Computing Hilbert Functions using the Syzygy and LCM-lattice methods

The Hilbert function for any graded module over a field k is defined by the dimension of all of the summands M_b, where b indicates the graded component being considered. One standard approach to computing the Hilbert function is to come up with a free-resolution for the graded module M and another is via a Hilbert power series which serves as a generating function. Using combinatorics and homological algebra we develop three alternative ways to generate the values of a Hilbert function when the graded module is a quotient ring over a field. Two of these approaches (which we\u27ve called the lcm-Lattice method and the Syzygy method) are conceptually combinatorial and work for any polynomial quotient ring over a field. The third approach, which we call the Hilbert function table method, also uses syzygies but the approach is better described in terms of homological algebra

Polyhydroxybutyrate (PHB)-based triblock copolymers: synthesis of hydrophobic PHB/poly(benzyl beta-malolactonate) and amphiphilic PHB/poly(malic acid) analogues by ring-opening polymerization

International audiencePolyhydroxyalkanoates (PHAs) are biocompatible and biodegradable polyesters widely used for biomedical applications. Amphiphilic triblock copolymers with a PHB hydrophobic segment recently demonstrated attractive advantages such as high colloidal stability and low critical micellar concentration (CMC) values for the elaboration of drug delivery systems. Our approach aims at associating PHB with a fully biodegradable hydrophilic block to access new self-assembled systems with unique potential. Well-defined alpha,omega-dihydroxy telechelic PHA-based hydrophobic triblock copolymers with tunable segments length were synthesized by the controlled ring-opening polymerization (ROP) of benzyl beta-malolactonate, using polyhydroxybutyrate (PHB) diol/Nd(OTf)(3) as the catalytic system. Remarkably, the reaction proceeds with the selective oxygen-acyl bond cleavage of the beta-lactone. The corresponding amphiphilic copolymers were then obtained by hydrogenolysis. These copolymers are the only examples of fully biodegradable PHA-PHB-PHA triblock copolymers. The hydrophilic weight fraction of the copolymers was tuned from 7 to 83% upon modulating the monomer loading thus affording the ability to next access different self-assembling architectures

Symmetrically-private database search in cloud computing

Database outsourcing has gained importance in the past few years due to the emergence of the cloud computing. In Database-as-a-Service (DaaS), which is a category of cloud computing services, the database owner outsources both databases and querying services to a cloud server and clients issue queries over the database to the cloud server. In this context, privacy is a primary challenge and it is necessary to fulfill main privacy requirements of database owners and clients. This paper presents protocols for executing keyword search and aggregate SQL queries that preserve the privacy of both the client and the database owner. Client privacy is preserved such that the database owner and the cloud server cannot infer the constants contained in the query predicates. Database owner privacy is preserved such that the client cannot obtain any additional information beyond the query result. The primitives that are utilized in designing these protocols include symmetric private information retrieval and private integer comparison. We experimentally evaluate the performance of the proposed protocols and report on the experimental results. © 2013 IEEE

PRIVACY-PRESERVING QUERY PROCESSING ON OUTSOURCED DATABASES IN CLOUD COMPUTING

Database-as-a-Service (DBaaS) is a category of cloud computing services that enables IT providers to deliver database functionality as a service. In this model, a third party service provider known as a cloud server hosts a database and provides the associated software and hardware supports. Database outsourcing reduces the workload of the data owner in answering queries by delegating the tasks to powerful third-party servers with large computational and network resources. Despite the economic and technical benefits, privacy is the primary challenge posed by this category of services. By using these services, the data owners will lose the control of their databases. Moreover, the privacy of clients may be compromised since a curious cloud operator can follow the queries of a client and infer what the client is after. The challenge is to fulfill the main privacy goals of both the data owner and the clients without undermining the ability of the cloud server to return the correct query results. This thesis considers the design of protocols that protect the privacy of the clients and the data owners in the DBaaS model. Such protocols must protect the privacy of the clients so that the data owner and the cloud server cannot infer the constants contained in the query predicate as well as the query result. Moreover, the data owner privacy should be preserved by ensuring that the sensitive information in the database is not leaked to the cloud server and nothing beyond the query result is revealed to the clients. The results of the complexity and performance analysis indicates that the proposed protocols incur reasonable communication and computation overhead on the client and the data owner, considering the added advantage of being able to perform the symmetrically-private database search

