Reinventing BEDs: Formal Treatment of Broadcast Encryption with Dealership and Practical Constructions

Broadcast Encryption allows a sender to send a message to more than one receiver. In a typical broadcast encryption, the broadcaster decides the privileged set as in who all can decrypt a particular ciphertext. Gritti et al. (IJIS\u2716) introduced a new primitive called Broadcast Encryption with Dealership (BED), where the dealer/wholesaler decides the privileged set. This rather recently introduced primitive allows a wholesaler to buy content from the broadcaster and sell it to users. Following their construction, to date, three more constructions of broadcast encryption with dealership have been proposed. Among them, the first showed the BED construction of Gritti et al. (IJIS\u2716) to be insecure. All the state-of-the-arts works were unable to fully identify the requirements of a BED scheme. We first identify and propose a new security requirement that has not been considered before. After formally defining a BED scheme, we show simple pairing-based attacks on all previous constructions rendering all of them useless. We then give the first secure BED construction in the composite-order pairing groups. This construction achieves constant-size ciphertext and secret keys but achieves selectively secure message hiding only. We then give our second construction from Li and Gong\u27s (PKC\u2718) anonymous broadcast encryption. This construction achieves adaptively secure message hiding but has ciphertext size dependent on the size of the privileged set. Following that, we propose our third and final construction that achieves constant size ciphertext in the standard model and achieves adaptive message hiding security

Reinventing BrED: A Practical Construction Formal Treatment of Broadcast Encryption with Dealership

Broadcast Encryption (BE) allows a sender to send an encrypted message to multiple receivers. In a typical broadcast encryption scenario, the broadcaster decides the set of users who can decrypt a particular ciphertext (denoted as the privileged set). Gritti et al. (IJIS\u2716) introduced a new primitive called Broadcast Encryption with Dealership (BrED), where the dealer decides the privileged set. A BrED scheme allows a dealer to buy content from the broadcaster and sell it to users. It provides better flexibility in managing a large user base. To date, quite a few different constructions of BrED schemes have been proposed by the research community. We find that all existing BrED schemes are insecure under the existing security definitions. We demonstrate a concrete attack on all the existing schemes in the purview of the existing security definition. We also find that the security definitions proposed in the state-of-the-art BrED schemes do not capture the real world. We argue about the inadequacy of existing definitions and propose a new security definition that models the real world more closely. Finally, we propose a new BrED construction and prove it to be secure in our newly proposed security model. </p

The Differential Proteome of the Probiotic Lactobacillus acidophilus NCFM Grown on the Potential Prebiotic Cellobiose Shows Upregulation of Two beta-Glycoside Hydrolases

Probiotics, prebiotics, and combinations thereof, that is, synbiotics, are known to exert beneficial health effects in humans; however interactions between pro- and prebiotics remain poorly understood at the molecular level. The present study describes changes in abundance of different proteins of the probiotic bacterium Lactobacillus acidophilus NCFM (NCFM) when grown on the potential prebiotic cellobiose as compared to glucose. Cytosolic cell extract proteomes after harvest at late exponential phase of NCFM grown on cellobiose or glucose were analyzed by two dimensional difference gel electrophoresis (2D-DIGE) in the acidic (pH 4–7) and the alkaline (pH 6–11) regions showing a total of 136 spots to change in abundance. Proteins were identified by MS or MS/MS from 81 of these spots representing 49 unique proteins and either increasing 1.5–13.9-fold or decreasing 1.5–7.8-fold in relative abundance. Many of these proteins were associated with energy metabolism, including the cellobiose related glycoside hydrolases phospho-β-glucosidase (LBA0881) and phospho-β-galactosidase II (LBA0726). The data provide insight into the utilization of the candidate prebiotic cellobiose by the probiotic bacterium NCFM. Several of the upregulated or downregulated identified proteins associated with utilization of cellobiose indicate the presence of carbon catabolite repression and regulation of enzymes involved in carbohydrate metabolism

Targeting Mitochondrial Cell Death Pathway to Overcome Drug Resistance with a Newly Developed Iron Chelate

