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In this paper, we start with a discussion of discrete Gaussian measures on lattices. Several results of Banaszczyk are analyzed, a simple form of uncertainty principle for discrete Gaussian measure is formulated. In the second part of the paper we prove two new bounds for the smoothing parameter of lattices. Under the natural assumption that $$\varepsilon$$ is suitably small, we obtain two estimations of the smoothing parameter

Let \(E_a/ \mathbb {F}_{2}: y^2+xy=x^3+ax^2+1\) be a Koblitz curve. The window \(\tau \)-adic non-adjacent form (window \(\tau \)NAF) is currently the standard representation system to perform scalar multiplications on \(E_a/ \mathbb {F}_{2^m}\) utilizing the Frobenius map \(\tau \). This work focuses on the pre-computation part of scalar multiplication. We first introduce \(\mu \bar{\tau }\)-operations where \(\mu =(-1)^{1-a}\) and \(\bar{\tau }\) is the complex conjugate of \(\tau \). Efficient formulas of \(\mu \bar{\tau }\)-operations are then derived and used in a novel pre-computation scheme. Our pre-computation scheme requires 6M\(\,+\,6\)S, 18M\(\,+\,17\)S, 44M\(\,+\,32\)S, and 88M\(\,+\,62\)S (\(a=0\)) and 6M\(\,+\,6\)S, 19M\(\,+\,17\)S, 46M\(\,+\,32\)S, and 90M\(\,+\,62\)S (\(a=1\)) for window \(\tau \)NAF with widths from 4 to 7 respectively. It is about two times faster, compared to the state-of-the-art technique of pre-computation in the literature. The impact of our new efficient pre-computation is also reflected by the significant improvement of scalar multiplication. Traditionally, window \(\tau \)NAF with width at most 6 is used to achieve the best scalar multiplication. Because of the dramatic cost reduction of the proposed pre-computation, we are able to increase the width for window \(\tau \)NAF to 7 for a better scalar multiplication. This indicates that the pre-computation part becomes more important in performing scalar multiplication. With our efficient pre-computation and the new window width, our scalar multiplication runs in at least 85.2% the time of Kohel’s work (Eurocrypt’2017) combining the best previous pre-computation. Our results push the scalar multiplication of Koblitz curves, a very well-studied and long-standing research area, to a significant new stage.

Despite widespread use of the bacille Calmette-Guerin (BCG) vaccine, tuberculosis (TB) remains a leading cause of global mortality from a single infectious agent (Mycobacterium tuberculosis or Mtb). Here, over two independent Mtb challenge studies, we demonstrate that subcutaneous vaccination of rhesus macaques (RMs) with rhesus cytomegalovirus vectors encoding Mtb antigen inserts (hereafter referred to as RhCMV/TB)-which elicit and maintain highly effector-differentiated, circulating and tissue-resident Mtb-specific CD4+ and CD8+ memory T cell responses-can reduce the overall (pulmonary and extrapulmonary) extent of Mtb infection and disease by 68%, as compared to that in unvaccinated controls, after intrabronchial challenge with the Erdman strain of Mtb at ∼1 year after the first vaccination. Fourteen of 34 RhCMV/TB-vaccinated RMs (41%) across both studies showed no TB disease by computed tomography scans or at necropsy after challenge (as compared to 0 of 17 unvaccinated controls), and ten of these RMs were Mtb-culture-negative for all tissues, an exceptional long-term vaccine effect in the RM challenge model with the Erdman strain of Mtb. These results suggest that complete vaccine-mediated immune control of highly pathogenic Mtb is possible if immune effector responses can intercept Mtb infection at its earliest stages.

The development of a sterilizing vaccine against malaria remains one of the highest priorities for global health research. While sporozoite vaccines targeting the pre-erythrocytic stage show great promise, it has not been possible to maintain efficacy long-term, likely due to an inability of these vaccines to maintain effector memory T cell responses in the liver. Vaccines based on human cytomegalovirus (HCMV) might overcome this limitation since vectors based on rhesus CMV (RhCMV), the homologous virus in rhesus macaques (RM), elicit and indefinitely maintain high frequency, non-exhausted effector memory T cells in extralymphoid tissues, including the liver. Moreover, RhCMV strain 68–1 elicits CD8+ T cells broadly recognizing unconventional epitopes exclusively restricted by MHC-II and MHC-E. To evaluate the potential of these unique immune responses to protect against malaria, we expressed four Plasmodium knowlesi (Pk) antigens (CSP, AMA1, SSP2/TRAP, MSP1c) in RhCMV 68–1 or in Rh189-deleted 68–1, which additionally elicits canonical MHC-Ia-restricted CD8+ T cells. Upon inoculation of RM with either of these Pk Ag expressing RhCMV vaccines, we obtained T cell responses to each of the four Pk antigens. Upon challenge with Pk sporozoites we observed a delayed appearance of blood stage parasites in vaccinated RM consistent with a 75–80% reduction of parasite release from the liver. Moreover, the Rh189-deleted RhCMV/Pk vectors elicited sterile protection in one RM. Once in the blood, parasite growth was not affected. In contrast to T cell responses induced by Pk infection, RhCMV vectors maintained sustained T cell responses to all four malaria antigens in the liver post-challenge. The delayed appearance of blood stage parasites is thus likely due to a T cell-mediated inhibition of liver stage parasite development. As such, this vaccine approach can be used to efficiently test new T cell antigens, improve current vaccines targeting the liver stage and complement vaccines targeting erythrocytic antigens.