Secure and private management of healthcare databases for data mining

© 2015 IEEE. There has been a tremendous growth in health data collection since the development of Electronic Medical Record (EMR) systems. Such collected data is further shared and analyzed for diverse purposes. Despite many benefits, data collection and sharing have become a big concern as it threatens individual privacy. In this paper, we propose a secure and private data management framework that addresses both the security and privacy issues in the management of medical data in outsourced databases. The proposed framework ensures the security of data by using semantically-secure encryption schemes to keep data encrypted in outsourced databases. The framework also provides a differentially-private query interface that can support a number of SQL queries and complex data mining tasks. We experimentally evaluate the performance of the proposed framework, and the results show that the proposed framework is practical and has low overhead

Linear and three-arm star hydroxytelechelic poly(benzyl β-malolactonate)s: a straightforward one-step synthesis through ring-opening polymerization

International audienceRing-opening polymn. (ROP) of racemic-benzyl β-malolactonate (MLABe) initiated by an alc. such as 1,3-propanediol (PPD) or 2-hydroxymethyl-1,3-propanediol (TMM), and catalyzed by a metal triflate M(OTf)3 with M = Nd, Bi, proceeded under mild operating conditions (in bulk at 60 °C). The functionality of the alc. dictates the topol. of the resulting hydroxy telechelic PMLABe. The ROP promoted by the neodymium-based catalytic system afforded a satisfactory activity and control in terms of molar mass and dispersity values (Mn,NMR up to 7000 g mol-1, DM \textless 1.35). Mechanistic insights revealed that ring-opening of MLABe took place through the selective oxygen-acyl bond cleavage without undesirable side reactions such as transesterification or crotonisation, as evidenced by NMR and mass spectrometry analyses of the recovered polyesters. The structure of the corresponding α,ω-hydroxy telechelic PMLABes was ascertained by 1H and 13C\1H\ NMR, SEC, and MALDI-ToF mass spectrometry analyses. In comparison, methane and trifluoromethane sulfonic acids did not allow the formation of well-defined PMLABe diols. Differences in the behavior of MLABe and the related β-butyrolactone are highlighted. The present Nd(OTf)3/PPD or TMM catalytic ROP of MLABe thus represents a valuable direct synthesis of PMLABe diols and triols, resp., without requiring chem. modification of a preformed PMLABe precursor

Investigating the Morphologic Indices of the Hamulus Pterygoid Process Using the CBCT Technique

Location and length of hamulus process plays a very important role in the efficiency of muscles such as tensor veli palatine, palato pharyngeal, upper part of upper throat muscle and so on. Given the importance of information on the morphology of the hamular process and capabilities and usefulness of CBCT in the diagnosis of its structure, this study takes place with the goal of investigating the morphologic indices (indicators) of hamulus pterygoid process using CBCT. This study investigates the CBCT images of 201 patients with the average age of 37 years, 102 males and 99 females. The length and width of the hamulus process on the left and right was measured. Also, the slope of this process in the sagittal and coronal planes were studied. Then variables in question were measured by a CBCT viewer. Average length of hamulus pterygoid process on the right was found to be 6.4 mm and on the left it was 6.5 mm. Average width of hamulus pterygoid process on the right was found to be 1.34 mm and on the left it was 1.35 mm. The average slope of the hamulus pterygoid process in the sagittal plane on the right was found to be 55.9 ° and on the left it was 56.7° The average slope of the hamulus pterygoid process in the coronal plane on the right was found to be 65.7 ° and on the left it was 66.5°. Average length and width of the hamulus process on the two sides did not make a statistically significant difference. But the average slope in the sagittal and coronal plane on the left was significantly higher than the one on the right. Average length of hamulus pterygoid process on the two sides was significantly higher in men than women. Average width of hamulus pterygoid process and the slope in the sagittal and coronal planes did not make any difference on both sides in both genders. Average length, width and slope of hamulus pterygoid process in the sagittal plan reduces on both sides with increase in age. But the slope of the hamulus pterygoid process in the coronal plane did not make any significant difference in different age groups on both sides. The slope of pterygoid process was towards the lateral in and in the sagittal plane the slope was towards the posterior. The morphological evaluation of the hamulus pterygoid process in the CBCT images can contribute to the tracking and management of vague non diagnostic symptoms in the palate

