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A transient fault-based collision attack always requires to inject fault multiple times. We present the first attack that uses collision information caused by a persistent fault in the substitution box (S-box) to recover the entire 128-bit key of the advanced encryption standard (AES). Moreover, a relatively relaxed fault model is required; i.e., the attacker does not know any information about the position, the length (i.e., the number of bytes), or the value of the injected fault. At most, 4096 chosen plaintexts are required for a persistent fault-based collision attack (PFCA), and the computational complexity is $O(2^{23})$ in the worst case in the single-byte fault setting. A filtering algorithm is presented in the multibyte fault setting, and we theoretically prove that the complexity can be reduced to $O(2^{12})$ in more than half of cases if the number of collision ciphertexts follows a uniform distribution. In addition, PFCAs against a software implementation of AES are simulated on a laptop, and the results show that the success probability of the attack either with online key searching or with offline key searching approaches 100%. In particular, more than 97% of all experiments output the right key with complexity $O(2^{12})$ in the multibyte fault setting. Therefore, the attack is more efficient in this scenario. Furthermore, the attack works on an AES implementation protected by Boolean masking. Finally, PFCAs against AES implementations separately protected by two widely used countermeasures—the inverse S-box and the parity-1 matrix—are performed. The experimental results illustrate that only a 10-round protection using the first method can completely defeat the attack.

Objective To investigate the efficacy and mechanism of c-Jun N-terminal kinase (JNK) in boosting survival of oxygen glucose deprivation (OGD) rat neurons. Methods The cortex neurons from fetal rats were primarily cultured to prepare a model of OGD neurons in vitro, and the characteristic endpoints were filtered to intervene with JNK inducer anisomycin (AN), respectively. The cells were randomly divided into control group, solvent control group (a same volume of solvent DMSO was added into the culture medium of the OGD neuron), AN group (OGD neurons were treated with JNK inducer AN for 5 hours at the end of OGD). After that, Western blotting and immunofluorescence cytometry were respectively performed to detect the protein expressions in OGD neurons, including beclin 1, microtubule-associated protein 1 light chain 3 (LC3), B cell lymphoma 2 (Bcl2), caspase-3, P62, ubiquitin, cathepsin B and lysosomal associated membrane protein 1 (LAMP1). The cell activity was evaluated by CCK-8 assay, and the axon length was measured by IPP software. Results Activation of JNK significantly promoted the expressions of beclin 1, LC3, and Bcl2, and markedly reduced the content of beclin 1-Bcl2 complex and attenuated the expressions of P62 and ubiquitin. Meanwhile, the expressions of cathepsin B and LAMP1 were not obviously altered. In this way, the survival rate of OGD neurons was improved. Conclusion Activation of JNK exerts a neuroprotective effect by facilitating dissociation of beclin 1-Bcl2 and inducing a switch from apoptosis to autophagy in OGD neurons.

Patient satisfaction studies have gained more and more attention, and there are many patient satisfaction studies. These studies assume that patients were selected randomly and independently, but patient satisfaction surveys are described as a multistage or hierarchically structured sample. Thus, there is a need to conduct a hierarchical linear model (HLM) analysis with a large number of hospitals. This study utilized an HLM to investigate both the individual patient-level effect on the overall satisfaction rating and the effect of hospital characteristics on the combining process of patient’s overall satisfaction rating. This study used patient satisfaction data collected from 100 hospitals with the sample size of 85 766. The hospital-level characteristics include total expense per personnel, payroll expense per personnel, number of staffed beds per personnel, and number of admission per personnel. This study found that hospital characteristics influence overall rating of the hospital through the doctor, staff, and room attributes. When considering the complex nature of the overall patient rating process of hospitals, it makes more sense to analyze hospital characteristics that are interacting with attributes rather than treat hospital characteristics as independent of these factors.

The construction of multivariate models for analyzing family data can be challenging due to the various dependencies between family members. These models typically have parameters that are subject to intricate and stringent constraints, which make it more difficult to arrive at a proper estimation of these model parameters. Recently, vines and pair-copula constructions have been utilized in order to simplify construction of multivariate models for both continuous and discrete data. The pair-copula models break down the hierarchy of dependence into vines and employ bivariate or pair-copulas as “building bricks” to generate appropriate multivariate distributions. This paper discusses pair-copula methods to model the convoluted dependence structure and proposes using a C-Vine type copula to model the dependence among family members. Analysis of actual, real-world family data is presented to illustrate our models and estimation procedures.

