239 research outputs found

    On Packet Scheduling with Adversarial Jamming and Speedup

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    In Packet Scheduling with Adversarial Jamming packets of arbitrary sizes arrive over time to be transmitted over a channel in which instantaneous jamming errors occur at times chosen by the adversary and not known to the algorithm. The transmission taking place at the time of jamming is corrupt, and the algorithm learns this fact immediately. An online algorithm maximizes the total size of packets it successfully transmits and the goal is to develop an algorithm with the lowest possible asymptotic competitive ratio, where the additive constant may depend on packet sizes. Our main contribution is a universal algorithm that works for any speedup and packet sizes and, unlike previous algorithms for the problem, it does not need to know these properties in advance. We show that this algorithm guarantees 1-competitiveness with speedup 4, making it the first known algorithm to maintain 1-competitiveness with a moderate speedup in the general setting of arbitrary packet sizes. We also prove a lower bound of ϕ+12.618\phi+1\approx 2.618 on the speedup of any 1-competitive deterministic algorithm, showing that our algorithm is close to the optimum. Additionally, we formulate a general framework for analyzing our algorithm locally and use it to show upper bounds on its competitive ratio for speedups in [1,4)[1,4) and for several special cases, recovering some previously known results, each of which had a dedicated proof. In particular, our algorithm is 3-competitive without speedup, matching both the (worst-case) performance of the algorithm by Jurdzinski et al. and the lower bound by Anta et al.Comment: Appeared in Proc. of the 15th Workshop on Approximation and Online Algorithms (WAOA 2017

    Probabilistic Bounds on the Length of a Longest Edge in Delaunay Graphs of Random Points in d-Dimensions

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    Motivated by low energy consumption in geographic routing in wireless networks, there has been recent interest in determining bounds on the length of edges in the Delaunay graph of randomly distributed points. Asymptotic results are known for random networks in planar domains. In this paper, we obtain upper and lower bounds that hold with parametric probability in any dimension, for points distributed uniformly at random in domains with and without boundary. The results obtained are asymptotically tight for all relevant values of such probability and constant number of dimensions, and show that the overhead produced by boundary nodes in the plane holds also for higher dimensions. To our knowledge, this is the first comprehensive study on the lengths of long edges in Delaunay graphsComment: 10 pages. 2 figures. In Proceedings of the 23rd Canadian Conference on Computational Geometry (CCCG 2011). Replacement of version 1106.4927, reference [5] adde

    PERLINDUNGAN HUKUM TERHADAP RESEP MINUMAN KOPI NUJU DALAM PRESPEKTIF RAHASIA DAGANG (Studi Pada Kemenkumham dan Nuju Bandar Lampung)

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    ABSTRAK Coffee shop merupakan suatu bisnis yang sedang berkembang pesat di era industri saat ini. Permasalahan yang terdapat pada bisnis coffee shop dalam hal ini adalah terjadinya persaingan yang curang dalam bentuk pelanggaran rahasia dagang yang berupa pembocoran atau pencurian terhadap resep dan bahan biji kopi yang digunakan. Dari penelitian ini diperoleh hasil bahwa informasi rahasia dagang dalam bisnis Coffee Shop yang berupa resep dan bahan biji kopi telah dilindungi oleh hukum dan tidak boleh diketahui oleh umum. Pihak yang telah menyalahgunakan atau membocorkan informasi rahasia dagang dapat dikenai sanksi perdata dan sanksi pidana yang telah diatur dalam UU No. 30 tahun 2000. Melihat masih banyak para pekerja yang membocorkan informasi rahasia dagang maka perlu adanya perjanjian kerja secara tertulis mengenai larangan untuk menyalahgunakan atau membocorkan rahasia dagang agar bisa digunakan sebagai alat untuk menuntut jika terjadi pelanggaran rahasia dagang. Pendekatan yang digunakan dalam penelitian ini adalah pendekatan yuridis normatif dan pendekatan yuridis empiris untuk mendapatkan hasil penelitian yang benar dan objektif. Kemudian untuk proses analisis data, data yang telah disusun secara sistematis dianalisis secara yuridis kualitatif yaitu dengan memberikan pemahaman terhadap data sesuai dengan fakta yang diperoleh di lapangan, sehingga benar-benar dari pokok bahasannya. di tangan dan disusun dalam kalimat demi kalimat. yang ilmiah dan sistematis berupa jawaban atas permasalahan berdasarkan hasil penelitian. Tujuan penelitian ini untuk mengetahui bentuk perlindungan hukum bagi rahasia dagang pada resep minuman kopi nuju dalam prespektif rahasia dagang dan cara penyelesaian sengketa rahasia dagang apabila terjadi pelanggaran pada kedai kopi nuju

    Biocosmetics made with Saccharina latissima fractions from sustainable treatment: physicochemical and thermorheological features