Koblitz curves have been an important subject of consideration for both theoretical andpractical interests. The window $\tau$ -adic algorithm of Solinas (window $\tau$ NAF) is the most powerful method for computing point multiplication for Koblitz curves.Pre-computation plays an important role in improving the performance of point multiplication. In this paper, the concept of optimal pre-computation for window $\tau$ NAF is formulated. In this setting, an optimal pre-computation has some mathematically natural and clean forms, and requires $2^{w-2}-1$ point additions and two evaluations of the Frobenius map $\tau$ , where $w$ is the window width. One of the main results of this paper is to construct an optimal pre-computation scheme for each window width $w$ from $4$ to $15$ (more than practical needs).These pre-computations can be easily incorporated into implementations of window $\tau$ NAF. The ideas in the paper can also be used to construct other suitable pre-computations. This paper includes a discussion of coefficient sets for window $\tau$ NAF and the divisibility by powers of $\tau$ through different approaches. Some issues of implementation are also discussed.

This paper proposes a scheme for password management by storing password encryptions on a server. The method involves having the encryption key split into a share for the user and one for the server. The user’s share shall be based solely on a selected passphrase. The server’s share shall be generated from the user’s share and the encryption key. The security and trust are achieved by performing both encryption and decryption on the client side. We also address the issue of countering dictionary attack by providing a further enhancement of the scheme.

The orthogonalized integer representation wasindependently proposed by Ding et al. using genetic algorithm and Fukase et al. using sampling technique to solve shortest vector problem (SVP).Their results are promising.In this paper, we consider sparse orthogonalized integer representations for shortest vectors and propose a new enumeration method,called orthognalized enumeration, by integratingsuch a representation. Furthermore, we present a mixed BKZ method, called MBKZ, by alternately applying orthognalized enumeration andother existing enumeration methods. Compared to the existing ones,our methods have greater efficiency and achieve exponential speedups both in theory and in practice for solving SVP.Implementations of our algorithms have been tested to be effective in solving challenging lattice problems.

In estimating frequencies given that the signal waveforms are undersampled multiple times, Xia et al. proposed to use a generalized version of Chinese remainder Theorem (CRT), where the moduli are \(M_1, M_2, \ldots , M_k\) which are not necessarily pairwise coprime. If the errors of the corrupted remainders are within \(\tau = \displaystyle \max _{1\le i\le k} \min _{{\mathop {j\ne i}\limits ^{1\le j\le k}}} \frac{\gcd (M_i,M_j)}{4}\), their schemes can be used to construct an approximation of the solution to the generalized CRT with an error smaller than \(\tau \). Accurately finding the quotients is a critical ingredient in their approach. In this paper, we shall start with a faithful historical account of the generalized CRT. We then present two treatments of the problem of solving generalized CRT with erroneous remainders. The first treatment follows the route of Wang and Xia to find the quotients, but with a simplified process. The second treatment considers a simplified model of generalized CRT and takes a different approach by working on the corrupted remainders directly. This approach also reveals some useful information about the remainders by inspecting extreme values of the erroneous remainders modulo \(4\tau \). Both of our treatments produce efficient algorithms with essentially optimal performance. Finally, this paper constructs a counterexample to prove the sharpness of the error bound \(\tau \).

