunotherapy is rapidly being integrated into oncology practice and is poised to alter the therapeutic landscape for a variety of malignancies. However, there are still some reports which pointed out that a certain proportion of Grade 3 or 4 immune-related adverse events (irAEs) of PD-1/PD-L1 inhibitors occurred.[3] Taken together, it was a rare case that exhibited the efficacy of nivolumab on progressive hepatic metastatic carcinomas resulting from TKI acquired resistance in the real world. As an irAEs, the patient suffered from adverse event shortly after administration of nivolumab and manifested with refractory and continual fever even treatment withdrawal. Financial support and sponsorship This work was supported by a grant from Key Talent of Suzhou Health (2015, to Cheng Chen). Conflicts of interest There are no conflicts of interest.