Isolation, synthesis and optimization of cyclopropanation process of 4-allyl-2-methoxyphenol

The synthesis of 4-((2,2-dichlorocyclopropyl)methyl)-2-methoxyphenol 2 have been accomplished by using cyclopropanation process and Reponse Surface Methodology [1,2]. This methodology was used to determine the optimal conditions for the cyclopropanation reaction of eugenol 1. The reaction time (X1) and the ratio of the reaction mixture’s solvent (X2) were the two investigated factors. The statistical analysis of this study indicates that both of these factors had significant effects on the cyclopropanation yield. The central composite design showed that polynomial regression models were in good agreement with the experimental results of the coefficient determination (0.95) of product 2 yield. The optimal conditions were 17.44 and 5.78 hours. In such condition, the predicted yield of the product 2 was 43.96%. Keywords: Eugenol; 4-((2,2-dichlorocyclopropyl)methyl)-2-methoxyphenol; Central composite design; Optimization experiment

Heteroatom substitution effects in spin crossover dinuclear complexes

We probe the effect of heteroatom substitution on the spin crossover (SCO) properties of dinuclear materials of the type [Fe2(NCX)4(R-trz)5]·S (X = S, Se; S = solvent; R-trz = (E)-N-(furan-2-ylmethylene)- 4H-1,2,4-triazol-4-amine (furtrz); (E)-N-(thiophen-2-ylmethylene)-4H-1,2,4-triazole-4-amine (thtrz)). For the furtrz family ([Fe2(NCX)4(furtrz)5]·furtrz·MeOH; X = S (furtrz-S) and X = Se (furtrz-Se)) gradual and incomplete one-step SCO transitions are observed (furtrz-S (T1/2 = 172 K) and furtrz-Se (T1/2 = 205 K)) and a structural evolution from [HS-HS] to [HS-LS] per dinuclear species. Contrasting this, within the thtrz family ([Fe2(NCX)4(thtrz)5]·4MeOH; X = S (thtrz-S) and X = Se (thtrz-Se)) more varied SCO transitions are observed, with thtrz-S being SCO-inactive (high spin) and thtrz-Se showing a rare complete two-step SCO transition (T1/2(1,2) = 170, 200 K) in which the FeII sites transition from [HS-HS] to [HS-LS] to [LS-LS] per dinuclear unit with no long range ordering of spin-states at the intermediate plateau. Detailed structure- function analyses have been conducted within this growing dinuclear family to rationalise these diverse spin-switching properties

The Robust Stream Cipher for Securing Data in the Smartphones

مع التطور الحاصل في أجهزة الاتصالات وتكنولوجيا المعلومات وانتشارها بمساحات واسعة في العالم  ادى ذلك الى زيادة المشاكل الامنية اثناء انتقال البيانات عبر تلك الاجهزة، على سبيل المثال تسرب البيانات، تعديلها، الوصول الغير مصرح به، و تعرضها الى الهجمات. توجد عدة انواع من التقنيات التي تستخدم لمنع حدوث هذه المشاكل وتعمل على حماية البيانات. أحدى هذه التقنيات هي التشفير الانسيابي التي تعتبر من اقوى واسرع الطرق المستخدمة في عملية التشفير وفك التشفير. في هذا البحث قدمنا تصميم جديد للتشفير الانسيابي لحماية بيانات الهاتف. قوة التشفير الانسيابي تعتمد على المفتاح. توجد عدة طرق تستخدم لغرض توليد المفتاح. استخدمنا ثلاثة انواع من المولدات(LFSR,FCSR,NLFSR) وبعد ذلك استخدمنا Non-linear Boolean function من نوع (f combination function) من نوع خمسة متغيرات، لجعل المولد اكثر اماناً. قمنا بدمج هذه الانواع الثلاثة وذلك بادخال أربعة مولدات من نوع LFSR  مع احدى مولدات FCSR  أو NLFSR الى f. بعد ذلك قمنا باختبار المفتاح من خلال قياس عشوائيته (التي تعتبر من اهم المعايير الاساسية لقياس كفاءة المولد) باستخدام اختبارات NIST statistical tests.With the development of network and communication systems in large areas in the world, this leads to increase security problems in transmission of data such as data leakage, modification, unauthorized access, and attacks. There are many types of techniques that are used to prevent these problems and protect data. One of these techniques is a stream cipher which considered the strongest and fastest method used in encryption and decryption process. In this study presented a new design for the stream cipher to protect mobile data. The strength of stream cipher depends on it is' key. There are several methods to generate key. We used three types of generator. Then, it used the combiner to convert them into a nonlinear Boolean function in order to make the generator key more secure. To implement a new generator key by using these three kinds, we used four LFSRs and one of NLFSRs or FCSRs to produce five variables Boolean function. These variables will be as an input to the combiner function. Finally, we tested the generator and submitted it to the randomness tests that is publicly available in the National Institute of Standards and Technology (NIST)