Due to its remarkable performance and potential resistance to quantum attacks, \(\mathsf {NTRUEncrypt}\) has drawn much attention recently; it also has been standardized by IEEE. However, classical \(\mathsf {NTRUEncrypt}\) lacks a strong security guarantee and its security still relies on heuristic arguments. At Eurocrypt 2011, Stehle and Steinfeld first proposed a variant of \(\mathsf {NTRUEncrypt}\) with a security reduction from standard problems on ideal lattices. This variant is restricted to the family of rings \(\mathbb {Z}[X]/(X^n+1)\) with n a power of 2 and its private keys are sampled by rejection from certain discrete Gaussian so that the public key is shown to be almost uniform. Despite the fact that partial operations, especially for \(\mathsf {RLWE} \), over \(\mathbb {Z}[X]/(X^n+1)\) are simple and efficient, these rings are quite scarce and different from the classical \(\mathsf {NTRU}\) setting. In this work, we consider a variant of \(\mathsf {NTRUEncrypt}\) over prime cyclotomic rings, i.e. \(\mathbb {Z}[X]/(X^{n-1}+\cdots +X+1)\) with n an odd prime, and obtain \(\mathsf {IND\text {-}CPA}\) secure results in the standard model assuming the hardness of worst-case problems on ideal lattices. In our setting, the choice of the rings is much more flexible and the scheme is closer to the original \(\mathsf {NTRU}\), as \(\mathbb {Z}[X]/(X^{n-1}+\cdots +X+1)\) is a large subring of the \(\mathsf {NTRU}\) ring \(\mathbb {Z}[X]/(X^{n}-1)\). Some tools for prime cyclotomic rings are also developed.

This paper considers efficient scalar multiplication of elliptic curves over binary fields with a twofold purpose. Firstly, we derive the most efficient 3P formula in \(\lambda \)-projective coordinates and 5P formula in both affine and \(\lambda \)-projective coordinates. Secondly, extensive experiments have been conducted to test various multi-base scalar multiplication methods (e.g., greedy, ternary/binary, multi-base NAF, and tree-based) by integrating our fast formulas. The experiments show that our 3P and 5P formulas had an important role in speeding up the greedy, the ternary/binary, the multi-base NAF, and the tree-based methods over the NAF method. We also establish an efficient 3P formula for Koblitz curves and use it to construct an improved set for the optimal pre-computation of window TNAF.

As a new network architecture and key technology of 5G, Network Function Virtualization (NFV) is paid special attention in both industry and academia. In the context of NFV, Virtualized Network Functions (VNFs) located in different network computing platforms need collaborate to fulfill an expected networking service. Platform trust authentication and trusted collaboration should be highly ensured in order to support secure and trustworthy 5G mobile networks and wireless systems. However, such a mechanism is still missed in the literature. In this paper, we propose and develop a trust insurance mechanism, named TIM, based on Trusted Computing Platform (TCP) to realize trust authentication and achieve trusted collaboration among VNFs. Performance evaluation shows the effectiveness of TIM with regard to trust attestation accuracy, operation efficiency, and reasonable resource consumption.

The most abundantly produced virion protein in human cytomegalovirus (HCMV) is the immunodominant phosphoprotein 65 (pp65), which is frequently included in CMV vaccines. Although it is nonessential for in vitro CMV growth, pp65 displays immunomodulatory functions that support a potential role in primary and/or persistent infection. To determine the contribution of pp65 to CMV infection and immunity, we generated a rhesus CMV lacking both pp65 orthologs (RhCMVΔpp65ab). While deletion of pp65ab slightly reduced growth in vitro and increased defective particle formation, the protein composition of secreted virions was largely unchanged. Interestingly, pp65 was not required for primary and persistent infection in animals. Immune responses induced by RhCMVΔpp65ab did not prevent reinfection with rhesus CMV; however, reinfection with RhCMVΔUS2-11, which lacks viral-encoded MHC-I antigen presentation inhibitors, was prevented. Unexpectedly, induction of pp65b-specific T cells alone did not protect against RhCMVΔUS2-11 challenge, suggesting that T cells targeting multiple CMV antigens are required for protection. However, pp65-specific immunity was crucial for controlling viral dissemination during primary infection, as indicated by the marked increase of RhCMVΔpp65ab genome copies in CMV-naive, but not CMV-immune, animals. Our data provide rationale for inclusion of pp65 into CMV vaccines but also demonstrate that pp65-induced T cell responses alone do not recapitulate the protective effect of natural infection.

In CRYPTO 2009, Lyubashevsky and Micciancio presented reductions BDD 1 / 2 γ (Bounded Distance Decoding Problem) ≤ uSVP γ (Unique Shortest Vector Problem) ≤ BDD 1 / γ , and posed an open problem whether the reduction gap can be closed. This paper concerns bounded distance decoding (BDD) problems for lattices with large λ 2 -gap. In the presence of larger λ 2 -gap, better reductions from BDD to uSVP and exact SVP are obtained. Some result can be regarded as a partial solution to the open problem. For some parameters, a better reduction from BDD to uSVP is given.An open problem proposed by Lyubashevsky and Micciancio is partially solved.This paper also improves a previous reduction from BDD to exact SVP.