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    This work deals with the formulation of natural cosmetics enriched with antioxidant fractions from the ultrasound treatment (US) of the brown seaweed Saccharina latissima. The challenge was the development of a cosmetic matrix without jeopardizing the thermorheological features of the creams, adding microparticles containing the antioxidant fractions using two different carriers, mannitol and alginate. The fundamental chemical characteristics of seaweed and the extracts obtained via sonication, as well as the antioxidant properties of the latter, were analyzed. The highest TEAC (Trolox equivalent antioxidant capacity) value was identified for the extracts subjected to the longest processing time using ultrasound-assisted extraction (240 min). A similar yield of microparticle formulation (around 60%) and load capacity (about 85%) were identified with mannitol and alginate as carriers. Color testing of the creams exhibited small total color differences. The rheological results indicated that the testing temperature, from 5 to 45 °C, notably influenced the apparent viscosity of the matrices. All creams were adequately fitted with the two parameters of the Ostwald–de Waele model, with the flow consistency index following an Arrhenius dependency with the testing temperature. Neither hysteresis nor water syneresis was observed in the proposed cosmetics during 6 months of cold storage at 4–6 °C.Portomuiños company | Ref. IN-0214-21Portomuiños company | Ref. IN-0077-21Xunta de Galicia | Ref. ED431F 2020/01Xunta de Galicia | Ref. ED481D-2022-018Agencia Estatal de Investigación | Ref. RYC2018-024454-IXunta de Galicia | Ref. ED431C 2022/0

    The Role of Surface Recombination on the Performance of Perovskite Solar Cells:Effect of Morphology and Crystalline Phase of TiO<sub>2</sub> Contact

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    Herein, the preparation of 1D TiO2 nanocolumnar films grown by plasma-enhanced chemical vapor deposition is reported as the electron selective layer (ESL) for perovskite solar devices. The impact of the ESL architecture (1D and 3D morphologies) and the nanocrystalline phase (anatase and amorphous) is analyzed. For anatase structures, similar power conversion efficiencies are achieved using an ESL either the 1D nanocolumns or the classical 3D nanoparticle film. However, lower power conversion efficiencies and different optoelectronic properties are found for perovskite devices based on amorphous 1D films. The use of amorphous TiO2 as electron selective contact produces a bump in the reverse scan of the current–voltage curve as well as an additional electronic signal, detected by impedance spectroscopy measurements. The dependence of this additional signal on the optical excitation wavelength used in the IS experiments suggests that it stems from an interfacial process. Calculations using a drift-diffusion model which explicitly considers the selective contacts reproduces qualitatively the main features observed experimentally. These results demonstrate that for a solar cell in which the contact is working properly the open-circuit photovoltage is mainly determined by bulk recombination, whereas the introduction of a “bad contact” shifts the balance to surface recombination.</p

    k-FGF protoncogene expression is associated with murine testicular teratogenesis, but is not involved during mouse testicular development

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    A l'article en PDF consta com a vol.11 (1996)The k-FGF gene, which belongs to the family of the fibroblast growth factor genes, is implicated in tumoral and developmental processes. It is expressed in embryonal carcinoma cells, in embryonic stem cells, during limb and tooth formation and in some germ cell tumors. However, the expression of this protooncogene during testicular development as well its relationship to spontaneous teratogenesis have not been determined. Here we investigate k-FGF xpression during testicular development in mice, as well as in a spontaneous testicular teratoma (STT) and in the OTT6050 teratocarcinoma (TC) by Northern blotting, RT-PCR and in situ hybridization. Severa1 data indicate that k-FGF gene contains downstream regulatory sequences which bind octamer factors. One of these transcription factors which binds to k-FGF enhancer is Oct-4. Although the k-FGF gene is activated by Oct-4 in embryonal carcinoma and embryonic stem cells and Oct-4 is expressed in the germ cells of the embryo, our results indicate that there is no detectable k-FGF expression in mouse testicular germ cells at any stage of development. This indicates that Oct-4 does not activate transcription of the k-FGF gene in mouse germ cells, and that k-FGF is not implicated during testicular development. We also show that there is a high k-FGF expression in the experimental OTT6050 TC, but only very low levels in a murine differentiated STT, suggesting that k-FGF activation may be responsible for the genesis and development of STT, behaving as a marker of malignancy in these neoplasms

    An orbital-free molecular dynamics study of melting in K_20, K_55, K_92, K_142, Rb_55 and Cs_55 clusters