Background: Multi drug resistance (MDR) or cross-resistance to multiple classes of chemotherapeutic agents is a major obstacle to successful application of chemotherapy and a basic problem in cancer biology. The multidrug resistance gene, MDR1, and its gene product P-glycoprotein (P-gp) are an important determinant of MDR. Therefore, there is an urgent need for development of novel compounds that are not substrates of P-glycoprotein and are effective against drug-resistant cancer. Methodology/Principal Findings: In this present study, we have synthesized a novel, redox active Fe (II) complex (chelate), iron N- (2-hydroxy acetophenone) glycinate (FeNG). The structure of the complex has been determined by spectroscopic means. To evaluate the cytotoxic effect of FeNG we used doxorubicin resistant and/or sensitive T lymphoblastic leukemia cells and show that FeNG kills both the cell types irrespective of their MDR phenotype. Moreover, FeNG induces apoptosis in doxorubicin resistance T lymphoblastic leukemia cell through mitochondrial pathway via generation reactive oxygen species (ROS). This is substantiated by the fact that the antioxidant N-acetyle-cysteine (NAC) could completely block ROS generation and, subsequently, abrogated FeNG induced apoptosis. Therefore, FeNG induces the doxorubicin resistant T lymphoblastic leukemia cells to undergo apoptosis and thus overcome MDR. Conclusion/Significance: Our study provides evidence that FeNG, a redox active metal chelate may be a promising ne

A Novel Copper Chelate Modulates Tumor Associated Macrophages to Promote Anti-Tumor Response of T Cells

At the early stages of carcinogenesis, the induction of tumor specific T cell mediated immunity seems to block the tumor growth and give protective anti-tumor immune response. However, tumor associated macrophages (TAMs) might play an immunosuppressive role and subvert this anti tumor immunity leading to tumor progression and metastasis.The Cu (II) complex, (chelate), copper N-(2-hydroxy acetophenone) glycinate (CuNG), synthesized by us, has previously been shown to have a potential usefulness in immunotherapy of multiple drug resistant cancers. The current study demonstrates that CuNG treatment of TAMs modulates their status from immunosuppressive to proimmunogenic nature. Interestingly, these activated TAMs produced high levels of IL-12 along with low levels of IL-10 that not only allowed strong Th1 response marked by generation of high levels of IFN-gamma but also reduced activation induced T cell death. Similarly, CuNG treatment of peripheral blood monocytes from chemotherapy and/or radiotherapy refractory cancer patients also modulated their cytokine status. Most intriguingly, CuNG treated TAMs could influence reprogramming of TGF-beta producing CD4(+)CD25(+) T cells toward IFN-gamma producing T cells.Our results show the potential usefulness of CuNG in immunotherapy of drug-resistant cancers through reprogramming of TAMs that in turn reprogram the T cells and reeducate the T helper function to elicit proper anti-tumorogenic Th1 response leading to effective reduction in tumor growth

Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio

Juxtaposing BTE and ATE – on the role of the European insurance industry in funding civil litigation

One of the ways in which legal services are financed, and indeed shaped, is through private insurance arrangement. Two contrasting types of legal expenses insurance contracts (LEI) seem to dominate in Europe: before the event (BTE) and after the event (ATE) legal expenses insurance. Notwithstanding institutional differences between different legal systems, BTE and ATE insurance arrangements may be instrumental if government policy is geared towards strengthening a market-oriented system of financing access to justice for individuals and business. At the same time, emphasizing the role of a private industry as a keeper of the gates to justice raises issues of accountability and transparency, not readily reconcilable with demands of competition. Moreover, multiple actors (clients, lawyers, courts, insurers) are involved, causing behavioural dynamics which are not easily predicted or influenced. Against this background, this paper looks into BTE and ATE arrangements by analysing the particularities of BTE and ATE arrangements currently available in some European jurisdictions and by painting a picture of their respective markets and legal contexts. This allows for some reflection on the performance of BTE and ATE providers as both financiers and keepers. Two issues emerge from the analysis that are worthy of some further reflection. Firstly, there is the problematic long-term sustainability of some ATE products. Secondly, the challenges faced by policymakers that would like to nudge consumers into voluntarily taking out BTE LEI

Penilaian Kinerja Keuangan Koperasi di Kabupaten Pelalawan

This paper describe development and financial performance of cooperative in District Pelalawan among 2007 - 2008. Studies on primary and secondary cooperative in 12 sub-districts. Method in this stady use performance measuring of productivity, efficiency, growth, liquidity, and solvability of cooperative. Productivity of cooperative in Pelalawan was highly but efficiency still low. Profit and income were highly, even liquidity of cooperative very high, and solvability was good