Valorisation des produits laitiers typiques de Bizerte et Béja : diagnostic et stratégie locale

Publication du projet européen LACTIMED (ANIMA / CIHEAM-IAMM) avec le Pôle de Compétitivité de Bizerte (PCB)Lactimed a réalisé un diagnostic de la filière laitière de Bizerte et Béja (Tunisie) afin d’aider les autorités locales et les structures d’appui à adopter une stratégie pour la valorisation des produits laitiers typiques de leur territoire. Ce rapport de diagnostic inclut un état des lieux de la filière, l’analyse des résultats d’enquêtes de terrain menées auprès des producteurs, l’identification de produits laitiers typiques avec leur cahier des charges de production et des informations sur le marché domestique

Valorisation des produits laitiers typiques de Bizerte et Béja : diagnostic et stratégie locale

Publication du projet européen LACTIMED (ANIMA / CIHEAM-IAMM) avec le Pôle de Compétitivité de Bizerte (PCB)Lactimed a réalisé un diagnostic de la filière laitière de Bizerte et Béja (Tunisie) afin d’aider les autorités locales et les structures d’appui à adopter une stratégie pour la valorisation des produits laitiers typiques de leur territoire. Ce rapport de diagnostic inclut un état des lieux de la filière, l’analyse des résultats d’enquêtes de terrain menées auprès des producteurs, l’identification de produits laitiers typiques avec leur cahier des charges de production et des informations sur le marché domestique

Synthesis and characterisation of novel nanospheres made from amphiphilic perfluoroalkylthio-β-cyclodextrins

International audienc

Heteroatom substitution effects in spin crossover dinuclear complexes

We probe the effect of heteroatom substitution on the spin crossover (SCO) properties of dinuclear materials of the type [Fe2(NCX)4(R-trz)5]·S (X = S, Se; S = solvent; R-trz = (E)-N-(furan-2-ylmethylene)-4H-1,2,4-triazol-4-amine (furtrz); (E)-N-(thiophen-2-ylmethylene)-4H-1,2,4-triazole-4-amine (thtrz)). For the furtrz family ([Fe2(NCX)4(furtrz)5]·furtrz·MeOH; X = S (furtrz-S) and X = Se (furtrz-Se)) gradual and incomplete one-step SCO transitions are observed (furtrz-S (T1/2 = 172 K) and furtrz-Se (T1/2 = 205 K)) and a structural evolution from [HS–HS] to [HS–LS] per dinuclear species. Contrasting this, within the thtrz family ([Fe2(NCX)4(thtrz)5]·4MeOH; X = S (thtrz-S) and X = Se (thtrz-Se)) more varied SCO transitions are observed, with thtrz-S being SCO-inactive (high spin) and thtrz-Se showing a rare complete two-step SCO transition (T1/2(1,2) = 170, 200 K) in which the FeII sites transition from [HS–HS] to [HS–LS] to [LS–LS] per dinuclear unit with no long range ordering of spin-states at the intermediate plateau. Detailed structure–function analyses have been conducted within this growing dinuclear family to rationalise these diverse spin-switching properties

Synthesis and Structure-Activity Relationships of Inhibitors That Target the C-Terminal MEEVD on Heat Shock Protein 90

Herein, we describe the synthesis and structure-activity relationships of cyclic peptides designed to target heat shock protein 90 (Hsp90). Generating 19 compounds and evaluating their binding affinity reveals that increasing electrostatic interactions allows the compounds to bind more effectively with Hsp90 compared to the lead structure. Exchanging specific residues for lysine improves binding affinity for Hsp90, indicating some residues are not critical for interacting with the target, whereas others are essential. Replacing l- for d-amino acids produced compounds with decreased binding affinity compared to the parent structure, confirming the importance of conformation and identifying key residues most important for binding. Thus, a specific conformation and electrostatic interactions are required in order for these inhibitors to bind to Hsp90