669 research outputs found

    Separating decision tree complexity from subcube partition complexity

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    The subcube partition model of computation is at least as powerful as decision trees but no separation between these models was known. We show that there exists a function whose deterministic subcube partition complexity is asymptotically smaller than its randomized decision tree complexity, resolving an open problem of Friedgut, Kahn, and Wigderson (2002). Our lower bound is based on the information-theoretic techniques first introduced to lower bound the randomized decision tree complexity of the recursive majority function. We also show that the public-coin partition bound, the best known lower bound method for randomized decision tree complexity subsuming other general techniques such as block sensitivity, approximate degree, randomized certificate complexity, and the classical adversary bound, also lower bounds randomized subcube partition complexity. This shows that all these lower bound techniques cannot prove optimal lower bounds for randomized decision tree complexity, which answers an open question of Jain and Klauck (2010) and Jain, Lee, and Vishnoi (2014).Comment: 16 pages, 1 figur

    Motives that Mediate the Associations Between Relationship Satisfaction, Orgasmic Difficulty, and the Frequency of Faking Orgasm

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    INTRODUCTION: Faking orgasm by women reportedly occurs quite frequently, with both relationship characteristics and orgasmic difficulty being significant predictors. AIM: We explored women's motives that might mediate the associations between orgasmic difficulty and relationship satisfaction on the one hand, with the frequency of faking orgasm on the other. METHODS: In a study of 360 Hungarian women who reported “ever” faking orgasm during partnered sex, we assessed the direct and indirect (mediated) associations between orgasmic difficulty, relationship satisfaction, and the frequency of faking orgasm. OUTCOMES: Determination of motives that mediate the association between orgasmic difficulty and the frequency of faking orgasm, and the association between relationship satisfaction and the frequency of faking orgasm. RESULTS: Increased orgasmic difficulty was directly related to increased frequency of faking orgasm (β = 0.37; P < .001), and each variable itself was related to a number of motives for faking orgasm. However, the only motive assessed in our study that mediated the relationship between orgasmic difficulty and the frequency of faking orgasm was insecurity about being perceived as abnormal or dysfunctional (indirect effect: β = 0.13; P < .001). A similar pattern emerged with relationship satisfaction and frequency of faking orgasm. These two variables were directly related in that lower relationship satisfaction predicted higher frequency of faking orgasm (β = -0.15; P = .008). Furthermore, while each variable itself was related to a number of motives for faking orgasm, the only motive assessed in our study that mediated the relationship between the 2 variables was insecurity about being perceived as abnormal or dysfunctional (indirect effect: β = -0.06; P = .008). CLINICAL TRANSLATION: Insecurity related to being perceived as abnormal or deficient, along with sexual communication, should be addressed in women with a history of faking orgasm but who want to cease doing so. STRENGTHS AND LIMITATIONS: The sample was relatively large and the online survey adhered to best practices. Nevertheless, bias may result in sample characteristics when recruitment is achieved primarily through social media. In addition, the cross-sectional sample prevented causal determination and represented Western-based values. CONCLUSIONS: The associations between orgasmic difficulty and faking orgasm, and between relationship satisfaction and faking orgasm, are both direct and indirect (mediated). The primary motive for mediating the indirect association between the predictor variables and the frequency of faking orgasm was the insecurity about being perceived as deficient or abnormal. Hevesi K, Horvath Z, Miklos E, et al. Motives that Mediate the Associations Between Relationship Satisfaction, Orgasmic Difficulty, and the Frequency of Faking Orgasm. Sex Med 2022;10:100568

    Elevated ethyl methanesulfonate (EMS) in nelfinavir mesylate (Viracept®, Roche): overview

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    Roche's protease inhibitor nelfinavir mesylate (Viracept®) produced between March 2007-June 2007 was found to contain elevated levels of ethyl methanesulfonate (EMS), a known mutagen (alkylator) – leading to a global recall of the drug. EMS levels in a daily dose (2,500 mg Viracept/day) were predicted not to exceed a dose of ~2.75 mg/day (~0.055 mg/kg/day based on 50 kg patient). As existing toxicology data on EMS did not permit an adequate patient risk assessment, a comprehensive animal toxicology evaluation of EMS was conducted. General toxicity of EMS was investigated in rats over 28 days. Two studies for DNA damage were performed in mice; chromosomal damage was assessed using a micronucleus assay and gene mutations were detected using the MutaMouse transgenic model. In addition, experiments designed to extrapolate animal exposure to humans were undertaken. A general toxicity study showed that the toxicity of EMS occurred only at doses ≥ 60 mg/kg/day, which is far above that received by patients. Studies for chromosomal damage and mutations in mice demonstrated a clear threshold effect with EMS at 25 mg/kg/day, under chronic dosing conditions. Exposure analysis (Cmax) demonstrated that ~370-fold higher levels of EMS than that ingested by patients, are needed to saturate known, highly conserved, error-free, mammalian DNA repair mechanisms for alkylation. In summary, animal studies suggested that patients who took nelfinavir mesylate with elevated levels of EMS are at no increased risk for carcinogenicity or teratogenicity over their background risk, since mutations are prerequisites for such downstream events. These findings are potentially relevant to >40 marketed drugs that are mesylate salts

