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Le pyoderma gangrenosum (PG) est une dermatose neutrophilique non infectieuse rare souvent méconnue. Il se présente généralement par des ulcérations cutanées inflammatoires, très douloureuses et d'évolution rapide. Il est fréquemment retrouvé dans un contexte de néoplasie, de pathologies inflammatoires digestives, rhumatologiques et/ou hématologiques. Son diagnostic est très souvent tardif après de multiples échecs thérapeutiques. Nous rapportons un cas de pyoderma gangrenosum dont le diagnostic n'a pas été criant. Un patient a été admis dans notre service pour une lésion dermatologique persistante et d'évolution défavorable malgré les débridements et l'administration d'antibiotiques. Il était suivi pour un cancer de la prostate, une hypertension artérielle et un asthme. Du fait des anomalies biologiques observées telles qu'une hyperleucocytose à polynucléaires neutrophiles avec myélémie à myélocytes et métamyélocytes, sans blastose sanguine et une anémie normochrome normocytaire, une leucémie myéloïde chronique a été évoquée chez ce patient. Elle a par la suite été infirmée devant les différents examens complémentaires non concluants. C'est ainsi que le diagnostic de PG a été évoqué et confirmé à l'examen anatomopathologique montrant un aspect histopathologique d'un tissu de granulation concordant avec un pyoderma gangrenosum et une absence de signe histologique de malignité. L'institution d'un traitement à base de corticothérapie a abouti à la guérison.

NTRU is one of the first public key cryptosystems not based on factorization or discrete logarithmic problems and is also considered secure even against quantum computer attacks. In 2011, Stehle and Steinfeld proposed a variant of the classical NTRU that is IND-CPA secure but for the key generation algorithm, they use Gaussian distribution with a large standard deviation to prove the uniformity of the public key by assuming the hardness of Ring Learning With Error (Ring-LWE) problem. In this paper, we present two variants of NTRUEncrypt called BI-NTRU-Product and BI-NTRU-LPR which are IND-CPA secure assuming the hardness of Ring-LWE problem. We also show how one can design an IND-CCA2 secure key encapsulation mechanism from our encryption schemes by using a variant of the Fujisaki-Okamoto Transformation (CRYPTO 1999 and Journal of Cryptology 2013).

Let \(I=\langle f_1,\ldots ,f_s\rangle \) be an ideal of \(R=\mathbb {Z}[x_1,\ldots ,x_n]\). We introduce in this paper the concept of \(\mathbb {Z}-\)ideal \(\mathbb {Z}(I)\) of I which is a proper ideal of R and we propose a technique for computing a weak Grobner basis for \(\mathbb {Z}(I)\). This result is central and leads to the computation of a minimal free resolution for \(\mathbb {Z}(I)\) as an \(R-\)module.

OBJECTIVE The prevalence of type 2 diabetes (T2D) is rapidly increasing in sub-Saharan Africa, where sickle cell trait (SCT) is also frequent. Although SCT is generally considered a benign condition, evidence suggests that SCT could exaggerate vascular dysfunction in T2D. However, it remains unclear whether SCT could increase the risk of the development of T2D complications. Therefore, this study was conducted to determine whether T2D complications were more prevalent among Senegalese individuals with SCT and T2D than among those with T2D only. RESEARCH DESIGN AND METHODS Rates of hypertension, retinopathy, peripheral neuropathy, peripheral artery disease, and impaired renal function as well as arterial stiffness, blood rheology, and concentrations of plasma advanced glycation end products (AGEs) and cytokines were compared between groups of Senegalese individuals with combined SCT and T2D (T2D-SCT) (n = 60), T2D (n = 52), SCT (n = 53), and neither T2D nor SCT (control) (n = 56). Human aortic endothelial cell (HAEC) expression of inflammatory and adhesion factors was measured after treatment with tumor necrosis factor-α and subjects’ plasma. Effects of AGE inhibition or tiron on HAEC expression of E-selectin were measured. RESULTS Retinopathy, hypertension, and reduced renal function were more prevalent, and arterial stiffness, blood viscosity at high shear rates, and thixotropic index were higher, in the T2D-SCT group compared with the other groups. Multivariable analysis showed that plasma AGE concentration was significantly associated with arterial stiffness. E-selectin expression was elevated in HAECs treated with T2D-SCT plasma compared with the other groups, but AGE inhibition reversed this. CONCLUSIONS SCT could potentially augment the risk of the development of T2D-related complications, including retinopathy, nephropathy, and hypertension.

