History-Free Sequential Aggregate Signatures from Generic Trapdoor Functions

A sequential aggregate signature (SAS) scheme allows multiple users to sequentially combine their respective signatures in order to reduce communication costs. Historically, early proposals required the use of trapdoor permutation (e.g., RSA). In recent years, a number of attempts have been made to extend SAS schemes to post-quantum assumptions. Many post-quantum signatures have been proposed in the hash-and-sign paradigm, which requires the use of trapdoor functions and appears to be an ideal candidate for sequential aggregation attempts. However, the hardness in achieving post-quantum one-way permutations makes it difficult to obtain similarly general constructions. Direct attempts at generalizing permutation-based schemes have been proposed, but they either lack formal security or require additional properties on the trapdoor function, which are typically not available for multivariate or code-based functions. In this paper, we propose a history-free sequential aggregate signature based on generic trapdoor functions, generalizing existing techniques. We prove the security of our scheme in the random oracle model by adopting the probabilistic hash-and-sign with retry paradigm, and we instantiate our construction with three post-quantum schemes, comparing their compression capabilities. Finally, we discuss how direct extensions of permutation-based SAS schemes are not possible without additional properties, showing the insecurity of two existing multivariate schemes when instantiated with Unbalanced Oil and Vinegar

Group Factorisation for Smaller Signatures from Cryptographic Group Actions

Cryptographic group actions have gained significant attention in recent years for their application on post-quantum Sigma protocols and digital signatures. In NIST\u27s recent additional call for post-quantum signatures, three relevant proposals are based on group actions: LESS, MEDS, and ALTEQ. This work explores signature optimisations leveraging a group\u27s factorisation. We show that if the group admits a factorisation as a semidirect product of subgroups, the group action can be restricted on a quotient space under the equivalence relation induced by the factorisation. If the relation is efficiently decidable, we show that it is possible to construct an equivalent Sigma protocol for a relationship that depends only on one of the subgroups. Moreover, if a special class of representative of the quotient space is efficiently computable via a canonical form, the restricted action is effective and does not incur in security loss. Finally, we apply these techniques to the group actions underlying LESS and MEDS, showing how they will affect the length of signatures and public keys

MAYO: Optimized Implementation with Revised Parameters for ARMv7-M

We present an optimized constant-time implementation of the MAYO signature scheme on ARMv7-M. MAYO is a novel multivariate proposal based on the trapdoor function of the Unbalanced Oil and Vinegar scheme. Our implementation builds on existing techniques for UOV-based schemes and introduces a new approach for evaluating the polar forms of quadratic maps. We modify MAYO\u27s original parameters to achieve greater benefits from the proposed optimizations, resulting in slightly larger keys and shorter signatures for the same level of security. We evaluate the optimized implementation with the new parameters on the STM32H753ZIT6 microcontroller and measure its performance for the signing and verification procedures. At NIST security level I, signing requires approximately 43M cycles, and verification requires approximately 6M cycles. Both are 2.6 times faster than the results obtained from the original parameters

A Framework for Group Action-Based Multi-Signatures and Applications to LESS, MEDS, and ALTEQ

A multi-signature scheme allows a list of signers to sign a common message. They are widely used in scenarios where the same message must be signed and transmitted by $N$ users, and, instead of concatenating $N$ individual signatures, employing a multi-signature can reduce the data to be sent. In recent years there have been numerous practical proposals in the discrete logarithm setting, such as MuSig2 (CRYPTO\u2721) for the Schnorr signature. Recently, these attempts have been extended to post-quantum assumptions, with lattice-based proposals such as MuSig-L (CRYPTO\u2722). Given the growth of group action-based signatures, a natural question is whether a multi-signature can be built on the same models. In this work, we present the first construction of such a primitive relying on group action assumptions. We obtain a 3-round scheme achieving concurrent security in the ROM. Moreover, we instantiate it using the three candidates to the additional post-quantum NIST\u27s call, namely LESS, MEDS and ALTEQ, obtaining a good compression rate for different parameters sets

History vs. legend: Retracing invasion and spread of Oxalis pes-caprae L. in Europe and the Mediterranean area

Oxalis pes-caprae L. is a South African geophyte that behaves as an invasive in the eurimediterranean area. According to a long-established hypothesis, O. pes-caprae may have invaded Europe and the Mediterranean area starting from a single plant introduced in the Botanical Garden of Malta at the beginning of the 19th century. The aim of this work was to test this hypothesis, to track the arrival of O. pes-caprae in different countries of the Euro-Mediterranean area and to understand the pathways of spreading and particularly its starting point(s). Historical data attesting the presence of the plant in the whole Euro-Mediterranean region were collected from different sources: herbarium specimens, Floras and other botanical papers, plant lists of gardens, catalogs of plant nurseries and plant dealers. First records of the plant (both cultivated and wild) for each Territorial Unit (3rd level of NUTS) were selected and used to draw up a diachronic map and an animated graphic. Both documents clearly show that oldest records are scattered throughout the whole area, proving that the plant arrived in Europe and in the Mediterranean region more times independently and that its spreading started in different times from several different centers of invasion. Botanical gardens and other public or private gardens, nurseries and plant dealers, and above all seaside towns and harbors seemingly played a strategic role as a source of either intentional and unintentional introduction or spread. A geographic profiling analysis was performed to analyse the data. We used also techniques (Silhouette, Kmeans and Voronoi tessellation) capable of verifying the presence of more than one independent clusters of data on the basis of their geographical distribution. Microsatellites were employed for a preliminary analysis of genetic variation in the Mediterranean. Even if the sampling was insufficient, particularly among the populations of the original area, our data supported three main groups of populations, one of them corresponding to the central group of populations identified by GP analysis, and the other two corresponding, respectively, to the western and the eastern cluster of data. The most probable areas of origin of the invasion in the three clusters of observations are characterized by the presence of localities where the invasive plant was cultivated, with the exception of the Iberian cluster of observation where the observations in the field predate the data about known cultivation localities. Alternative possible reasons are also suggested, to explain the current prevalence of pentaploid short-styled plants in the Euro-Mediterranean area