Inspired by an interesting idea of Cai and Zhang, we formulate and prove the convex k-sparse decomposition of vectors that is invariant with respect to the l 1 norm. This result fits well in discussing compressed sensing problems under the Restricted Isometry property, but we believe it also has independent interest. As an application, a simple derivation of the RIP recovery condition δ k +θ k,k

Cytomegalovirus (CMV) induces strong and long-lasting immune responses, which make it an attractive candidate for a cancer vaccine vector. In this study, we tested whether a tumor antigen expressed in CMV can induce a strong anti-tumor effect. We expressed an unmodified melanoma antigen, mouse tyrosinase-related protein 2 (TRP2), in mouse cytomegalovirus (MCMV). Prophylactic vaccination of the mice with a single dose of MCMV-TRP2 induced rejection of B16 melanoma challenge; therapeutic vaccination with MCMV-TRP2 prolonged the survival of the mice challenged with B16 cells. Additionally, vaccination with MCMV-TRP2 five months before tumor challenge still induced tumor rejection, which indicated that the vaccine induced long-term protection. Furthermore, MCMV-TRP2 protected mice against B16 melanoma challenge regardless of the pre-existing CMV infection. We found that vaccination with MCMV-TRP2 induced long-lasting TRP2 specific antibodies but not CD8 T cells. In addition, depletion of CD4 and CD8 T cells did not compromise the antitumor effect by MCMV-TRP2; while in B cell deficient (μMT) mice, the vaccine lost its antitumor effect. These results indicate that antibodies, not T cells, are important in mediating the antitumor effect during the effector phase by the vaccine. We also made a spread deficient MCMV-TRP2 lacking the essential glycoprotein gL, which showed a similar antitumor effect. In conclusion, our study indicates that tumor antigen (TRP2) expressed in MCMV induces a strong and long-lasting anti-melanoma effect through an antibody-dependent mechanism. Our findings demonstrate that CMV might be a promising vector for the development of cancer vaccines.

This paper concerns the hardness of approximating the closest vector in a lattice with preprocessing in l 1 norm, and gives a polynomial time algorithm for GapCVPPγ in l 1 norm with gap γ = O(n/logn). The gap is smaller than that obtained by simply generalizing the approach given by Aharonov and Regev. The main technical ingredient used in this paper is the discrete Laplace distribution on lattices which may be of independent interest.

The RNA-binding protein AUF1 binds AU-rich elements in 3'-untranslated regions to regulate mRNA degradation and/or translation. Many of these mRNAs are predicted microRNA targets as well. An emerging theme in post-transcriptional control of gene expression is that RNA-binding proteins and microRNAs co-regulate mRNAs. Recent experiments and bioinformatic analyses suggest this type of co-regulation may be widespread across the transcriptome. Here, we identified mRNA targets of AUF1 from a complex pool of cellular mRNAs and examined a subset of these mRNAs to explore the links between RNA binding and mRNA degradation for both AUF1 and Argonaute 2 (AGO2), which is an essential effector of microRNA-induced gene silencing. Depending on the specific mRNA examined, AUF1 and AGO2 binding is proportional/cooperative, reciprocal/competitive or independent. For most mRNAs in which AUF1 affects their decay rates, mRNA degradation requires AGO2. Thus, AUF1 and AGO2 present mRNA-specific allosteric binding relationships for co-regulation of mRNA degradation.

Cytomegalovirus is an attractive cancer vaccine platform because it induces strong, functional CD8(+) T-cell responses that accumulate over time and migrate into most tissues. To explore this, we used murine cytomegalovirus expressing a modified gp100 melanoma antigen. Therapeutic vaccination by the intraperitoneal and intradermal routes induced tumor infiltrating gp100-specific CD8(+) T-cells, but provided minimal benefit for subcutaneous lesions. In contrast, intratumoral infection of established tumor nodules greatly inhibited tumor growth and improved overall survival in a CD8(+) T-cell-dependent manner, even in mice previously infected with murine cytomegalovirus. Although murine cytomegalovirus could infect and kill B16F0s in vitro, infection was restricted to tumor-associated macrophages in vivo. Surprisingly, the presence of a tumor antigen in the virus only slightly increased the efficacy of intratumoral infection and tumor-specific CD8(+) T-cells in the tumor remained dysfunctional. Importantly, combining intratumoral murine cytomegalovirus infection with anti-PD-L1 therapy was synergistic, resulting in tumor clearance from over half of the mice and subsequent protection against tumor challenge. Thus, while a murine cytomegalovirus-based vaccine was poorly effective against established subcutaneous tumors, direct infection of tumor nodules unexpectedly delayed tumor growth and synergized with immune checkpoint blockade to promote tumor clearance and long-term protection.