We used a logistic regression model to analyze data from routinely collected student evaluation of teaching from 2,211 nursing students over 8 semesters. The results showed that not all aspects of teaching are equally influential in their effects on students' overall rating of instructors' teaching as excellent. Influential aspects include motivation, individual assistance, presentation of concepts, environment, and practical application. The most influential evaluation aspect is motivation.

Styrene-butane-styrene (SBS) modified bitumen has been widely applied in pavement engineering due to its excellent cracking and rutting resistance. However, there are workability concerns due to its higher viscosity compared to virgin bitumen. Conventional Warm Mix Asphalt (WMA) technologies including surfactants and foaming additives have been successfully applied to SBS bitumen. This study attempts to evaluate whether compound WMA technologies (e.g., the foaming procedure and the surfactant additive) can bring further engineering and environmental benefits. Surfactant additive solution (Evotherm-DAT) was used as a novel foaming agent to foam SBS bitumen instead of water during the foaming process. A series of chemical, foaming and rheological tests were conducted for performance evaluations on the surfactant additive (SA) foamed SBS bitumen. It was found that a limited chemical reaction happens among SA and SBS bitumen. Besides, surfactant used as the novel foaming agent can bring positive effects on foaming behaviors. Furthermore, SA foamed SBS bitumen presents better workability, rutting and fatigue resistance. Finally, it is proven that the compound WMA fashion using surfactant additive and foaming procedure is feasible on SBS bitumen.

Residual waste toner (WT), which is abundantly generating with modern industry, is a potential green resource that can be used as an asphalt modifier for better engineering performance and cost-saving. This study is conducted to comprehensively evaluate the feasibility of using WT as an asphalt modifier considering various rheological properties of the modified binder. Four different WT modified asphalt are prepared (with WT contents of 3%, 6%, 9%, and 12%). The properties of the modified binder were investigated through a series of rheological tests including the conventional binder specification tests (penetration, softening point, ductility, and flash point), multiple stress creep recovery (MSCR), and Bending Beam Rheometer (BBR) tests. Testing results indicated that the incorporation of WT can improve the rheological properties of the asphalt binders at low and high temperatures regardless of the WT contents. Besides, WT was shown a positive impact on fracture and bonding performances. It is noted that asphalt binders containing up to 12% of WT had a significant improvement on high-temperature, intermediate temperature fracture, low-temperature cracking, and moisture sensitivity properties. In the end, the present research shows the residual WT as a value-added modifier is a promising solution with both environmental and engineering merits.

Archimedean copulas are commonly used in a wide range of statistical models due to their simplicity, manageable analytical expressions, rich choices of generator functions, and other workable properties. However, the exchangeable dependence structure inherent to Archimedean copulas limits its application to familial data, where the dependence among family members is often different. When response variables are binary, modeling the familial associations becomes more challenging due to the stringent constraints imposed on the dependence parameters. This paper proposes hierarchical Archimedean copulas to account for the natural hierarchical dependence structure in familial data and addresses the details in the modeling of binary familial data and the inference based on maximum likelihood estimate. An example showing the flexibility of this powerful tool is also presented with possible extension to other similar studies.

Modeling binary familial data has been a challenging task due to the dependence among family members and the constraints imposed on the joint probability distribution of the binary responses. This paper investigates some useful familial dependence structures and proposes analyzing binary familial data using Gaussian copula model. Advantages of this approach are discussed as well as some computational details. An numerical example is also presented with an aim to show the capability of Gaussian copula model in more sophisticated data analysis.

Most patient satisfaction studies put an emphasis on finding key drivers (attribute) to increase overall patient satisfaction. However, it is not clear how much health care managers need to improve certain attributes to attain the target overall patient satisfaction level. The study aims at finding not only what attributes, but also how much these attributes need to be improved to attain the target levels of patient satisfaction. The study uses an ordinal logistic regression model to analyze attribute reactions to salient drivers. This approach would significantly enhance health care managers' capabilities to develop a strategic plan to improve their patient satisfaction levels.

While univariate instances of binomial data are readily handled with generalized linear models, cases of multivariate or repeated measure binomial data are complicated by the possibility of correlated responses. Likelihood-based estimation can be applied by using mixture distribution models, though this approach can present computational challenges. The logistic transformation can be used to bypass these concerns and allow for alternative estimating procedures. One popular alternative is the generalized estimating equation (GEE) method, though systematic errors can lead to infeasible correlation estimates or nonconvergence problems. Our approach is the coupling of quasileast squares (QLSs) method with a rarely used matrix factorization, which achieves a simplified estimation platform—as compared to the mixture model approach—and does not suffer from the convergence problems in GEE method. A noncontrived example is provided that shows the mechanical breakdown of GEE using several statistical software packages and highlights the usefulness of the QLS approach.