Probiotics May Improve Serum Folate Availability in Pregnant Women: A Pilot Study

BACKGROUND: Probiotics are living microorganisms that confer a health benefit when administered in adequate amounts. There is evidence in the current literature about the importance of probiotic use in pregnancy. The early supplementation of probiotics in the perinatal and postnatal periods seems to have a positive impact on the overall mother’s health and future health of infants. AIM: Our pilot study aimed to test the ability of specific probiotics strains in combination with the kiwi-unique enzyme actinidin to improve the availability of folic acid in 20 pregnant women. METHODS: We investigate 20 pregnant women in early (4–10 weeks) (6 patients), intermedium (11–20 weeks) (6 patients), and late (21–30 weeks) (8 patients) pregnancy. RESULTS: Our findings show that the tested formula promotes increased concentration of serum folate in women’s blood and contributes to the control of blood sugar and body weight, regardless of the gestational period (early, intermediate or late). CONCLUSIONS: Our data support the main results reported in the scientific literature about the importance of probiotics intake in pregnancy

Efficacy of Sea Salt-Based Mouthwash and Xylitol in Improving Oral Hygiene among Adolescent Population: A Pilot Study

The scientific community has definitely demonstrated the importance of the use of mouthwash in daily oral hygiene. In our pilot study, we tested the effectiveness of a novel mouth rinse containing sea salt, xylitol, and lysozyme. Streptococcus mutans (S. mutans) growth, and plaque index in adolescent patients aged 14–17 years, were observed. The bacterial load was investigated by in vitro microbiological analysis; the plaque index was assessed through the O’Leary’s Plaque Control Record (PCR). The study has shown that the use of a sea salt-based mouthwash in daily oral hygiene reduces the bacterial levels of S. mutans (p < 0.01) linked to the combined action of xylitol and lysozyme, together with the action of sea salt. Our preliminary data confirm and improve the main results reported in the scientific literature on the importance of the use of xylitol, lysozyme, and sea salt in oral health

Isoprostanoids in clinical and experimental neurological disease models

Isoprostanoids are a large family of compounds derived from non-enzymatic oxidation of polyunsaturated fatty acids (PUFAs). Unlike other oxidative stress biomarkers, they provide unique information on the precursor of the targeted PUFA. Although they were discovered about a quarter of century ago, the knowledge on the role of key isoprostanoids in the pathogenesis of experimental and human disease models remains limited. This is mainly due to the limited availability of highly purified molecules to be used as a reference standard in the identification of biological samples. The accurate knowledge on their biological relevance is the critical step that could be translated from some mere technical/industrial advances into a reliable biological disease marker which is helpful in deciphering the oxidative stress puzzle related to neurological disorders. Recent research indicates the value of isoprostanoids in predicting the clinical presentation and evolution of the neurological diseases. This review focuses on the relevance of isoprostanoids as mediators and potential biomarkers in neurological diseases, a heterogeneous family ranging from rare brain diseases to major health conditions that could have worldwide socioeconomic impact in the health sector. The current challenge is to identify the preferential biochemical pathways that actually follow the oxidative reactions in the neurological diseases and the consequence of the specific isoprostanes in the underlying pathogenic mechanisms

Persistent Unresolved Inflammation in the Mecp2

Rett syndrome (RTT) is a rare neurodevelopmental disorder usually caused by mutations in the X-linked gene methyl-CpG-binding protein 2 (MECP2). Several Mecp2 mutant mouse lines have been developed recapitulating part of the clinical features. In particular, Mecp2-308 female heterozygous mice, bearing a truncating mutation, are a validated model of the disease. While recent data suggest a role for inflammation in RTT, little information on the inflammatory status in murine models of the disease is available. Here, we investigated the inflammatory status by proteomic 2-DE/MALDI-ToF/ToF analyses in symptomatic Mecp2-308 female mice. Ten differentially expressed proteins were evidenced in the Mecp2-308 mutated plasma proteome. In particular, 5 positive acute-phase response (APR) proteins increased (i.e., kininogen-1, alpha-fetoprotein, mannose-binding protein C, alpha-1-antitrypsin, and alpha-2-macroglobulin), and 3 negative APR reactants were decreased (i.e., serotransferrin, albumin, and apolipoprotein A1). CD5 antigen-like and vitamin D-binding protein, two proteins strictly related to inflammation, were also changed. These results indicate for the first time a persistent unresolved inflammation of unknown origin in the Mecp2-308 mouse model