438 research outputs found
SANSCrypt: A Sporadic-Authentication-Based Sequential Logic Encryption Scheme
We propose SANSCrypt, a novel sequential logic encryption scheme to protect
integrated circuits against reverse engineering. Previous sequential encryption
methods focus on modifying the circuit state machine such that the correct
functionality can be accessed by applying the correct key sequence only once.
Considering the risk associated with one-time authentication, SANSCrypt adopts
a new temporal dimension to logic encryption, by requiring the user to
sporadically perform multiple authentications according to a protocol based on
pseudo-random number generation. Analysis and validation results on a set of
benchmark circuits show that SANSCrypt offers a substantial output
corruptibility if the key sequences are applied incorrectly. Moreover, it
exhibits an exponential resilience to existing attacks, including SAT-based
attacks, while maintaining a reasonably low overhead.Comment: This paper has been accepted at the 28th IFIP/IEEE International
Conference on Very Large Scale Integration (VLSI-SoC
A deep complementary energy method for solid mechanics using minimum complementary energy principle
In recent years, the rapid advancement of deep learning has significantly
impacted various fields, particularly in solving partial differential equations
(PDEs) in solid mechanics, benefiting greatly from the remarkable approximation
capabilities of neural networks. In solving PDEs, Physics-Informed Neural
Networks (PINNs) and the Deep Energy Method (DEM) have garnered substantial
attention. The principle of minimum potential energy and complementary energy
are two important variational principles in solid mechanics. However,DEM is
based on the principle of minimum potential energy, but it lacks the important
form of minimum complementary energy. To bridge this gap, we propose the deep
complementary energy method (DCEM) based on the principle of minimum
complementary energy. The output function of DCEM is the stress function. We
extend DCEM to DCEM-Plus (DCEM-P), adding terms that satisfy partial
differential equations. Furthermore, we propose a deep complementary energy
operator method (DCEM-O) by combining operator learning with physical
equations. We train DCEM-O using existing high-fidelity numerical results and
the complementary energy together. We present numerical results using the
Prandtl and Airy stress functions and compare DCEM with existing PINNs and DEM
when modeling representative mechanical problems. The results demonstrate that
DCEM outperforms DEM in terms of stress accuracy and efficiency and has an
advantage in dealing with complex displacement boundary conditions. DCEM-P and
DCEM-O further enhance the accuracy and efficiency of DCEM. In summary, our
proposed DCEM marks the first time that complementary energy is extended to the
energy-based physics-informed neural network and provides an essential
supplementary energy form to the DEM in solid mechanics, offering promising
research prospects in computational mechanics.Comment: 58 pages, 30 figure
Biological Activities of Chinese Propolis and Brazilian Propolis on Streptozotocin-Induced Type 1 Diabetes Mellitus in Rats
Propolis is a bee-collected natural product and has been proven to have various bioactivities. This study tested the effects of Chinese propolis and Brazilian propolis on streptozotocin-induced type 1 diabetes mellitus in Sprague-Dawley rats. The results showed that Chinese propolis and Brazilian propolis significantly inhibited body weight loss and blood glucose increase in diabetic rats. In addition, Chinese propolis-treated rats showed an 8.4% reduction of glycated hemoglobin levels compared with untreated diabetic rats. Measurement of blood lipid metabolism showed dyslipidemia in diabetic rats and Chinese propolis helped to reduce total cholesterol level by 16.6%. Moreover, oxidative stress in blood, liver and kidney was improved to various degrees by both Chinese propolis and Brazilian propolis. An apparent reduction in levels of alanine transaminase, aspartate transaminase, blood urea nitrogen and urine microalbuminuria-excretion rate demonstrated the beneficial effects of propolis in hepatorenal function. All these results suggested that Chinese propolis and Brazilian propolis can alleviate symptoms of diabetes mellitus in rats and these effects may partially be due to their antioxidant ability