The probit function is an alternative transformation to the logistic function in the analysis of binary data. However, use of the probit function is prohibitively complicated for cases of multivariate or repeated-measure binary responses, as integrations involving the multivariate normal distribution can be difficult to compute. In this paper, we propose an alternative form to stochastically represent random variables in the case of familial binary data that simplifies calculation of the multivariate normal integrals involved in the probit link. We provide examples of these stochastic representations for one- and two-parent families, and compare the performance of this methodology with that of moment estimators by calculating asymptotic relative efficiencies and through a real-life data example. Particular attention is paid to analyzing the properties of regression parameter estimates from these two methods with respect to the feasible ranges of the correlation parameters.

Since Mycobacterium bovis bacillus Calmette-Guerin strain (BCG) fails to protect adults from pulmonary tuberculosis (TB), there is an urgent need for developing a new vaccine. In this study, we constructed a novel recombinant BCG strain (rBCG) expressing human granulocyte macrophage colony-stimulating factor (GM-CSF) and the 6 kDa early secretory antigenic target (ESAT6) of Mycobacterium tuberculosis, named rBCG:GE (expressing GMCSF-ESAT6 complex), and evaluated the immunogenicity of the construct in BALB/c mice. Our results indicated that the rBCG:GE was able to induce higher titer of antibody than the conventional BCG, the rBCG:G (expressing GM-CSF) and the rBCG:E (expressing ESAT6). Moreover, the rBCG:GE also elicited a longer-lasting and stronger Th1 cellular immune responses than the other groups, which was confirmed by the incremental proliferation of splenocytes, the increased percentages of CD4(+) and CD8(+) T cells of spleen, the elevated level of interferon-γ in splenocyte culture after tuberculin-purified protein derivative stimulation, and the increased concentration of GM-CSF in serum. The data presented here suggested the possibility that the recombinant BCG:GE might be a good vaccine candidate to TB.

The decomposition of a matrix as a product of a lower triangular with ones on the diagonal and an upper triangular matrix is useful for solving systems of linear equations. For a given non singular matrix, this type of decomposition is unique and algorithms exist to obtain the two factors. However, in certain problems the factorization of the inverse matrix may be of interest. This note presents an algorithm for factoring the inverse matrix using simple operations of elements from the original matrix. As examples, we give factorizations for several well-known and widely used correlation matrices. The usefulness and practicality of these factorizations are provided in an application of statistical modeling using unbiased estimating equations.

Early secretory antigen target 6 (ESAT-6) is a dominant target for cell-mediated immunity in the early phase of tuberculosis (TB) in patients with TB, causing T-cell proliferation and gamma interferon (IFN-γ) production, which has been considered to be a protective antigen that can be used for future vaccine development. Ag85A is the most essential component for bacterial survival within macrophages and has been used in numerous vaccine preparations, which can induce strong cellular immune responses. In this study, we constructed a new recombinant bacilli Calmette-Guerin (BCG) strain (rBCG-AE) that could express fusion protein Ag85A-ESAT-6 of Mycobacterium tuberculosis and evaluated its immunogenicity in BALB/c mice. There was no evidence for increased virulence of this rBCG. Our experiments illustrated that the rBCG-AE was able to induce higher titer of antibody and elicit more long-lasting and stronger Th1 type cellular immune responses than the parental BCG strain, or rBCG-A (expressing Ag85A) strain, or rBCG-E (expressing ESAT-6) strain, which are characterized by the strong antibody response, the proliferation rate of splenocytes, the ratio of CD4(+) T and CD8(+) T cells stimulated by tuberculin-purified protein derivative and elevated levels of IFN-γ in antigen-stimulated splenocyte cultures. The results show that rBCG-AE is an improved TB vaccine for further study.

Familial binary data occur in a wide range of scientific investigations. Numerous measures of association have been proposed in the literature for the study of intra-family dependence of the binary variables. These measures include correlations, odd ratios, kappa statistics, and relative risks. We study the permissible ranges of these measures of association such that a joint distribution exists for the familial binary variables. Our results are useful for developing efficient estimation methods for the measures of association.