    The White-Box Adversarial Data Stream Model

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    We study streaming algorithms in the white-box adversarial model, where the stream is chosen adaptively by an adversary who observes the entire internal state of the algorithm at each time step. We show that nontrivial algorithms are still possible. We first give a randomized algorithm for the L1L_1-heavy hitters problem that outperforms the optimal deterministic Misra-Gries algorithm on long streams. If the white-box adversary is computationally bounded, we use cryptographic techniques to reduce the memory of our L1L_1-heavy hitters algorithm even further and to design a number of additional algorithms for graph, string, and linear algebra problems. The existence of such algorithms is surprising, as the streaming algorithm does not even have a secret key in this model, i.e., its state is entirely known to the adversary. One algorithm we design is for estimating the number of distinct elements in a stream with insertions and deletions achieving a multiplicative approximation and sublinear space; such an algorithm is impossible for deterministic algorithms. We also give a general technique that translates any two-player deterministic communication lower bound to a lower bound for {\it randomized} algorithms robust to a white-box adversary. In particular, our results show that for all p0p\ge 0, there exists a constant Cp>1C_p>1 such that any CpC_p-approximation algorithm for FpF_p moment estimation in insertion-only streams with a white-box adversary requires Ω(n)\Omega(n) space for a universe of size nn. Similarly, there is a constant C>1C>1 such that any CC-approximation algorithm in an insertion-only stream for matrix rank requires Ω(n)\Omega(n) space with a white-box adversary. Our algorithmic results based on cryptography thus show a separation between computationally bounded and unbounded adversaries. (Abstract shortened to meet arXiv limits.)Comment: PODS 202

    Robust Design Optimization of Electrical Machines and Devices

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    The article introduces a Special Issue (SI) of the journal Electronica that contains fourteen chosen articles from robust design optimization of electrical machines and devices. Optimization is essential for the research and design of electro-mechanical devices, especially electrical machines. Finding the optimal solutions may lead to cheaper, more economical products, faster and more efficient production, or more sustainable solutions. However, optimizing such a complex system as an electrical machine is a computationally expensive optimization problem, where many physical domains should be considered together. Practical design needs to consider the electrical device’s design parameters; it should be insensitive to parameter changes or manufacturing tolerances. This Special Issue focused on papers showing how modern artificial intelligence (AI) tools can be used for robust design optimization of electric machines and electrical devices, how these tools can be tested, or the correctness of the result validated

    Immune Recognition of the 60kD Heat Shock Protein: Implications for Subsequent Fertility

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    The 60kD heat shock protein (hsp60) is a highly conserved protein and a dominant antigen of most pathogenic bacteria. In some women, chronic or repeated upper genital tract infections with Chlamydia trachomatis, and possibly with other microorganisms, induces immune sensitization to epitopes of hsp60 that are present in both the microbial and human hsp60. Once a woman becomes sensitized to these conserved epitpes, any subsequent induction of human or bacterial hsp60 expression will reactivate hsp60-sensitized lymphocytes and initiate a pro-inflammatory immune response. Hsp60 is expressed during the early stages of pregnancy, by both the embryo and the maternal decidua. We examined, therefore, whether women who were sensitized to hsp60 experienced less successful pregnancy outcomes compared to women who were not sensitized to this antigen. In women undergoing in vitro fertilization (IVF), the presence of cervical IgA antibodies reactive with the C. trachomatis hsp60 correlated with implantation failure after embryo transfer. Further analysis revealed that an immunodominant epitope for these IgA antibodies was an hsp60 epitope shared between C. trachomatis and man. In subsequent studies of women not undergoing IVF, cervical IgA antibodies to the human hsp60 were identified in 13 of 91 reproductive age women. This antibody was most prevalent in those women with a history of primary infertility (p = 0.003). In addition, cervical anti-hsp60 IgA correlated with the detection of the pro-inflammatory cytokines interferon-γ (p = 0.001) and tumor necrosis factor-α (p = 0.02) in the cervix. Conversely, women with proven fertility had the highest prevalence of the anti-inflammatory cytokine, interleukin 10, in their cervices (p = 0.001). In an analysis of serum samples in a third study, women with a history of two or more consecutive first trimester spontaneous abortions had a higher prevalence (p = 0.01) of IgG antibodies to the human hsp60 (36.8%) than did age matched fertile women (11.1%) or women with primary infertility (11.8%). Immune sensitization to epitopes expressed by the human hsp60 may reduce the probability of a successful pregnancy outcome due to reactivation of hsp60-reactive lymphocytes, induction of a pro-inflammatory cytokine response and interference with early embryo development and/or implantation

    Transverse Expansion and High pTp_T Azimuthal Asymmetry at RHIC

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    Rapid 3+1D transverse plus Bjorken collective expansion in A+AA+A collisions at ultra-relativistic energies is shown to reduce substantially the azimuthal asymmetry resulting from jet quenching. While the azimuthal asymmetry in non-central collisions, v2(pT>2GeV/c)0.15v_2(p_T>2 \rm{GeV/c})\sim 0.15 reported by STAR at RHIC, can be accounted for by spatially anisotropic jet energy loss through a 1+1D expanding gluon plasma with dNg/dy1000dN^g/dy\sim 1000, we show that if rapid transverse collective expansion of the plasma is assumed, then the asymmetry due to jet quenching may be reduced below the observed level. Possible implications of this effect are discussed.Comment: Journal version: 1 figure added, references added. 6 pages, 4 figure
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