Fish consumption and CHD mortality: an updated meta-analysis of seventeen cohort studies
Objective Results of studies on fish consumption and CHD mortality are inconsistent. The present updated meta-analysis was conducted to investigate the up-to-date pooling effects. Design A random-effects model was used to pool the risk estimates. Generalized least-squares regression and restricted cubic splines were used to assess the possible dose–response relationship. Subgroup analyses were conducted to examine the sources of heterogeneity. Setting PubMed and ISI Web of Science databases up to September 2010 were searched and secondary referencing qualified for inclusion in the study. Subjects Seventeen cohorts with 315 812 participants and average follow-up period of 15·9 years were identified. Results Compared with the lowest fish intake (\u3c1 serving/month or 1–3 servings/month), the pooled relative risk (RR) of fish intake on CHD mortality was 0·84 (95 % CI 0·75, 0·95) for low fish intake (1 serving/week), 0·79 (95 % CI 0·67, 0·92) for moderate fish intake (2–4 servings/week) and 0·83 (95 % CI 0·68, 1·01) for high fish intake (\u3e5 servings/week). The dose–response analysis indicated that every 15 g/d increment of fish intake decreased the risk of CHD mortality by 6 % (RR = 0·94; 95 % CI 0·90, 0·98). The method of dietary assessment, gender and energy adjustment affected the results remarkably. Conclusions Our results indicate that either low (1 serving/week) or moderate fish consumption (2–4 servings/week) has a significantly beneficial effect on the prevention of CHD mortality. High fish consumption (\u3e5 servings/week) possesses only a marginally protective effect on CHD mortality, possibly due to the limited studies included in this group
Cloning of a gene encoding glycosyltransferase from Pueraria lobata (Wild.) Ohwi and its expression in Pichia pastoris
The key enzyme of puerarin biosynthesis in Pueraria lobata (Willd.) Ohwi was unclear but may involve glycosylation. To investigate the regulation of puerarin biosynthesis, a putative UDP-dependent glycosyltransferase (UGT) gene, PlUGT1 was isolated from P. lobata root, which contained abundant puerarin. PlUGT1 encoded 480 deduced amino acid residues with a conserved UDP-glucose-binding domain, which has 61 to 84% similarity to homologues from other plant species. SDS polyacrylamide gel electrophoresis and western blotting results showed that, fusion protein migrated as a single protein band with a molecular weight of 55 kDa. A yeast expression vector pPICZA-PlUGT1 was constructed and was transformed into Pichia pastoris strain GS115. Several recombinants containing multi-copy expression cassettes were obtained on the zeocin-YPD plate and confirmed by southern dot blotting. The yield of PlUGT1 attained 0.05 g/l when recombinant cells were cultured at pH 5.5, 30°C and induced with 0.5% methanol for 72 h. The expression of PlUGT1 protein correlates positively with the copy numbers of PlUGT1 in transformed yeast cells. These results suggest that, the PlUGT1 protein can be expressed efficiently in the P. pastoris expression system and may supply a new economic and convenient way for the production of PlUGT1 protein.Keywords: Pueraria lobata (Willd.) Ohwi, glycosyltransferase, cloning, expression, Pichia pastori
Stability of Uncertain Impulsive Stochastic Genetic Regulatory Networks with Time-Varying Delay in the Leakage Term
This paper is concerned with the stability problem for a class of uncertain impulsive stochastic genetic regulatory networks (UISGRNs) with time-varying delays both in the leakage term and in the regulator function. By constructing a suitable Lyapunov-Krasovskii functional which uses the information on the lower bound of the delay sufficiently, a delay-dependent stability criterion is derived for the proposed UISGRNs model by using the free-weighting matrices method and convex combination technique. The conditions obtained here are expressed in terms of LMIs whose feasibility can be checked easily by MATLAB LMI control toolbox. In addition, three numerical examples are given to justify the obtained stability results
- …