Introduction : L'hyperthyroidie de l'enfant semble rare et constitue un probleme de par son retentissement psychosomatique. L’objectif etait de faire le point sur ses aspects epidemiologiques et diagnostiques chez l’enfant a Dakar. Methodes : Il s'agissait d'une etude multicentrique, descriptive sur 15 ans. Etaient analyses les aspects epidemiologiques, cliniques et etiologiques. Resultats : 239 patients selectionnes avec une prevalence de 2.4%, un sex ratio (H/F) de 0.36, un âge moyen de 10.8 ans. A l'inclusion, il s'agissait d'un aine de famille (26.3%), d'une croissance avancee (36.9%), retardee (12.5%), d'une corpulence insuffisante (40.1%). L'etiologie etait la maladie de Basedow dans 90.3% avec un facteur psychoaffectif dans 22.1%. Sur le plan clinique, predominaient la tachycardie (92.4%), le goitre (91.1%), l'exophtalmie (81.8%), l'amaigrissement (69.8%) avec cependant une enuresie (30.2%) et des manifestations psychiques (3.1%). Les manifestations cardiovasculaires et cutanees etaient positivement associees avec l'âge (p < 0.05). Le goitre etait associe au sexe feminin (p = 0.005), aux signes cardiovasculaires (p = 0.02), neuropsychiques (p = 0.03), cutanees (p = 0.03) et a la diarrhee (p = 0.03). La T4 libre etait correlee a l'âge (p = 0.007), la diarrhee (p = 0.021), l'anxiete (p = 0.024), la frequence cardiaque (p = 0.00) et la maladie de Basedow (p = 0.04). Plus le goitre etait volumineux, plus etait augmentee la T4 libre (p = 0.007). Conclusion : L'hyperthyroidie de l'enfant se differencie de celle de l'adulte par les facteurs d'induction, les perturbations sur la croissance et l'enuresie. L’âge et le sexe semble favoriser le tableau clinique de thyrotoxicose et les signes associes. Mots cles : Hyperthyroidie, enfant, Senegal

Feedback Shift Register (FSR) is generally the basic element of pseudo random generators used to generate cryptographic channel or set of sequences for encryption keys. This type of generator is widely used in stream cipher and communication systems such as C.D.M.A (Code Division Multiple Access), mobile communication systems, ranging and navigating systems, spread spectrum communication systems. The objective of the present paper is to propose a method for determining linear recurring sequences generating linear feedback shift register (LFSR) from primitive polynomials (and vice-versa). The linear recurring sequences facilitate the construction of maximum length LFSR. It also insists, in the last part, on the cryptographic security of LFSR and indicates some open problems in the area of nonlinear feedback shift registers (NLFSR) based pseudo random generators.

We propose two-sources randomness extractors over finite fields and on elliptic curves that can extract from two sources of information without consideration of other assumptions that the starting algorithmic assumptions with a competitive level of security. These functions have several applications. We propose here a description of a version of a Diffie-Hellman key exchange protocol and key extraction. Nous proposons des extracteurs d'aléas 2-sources sur les corps finis et sur les courbes elliptiques capables d'extraire à partir de plusieurs sources d'informations sans considération d'autres hypothèses que les hypothèses algorithmiques de départ avec un niveau de sécurité compétitif. Ces fonctions possèdent plusieurs applications. Nous proposons ici une version du protocole d'échange de clé Diffie-Hellman incluant la phase d'extraction.

This paper studies the task of two-sources randomness extractors for elliptic curves defined over finite fields K, where K can be a prime or a binary field. In fact, we introduce new constructions of functions over elliptic curves which take in input two random points from two different subgroups. In other words, for a given elliptic curve E defined over a finite field \(\mathbb {F}_q\) and two random points \(P \in \mathcal {P}\) and \(Q\in \mathcal {Q}\), where \(\mathcal {P}\) and \(\mathcal {Q}\) are two subgroups of \(E(\mathbb {F}_q)\), our function extracts the least significant bits of the abscissa of the point \(P\oplus Q\) when q is a large prime, and the k-first \(\mathbb {F}_p\) coefficients of the abscissa of the point \(P\oplus Q\) when \(q = p^n\), where p is a prime greater than 5. We show that the extracted bits are close to uniform.

In this work, we propose a method for computing noncommutative Grobner bases over a noetherian valuation ring. We have generalized the fundamental theorem on normal forms over an arbitrary ring. The classical method of dynamical commutative Grobner bases is generalized to Buchberger's algorithm over R = 𝒱 ⟨ x 1,…, x m ⟩, a free associative algebra with noncommuting variables, where 𝒱 = ℤ/nℤ and 𝒱 = ℤ. The proposed process generalizes previous known techniques for the computation of commutative Grobner bases over a naetherian valuation ring and/or noncommutative Grobner bases over a field.

In the article cited above, the first sentence in the Results section of the abstract had the name of the group …

This paper introduces a new public key cryptosystem based on two hard problems : the cube root extraction modulo a composite moduli (which is equivalent to the factorisation of the moduli) and the discrete logarithm problem. These two hard problems are combined during the key generation, encryption and decryption phases. By combining the IFP and the DLP we introduce a secure and efficient public key cryptosystem. To break the scheme, an adversary may solve the IFP and the DLP separately which is computationally infeasible. The key generation is a simple operation based on the discrete logarithm modulo a composite moduli. The encryption phase is based both on the cube root computation and the DLP. These operations are computationally efficient., Something was not correct in the paper

Copyright c � 2013 Abdoul Aziz Ciss and Djiby Sow. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