A critical Moroccan chronology: the National Institute of Fine Arts in Tetouan since 1946

This dissertation offers the first in-depth, socio-political history of the National Institute of Fine Arts in Tetouan. Organized into four chronological chapters, this study illustrates how generations of artists laid the groundwork for the development of modern and contemporary art in Morocco. My first chapter examines how the pedagogy of the Preparatory School of Fine Arts, founded in 1946 by Spanish painter Mariano Bertuchi Nieto, informed the Pictorial School of Tetouan, articulating myths of Andalusian nationalism, Hispano-Arab culture, and Hispano-Moroccan brotherhood. The role of arts and culture in Spain’s imperialist project is a lens for understanding how the colonial encounter and its afterlife affected Moroccan artists of the mid-twentieth century. My second chapter examines the post-independence period, between 1957, when the Preparatory School was re-inaugurated as the National School of Fine Arts by King Mohammed V, and the 1970s. Decades of Spanish colonialism resulted in the region’s socio-political, cultural, and economic marginalization and a disregard by scholars for seminal figures such as Ahmed Amrani, Saâd Ben Cheffaj, Meriam Maziane, Mekki Megara, and Mohamed Sarghini. I assert that rather than replicate colonial artistic styles, they were engaged in identity exploration and formal experimentations. The 1970s and 1980s in Morocco were recognized as the Years of Lead, a period of state-sponsored violence and oppression under King Hassan II, thus, in my third chapter, I delve into the work of artists responding to these tumultuous decades, such as Aziz Abou Ali, Mohamed Drissi, and Ahmed Amrani. Other artists openly reacted against the school’s marginalization and conservative pedagogy via the Spring Exhibitions, a series of five ephemeral outdoor exhibitions in al-Faddān square. Rebranded once more in 1994 as the National Institute of Fine Arts, the school has produced a generation of contemporary artists such as Mohamed Larbi Rahhali, Younès Rahmoun, and Safaa Erruas, who work primarily with Installation art and are socially and politically engaged. To that end, my fourth chapter highlights the decolonial artistic practices and pedagogical shifts introduced by innovators such as Abdelkrim Ouazzani, Mohammed Chabâa, and Faouzi Laatiris, who cultivated a more liberal artistic environment at the school.2024-03-29T00:00:00

L-tryptophane un nouveau potentiel traitement pour la cicatrisation des plaies via l'activation de la voie AhR

Des études in vitro et in vivo ont montré que des agonistes du récepteur cytoplasmique aryl hydrocarbon receptor (AhR) modulent la cicatrisation des plaies. L'acide aminé essentiel L-tryptophane pouvant être métabolisé en agonistes AhR, nous avons étudié in vitro son mécanisme d'action puis évalué sa tolérance et son efficacité comme traitement des ulcères chroniques des membres inférieurs. L'analyse in vitro montra que L-tryptophane semble moduler la cicatrisation via la oie AhR. L'étude prospective pseudo-randomisée fut réalisée sur 60 patients présentant des ulcères chroniques des membres ifnérieurs. Le traitement consista à une application d'un gel d'alginate de sodium contenant ou non 1% de L-tryptophane pendant 12 semaines. Le L-tryptophane induisit une plus forte réduction de douleur et une plus rapide réépithélialisation qui conduisit à une cicatrisation complète chez 19% des patients alors qu'aucun cas ne fut reporté dans le groupe contrôle. Ainsi, L-tryptophane apparaît comme un potentiel traitement des plaies