To obtain a vaccine to defend from dormancy Mycobacterium tuberculosis, we constructed the recombinant Bacilli Calmette-Guérin (BCG) vaccine with Rv3133c encoding dormancy-correlated transcriptional regulatory protein DosR in Mycobacterium tuberculosis as a target gene, and evaluated its immunogenicity in BALB/c mice. In this study, we constructed the recombinant plasmids of rpMV361-Rv3133c using gene colon technology. We then transformed BCG strains with above-mentioned plasmids to obtain recombinant vaccine of rBCG-Rv3133c. We used the rBCG strains successfully constructed to vaccinate in BALB/c mice. 30d and 180d after immunization, the specific antibody titers were determined to investigate humoral responses induced by recombinant vaccine. We detected changes of splenocyte subsets of CD4+T, CD8+ T cells and cytokine of IFN-gamma secreted by splenocytes for evaluation of cellular immune responses. The results showed that the rBCG-Rv3133c was able to induce higher levels of antibody titer, stronger proliferative responses and higher IFN-gamma production comparing with BCG vaccine. The results also suggested that this recombinant vaccine was a more efficacious tuberculosis vaccine for further study.

ESAT-6 protein of Mycobacterium tuberculosis is absent in Mycobacterium bovis BCG and Mycobacterium microti and has been demonstrated to stimulate strong cell-mediated immunity. IL-12 can play crucial roles in regulating IFN-γ production and Th1 effectors production. In this study, we constructed three rBCG vaccines that could express proteins of human IL-12p70 and/or ESAT-6 and evaluated their immunogenicity and protective efficacy in mice. Our experiments illustrated that the rBCG-IE (expressing a fusion protein of human IL-12p70 and ESAT-6) was capable of inducing stronger Th1 type cell-mediated immune responses than conventional BCG, or rBCG-I (expressing human IL-12p70), or rBCG-E (expressing ESAT-6). However, the results of protective experiments showed that rBCG-IE could only confer similar and even lower protective efficacy against M. tuberculosis H37Rv infection compared with BCG vaccine.

Since Mycobacterium bovis bacillus Calmette-Guerin strain (BCG) fails to protect adults from pulmonary tuberculosis (TB), there is an urgent need for developing a new vaccine. In this study, we constructed a novel recombinant BCG strain (rBCG) expressing human granulocyte macrophage colony-stimulating factor (GM-CSF) and the 6 kDa early secretory antigenic target (ESAT6) of Mycobacterium tuberculosis, named rBCG:GE (expressing GMCSF-ESAT6 complex), and evaluated the immunogenicity of the construct in BALB/c mice. Our results indicated that the rBCG:GE was able to induce higher titer of antibody than the conventional BCG, the rBCG:G (expressing GM-CSF) and the rBCG:E (expressing ESAT6). Moreover, the rBCG:GE also elicited a longer-lasting and stronger Th1 cellular immune responses than the other groups, which was confirmed by the incremental proliferation of splenocytes, the increased percentages of CD4(+) and CD8(+) T cells of spleen, the elevated level of interferon-γ in splenocyte culture after tuberculin-purified protein derivative stimulation, and the increased concentration of GM-CSF in serum. The data presented here suggested the possibility that the recombinant BCG:GE might be a good vaccine candidate to TB.

To establish an alcoholic liver disease model in rats to study the effect of Hepcidin on the development of alcoholic liver disease.Fourty SD rats were randomly divided into 2 groups, 20 for each group. Saline [10 mL/(kg x d)] and 56% ethano infusion [10 mL/(kg x d)] were given orally to the rats for 12 weeks for the control and experimental group, respectively. The serum ALT, AST, and iron, and the superoxide dismutase (SOD) activity and malonaldehyde (MDA) content in the hepatic tissue were determined. RT-PCR was employed to examine the expression of Hepcidin mRNA in the liver. The histopathological changes of the liver tissues were examined through HE, Sudan IV and immunohistochemical stainings.The rats in the experimental group had greater serum ALT, AST and iron, and decreased SOD activity and increased MDA activity than those in the control group (P0.01). The rats in the experimental group had enlarged livers, with rough surface and grey-yellow color. The rats in the experimental group had more local hepatocellular necrosis, inflammatory cells, and large fat droplets, and larger red tangerine staining sectors in the livers than those in the control group (P0.05). Higher positive expressions of TNF-alpha and IL-6 in the liver tissues were found in the experimental group than in the control group (P0.01). The rats in the experimental group had lower levels of mRNA of Hepcidin than those in the control group (P0.01).The rats with alcoholic livers have increased expression of TNF-alpha and IL-6 and decreased expression of Hepcidin in the liver tissues.