an attack on a multisignature scheme

In this letter, we show that structured ElGamal-type multisignature scheme due to Burmester et al. is not secure if the adversary attacks key generation

Cryptanalysis of LU Decomposition-based Key Pre-distribution Scheme for Wireless Sensor Networks

S. J. Choi and H. Y. Youn proposed a key pre-distribution scheme for Wireless Sensor Networks based on LU decomposition of symmetric matrix, and later many researchers did works based on this scheme. Nevertheless, we find a mathematical relationship of L and U matrixes decomposed from symmetric matrix, by using which we can calculate one matrix from another regardless of their product -- the key matrix K. This relationship would profoundly harm the secure implementation of this decomposition scheme in the real world. In this paper, we first present and prove the mathematical theorem. Next we give samples to illustrate how to break the networks by using this theorem. Finally, we state the conclusion and some directions for improving the security of the key pre-distribution scheme

Yet another attack on a password authentication scheme based on quadratic residues with parameters unknown 1

In 1988, Harn, Laih and Huang proposed a password authentication scheme based on quadratic residues. However, in 1995, Chang, Wu and Laih pointed out that if the parameters d b a , , and l are known by the intruder, this scheme can be broken. In this paper, we presented another attack on the Harn-Laih-Huang scheme. In our attack, it doesn’t need to know the parameters and it is more efficient than the Chang-Wu-Laih attack

Optimal Multiple Assignments with (m,m)-Scheme for General Access Structures

Given the number n of the participants, one can solve an integer programming on 2^n variables to construct an optimal multiple assignment with threshold schemes for general access structure. In this paper, we focus on finding optimal multiple assignments with (m,m)-schemes. We prove that most of the variables in the corresponding integer programming take the value of 0, while the remaining variables take the values of either 0 or 1. We also show that given a complete access structure, an optimal scheme may be obtaineddirectly from the scheme by Ito, Saito, and Nishizeki (Secret sharing scheme realizeing any access structure, in Globecom 1987)

Methanol extract of Inonotus obliquus improves type 2 diabetes mellitus through modifying intestinal flora

Type 2 diabetes mellitus (T2DM) poses a significant risk to human health. Previous research demonstrated that Inonotus obliquus possesses good hypolipidemic, anti-inflammatory, and anti-tumor properties. In this research, we aim to investigate the potential treatment outcomes of Inonotus obliquus for T2DM and discuss its favourable influences on the intestinal flora. The chemical composition of Inonotus obliquus methanol extracts (IO) was analyzed by ultra-high-performance liquid chromatography-Q extractive-mass spectrometry. IO significantly improved the blood glucose level, blood lipid level, and inflammatory factor level in T2DM mice, and effectively alleviated the morphological changes of colon, liver and renal. Acetic acid, propionic acid, and butyric acid levels in the feces of the IO group were restored. 16S rRNA gene sequencing revealed that the intestinal flora composition of mice in the IO group was significantly modulated. Inonotus obliquus showed significant hypoglycemic and hypolipidemic effects with evident anti-inflammatory activity and improved the morphological structure of various organs and cells. Inonotus obliquus increased the levels of short-chain fatty acids in the environment by increasing the population of certain bacteria that produce acid, such as Alistipes and Akkermansia, which are beneficial to improve intestinal flora disorders and maintain intestinal flora homeostasis. Meanwhile, Inonotus obliquus further alleviated T2DM symptoms in db/db mice by down-regulating the high number of microorganisms that are dangerous, such as Proteobacteria and Rikenellaceae_RC9_gut_group and up-regulating the abundance of beneficial bacteria such as Odoribacter and Rikenella. Therefore, this study provides a new perspective for the treatment of T2DM by demonstrating that drug and food homologous active substances could relieve inflammation via regulating intestinal flora

Prognostic value of N-terminal Pro–B-Type natriuretic peptide in patients with intermediate coronary lesions

BackgroundThe optimal treatment strategy for patients with coronary intermediate lesions, defined as diameter stenosis of 50–70%, remains a great challenge for cardiologists. Identification of potential biomarkers predictive of major adverse cardiovascular events (MACEs) risk may assist in risk stratification and clinical decision.MethodsA total of 1,187 patients with intermediate coronary lesions and available N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were enrolled in the current study. A baseline NT-proBNP level was obtained. The primary endpoint was defined as MACEs, the composite endpoint of all-cause death and non-fatal myocardial infarction. A multivariate Cox regression model was used to explore the association between NT-proBNP level and MACE risk.ResultsThe mean age of the study cohort was 59.2 years. A total of 68 patients experienced MACE during a median follow-up of 6.1 years. Restricted cubic spline analysis delineated a linear relationship between the baseline NT-proBNP level and MACE risk. Both univariate and multivariate analyses demonstrated that an increased NT-proBNP level was associated with an increased risk of MACE [adjusted hazard ratio (HR) per doubling: 1.412, 95% confidence interval (CI): 1.022–1.952, p = 0.0365]. This association remains consistent in clinical meaningful subgroups according to age, sex, body mass index (BMI), and diabetes.ConclusionAn increased NT-proBNP level is associated with an increased risk of MACE in patients with intermediate coronary lesions and may serve as the potential biomarker for risk stratification and treatment decision guidance

Capillary liquid chromatography and mass spectrometry study of biological molecules.

In this work, packed capillary liquid chromatographic separation methods including affinity chromatography have been developed and interfaced to an ion trap storage/reflectron time-of-flight mass spectrometer (IT/reTOF MS). The combination of the non-scanning property of the time-of-flight mass analyzer and the ion signal integration capability of the ion trap provide rapid and sensitive full-mass range detection. The use of capillary LC has been shown to provide a substantially improved detection limit over conventional LC. Also, the use of mass spectrometry detection in combination with capillary LC provided additional qualitative information by indicating the analyte molecular weight with its retention time and also increased the resolving power of this system by clearly identifying co-eluting components. This method was used in rapid identification of proteins in complex cell extracts and peptide mapping, in the location of protein post-translational modifications, in characterization of proteins in different bacterial species where bacteria can be differentiated to the species level, and in elucidation of the metabolism of therapeutic peptides without the necessity of radiolabels. The method developed herein has proved to be an effective and sensitive approach when analytes are present at low levels in complex biological systems and when it is difficult to isolate each target protein. The IT/reTOF MS has proved to be a rapid and sensitive mass detector for capillary separations of biological samples.Ph.D.Analytical chemistryPure SciencesUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/131584/2/9910034.pd