The main objective of this article is to study noncommutative Grobner bases over a divisible and annihilable ring (D-A ring). Such rings were introduced by Deepak Kapur and Yongyang Cai [4], and an algorithm for computing Grobner bases in the commutative case was also given. If I is an ideal of the associative algebra \(V \langle x_{1},\ldots,x_{n}\rangle = V \langle \overline{x}\rangle\) with non-commuting variables x1, …, x n over a valuation ring V, a method for computing a Grobner basis of I was proposed recently. This method solves the membership problem in I but does not allow to compute in the quotient ring \(V \langle \overline{x}\rangle /I\). We generalized the method of Kapur and Cai in the noncommutative case. Our method allows to compute in the quotient ring \(D\langle \overline{x}\rangle /I\), where D is a D-A ring. This new approach for Grobner basis over a D-A ring can have some applications in cryptography such as the study of the public key cryptosystem NTRU in \(\dfrac{\mathbb{Z}_{n}[i][X]} {\langle X^{2} - 1\rangle }\) where \(\mathbb{Z}_{n}[i]\) is a D-A ring.

Linear recurrences sequences are widely studied over fields rings and modules. In this paper, we introduce the notion of linear recurrence sequence over semirings. After investigating some basics properties, we give a characterization of linear recurrence sequence over zero-sum semirings.

Let R be a ring with identity. A right R-module M has the com- plete max-property if the maximal submodules of M are completely coindepen- dent (i.e., every maximal submodule of M does not contain the intersection of the other maximal submodules of M). A right R-module is said to be a good module provided every proper submodule of M containing Rad(M) is an intersection of maximal submodules of M. We obtain a new characterization of good modules. Also, we study good modules which have the complete max- property. The second part of this paper is devoted to investigate supplements in a coatomic module which has the complete max-property.

In this paper, we do a cryptanalyse of the so called ``Strong Diffie-Hellman-DSA Key Exchange (briefly: SDH-DSA-KE)" and after we propose ``Strong Diffie-Hellman-Exponential-Schnnor Key Exchange (briefly: SDH-XS-KE)" which is an improvement for efficiency and security. SDH-XS-KE protocol is secure against Session State Reveal (SSR) attacks, Key independency attacks, Unknown-key share (UKS) attacks and Key-Compromise Impersonation (KCI) attacks. Furthermore, SDH-XS-KE has Perfect Forward Secrecy (PFS) property and a key confirmation step. The new proposition is not vulnerable to Disclosure to ephemeral or long-term Diffie-Hellman exponents. We design our protocol in finite groups therefore this protocol can be implemented in elliptic curves.

In our paper paper we propose a new binary elliptic curve of the form $a[x^2+y^2+xy+1]+(a+b)[x^2y+y^2x]=0$. If $m\geq 5$ we prove that each ordinary elliptic curve $y^{2}+xy=x^{3}+\alpha x^2+\beta, \beta\neq 0$ over $\mathbb{F}_{2^m}$, is birationally equivalent over $\mathbb{F}_{2^m}$ to our curve. This paper also presents the formulas for the group law.

Diabetic neuropathy occurs in more than 60% of diabetic’s populations. The aim of our study wasto describe clinical and electromyography characteristics of diabetic neuropathy in a Senegalese black diabetic population (Senegal). This was a cross-sectional study of 68 neuropathic type 2 diabetic patients with 56.8years mean age. Clinical examination, Visual Analog Scale, Neuropathy Symptom Score, Disability Neuropathy Score and electro neuromyography were used to characterize neuropathy. Mean duration of diabetes was 8.7 years and mean glycosylated hemoglobin9%. Motor neuron deficit was found in one patient. The main sensory disorders were paresthesia (97%), neuropathic pain (94%), and hyperesthesia (44%). Cramps were found in 45.5% and tendon reflex abnormalities in 63.2% of cases. Tachycardia (52.9%), intestinal transit disorders (42.6%) were the most common symptom of autonomic nervous system neuropathy. High blood pressure (p=0.05) and sex (p 0.05). Diabetic neuropathy in our series is a multi variate symptom with usually mixed type. Its risks’ factors were still poorly known. Studies on larger series would better characterize it.

Children's headaches are frequently primary. Their diagnosis is difficult because of anamnesis discomfort. Aetiologies are numerous, above all functional ones as migraine. As in adults, symptomatic headache has to be taken into account among these.

A deterministic extractor for an elliptic curve, that converts a uniformly random point on the curve to a random bit-string with a uniform distribution, is an important tool in cryptography. Such extractors can be used for example in key derivation functions, in key exchange protocols and to design cryptographically secure pseudorandom number generator. In this paper, we present a simple and efficient deterministic extractor for an elliptic curve E defined over a non prime finite field. Our extractor, for a given random point P on the curve, outputs the k-first coefficients of the abscissa of the point P. This extractor confirms the two conjectures stated by Farashahi and Pellikaan (2007) and Farashahi et al. (2008), related to the extraction of bits from coordinates of a point of an elliptic curve. As applications of our extractor, we show under the decisional Diffie-Hellman problem on an elliptic curve defined over a finite field of characteristic two, that the k-first or the k-last bits of the abscissa of a random point on the curve are indistinguishable from a random bit-string of the same length.