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    The melting-like transition in potasium clusters K_N, with N=20, 55, 92 and 142, is studied by using an orbital-free density-functional constant-energy molecular dynamics simulation method, and compared to previous theoretical results on the melting-like transition in sodium clusters of the same sizes. Melting in potasium and sodium clusters proceeds in a similar way: a surface melting stage develops upon heating before the homogeneous melting temperature is reached. Premelting effects are nevertheless more important and more easily established in potasium clusters, and the transition regions spread over temperature intervals which are wider than in the case of sodium. For all the sizes considered, the percentage melting temperature reduction when passing from Na to K clusters is substantially larger than in the bulk. Once those two materials have been compared for a number of different cluster sizes, we study the melting-like transition in Rb_55 and Cs_55 clusters and make a comparison with the melting behavior of Na_55 and K_55. As the atomic number increases, the height of the specific heat peaks decreases, their width increases, and the melting temperature decreases as in bulk melting, but in a more pronounced way.Comment: LaTeX file. 6 pages with 17 pictures. Final version with minor change

    Sur8, a determinant protein in colorectal cancer tumor progression

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    Resumen del trabajo presentado en el 43rd Annual Meeting of the SEBBM, celebrado en Barcelona (España) del 19 al 21 de julio de 2021.Colorectal cancer (CRC) has the highest incidence rate in the Spanish population. The most important challenge consists on the discovery of efficient disease treatments, due to high mortality rates in highly developed stages. Sur8 is a scaffold protein that positively modulates ERK signaling pathway, which has a major role in the progression and metastasis in colorectal cancer. The main goals of our research are to determine the role that Sur8 plays in the development and progression of CRC and to analyze its possible therapeutic potential. For this purpose, our group has developed an inducible conditional mouse model msur8f/fVillinCreERT2. In order to determine Sur8 action in the colonic tissue, we have developed organoids from the colon epithelium of healthy mice and have analyzed gene expression pattern by an RNAseq approach. Sur8 KO affects oncogenic CRC transcription factors expression, as well as the modulation of some Wnt pathway regulators. In regard to miRNA data, we have observed deregulation of miRNAs related to CRC in Sur8 KO organoids. To determine the role that Sur8 plays in the development and progression of CRC, we have subjected our inducible conditional mice to chemical carcinogenesis and we have observed that Sur8 KO males display less and smaller tumors and do not present any adenocarcinoma. In addition, we have carried out Sur8 silencing in human CRC cell lines by infection with constitutive shRNA lentiviruses. We have observed that Sur8 silencing produces decreases of cell tumor proliferation, and reduction of p-ERK levels. Finally, we are evaluating the effects of putative therapeutic agents against Sur8 in human CRC cell lines. Concretely, we are testing Celastrol, which has been described that binds and blocks the action of Sur8 in vitro. We have observed that Celastrol treatment diminishes the cell tumor proliferation in this model. Altogether, our results indicate that Sur8 may have a determinant role in CRC progression and that Sur8 could be a potential molecular target for the design of novel strategies against CRC

    Intravascular Large B-Cell Lymphoma Genomic Profile Is Characterized by Alterations in Genes Regulating NF-κB and Immune Checkpoints.

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    Intravascular large B-cell lymphoma (IVLBCL) is an uncommon lymphoma with an aggressive clinical course characterized by selective growth of tumor cells within the vessels. Its pathogenesis is still uncertain and there is little information on the underlying genomic alterations. In this study, we performed a clinicopathologic and next-generation sequencing analysis of 15 cases of IVLBCL using a custom panel for the detection of alterations in 68 recurrently mutated genes in B-cell lymphomagenesis. Six patients had evidence of hemophagocytic syndrome. Four patients presented concomitantly a solid malignancy. Tumor cells outside the vessels were observed in 7 cases, 2 with an overt diffuse large B-cell cell lymphoma. In 4 samples, tumor cells infiltrated lymphatic vessel in addition to blood capillaries. Programmed death-ligand 1 (PD-L1) was positive in tumor cells in 4 of 11 evaluable samples and in macrophages intermingled with tumor cells in 8. PD-L1 copy number gains were identified in a higher proportion of cases expressing PD-L1 than in negative tumors. The most frequently mutated gene was PIM1 (9/15, 60%), followed by MYD88L265P and CD79B (8/15, 53% each). In 6 cases, MYD88L265P and CD79B mutations were detected concomitantly. We also identified recurrent mutations in IRF4 , TMEM30A , BTG2 , and ETV6 loci (4/15, 27% each) and novel driver mutations in NOTCH2 , CCND3 , and GNA13 , and an IRF4 translocation in 1 case each. The mutational profile was similar in patients with and without evidence of hemophagocytic syndrome and in cases with or without dissemination of tumor cells outside the vessels. Our results confirm the relevance of mutations in B-cell receptor/nuclear factor-κB signaling and immune escape pathways in IVLBCL and identify novel driver alterations. The similar mutational profile in tumors with extravascular dissemination suggests that these cases may also be considered in the spectrum of IVLBCL
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