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The ring learning with errors (RLWE) problem can be used to construct efficient post-quantum public key encryption schemes. An error distribution, normally a Gaussian-like distribution, is involved in the RLWE problem. In this work we focus on using polar codes to alleviate a natural trade-off present in RLWE public key encryption schemes; namely, we would like a wider error distribution to increase security, but a wider error distribution comes at the cost of an increased probability of decryption error. The motivation of this work is to improve the bit-security level by using wider error distribution while keeping the target decryption failure rate achievable. The approach we proposed in this work is twofold. Firstly, we formulate RLWE public key encryption as a channel model with some noise terms known by the decoder. This makes our approach distinguished from existing research of this kind in the literature which ignores these known terms. Secondly, we design polar codes for the derived channel model. Theoretically and numerically, we show the proposed modeling and polar coding scheme contributes to a considerable bit-security level improvement compared with NewHope, a submission to National Institute of Standards and Technology (NIST), with almost the same parameters. Moreover, polar encoding and decoding support isochronous implementations in the sense that the timings of associated operations are irrelevant to the sensitive information.

Promoting endothelial cell (EC) proliferation and angiogenesis after indirect revascularization surgery is crucial for decreasing the stroke rate in moyamoya patients. However, the role of delta-like factor 1 (DLK1) in regulating EC proliferation in chronically ischaemic brains and the specific mechanisms remain unclear. Therefore, we compared the expression levels of DLK1 in the dura mater (DM) tissues of patients with moyamoya disease and patients with aneurysms, and dual luciferase reporter and RNA binding protein immunoprecipitation assays were conducted to determine whether DLK1 is a target gene of miR-126-5p. The effect of DLK1 on EC proliferation and the interaction between DLK1 and miR-126-5p were explored in vitro. Then, we established an animal model of two-vessel occlusion together with encephalo-myo-synangiosis (2VO+EMS). The temporalis muscles (TMs) of the animals were transfected with DLK1 lentiviral RNA (Lv-DLK1) and short hairpin RNA (sh-DLK1) to compare the DLK1 expression, angiogenesis (CD31 count), and numbers of vacuoles and impaired tight junctions in the ECs of TM-covered chronically ischaemic brains as well as the cognitive improvement in each group. DLK1 expression was lower in the DM tissues of moyamoya patients than in those of the aneurysm patients, and DLK1 was identified as a target gene of miR-126-5p. In vitro, DLK1 inhibited EC proliferation, migration and angiogenesis and exerted effects opposite those of miR-126-5p. In 2VO+EMS rats, compared to the control transfection, the TM transfection of Lv-DLK1 induced significantly higher DLK1 expression and worse angiogenesis in the TM-covered ischaemic brain as well as less extensive cognitive improvement, while the transfection of sh-DLK1 into the TM had the opposite effects. In summary, DLK1, a target gene of miR-126-5p, negatively regulates angiogenesis in chronically ischaemic brains and is expected to be a new target to improve the efficacy of indirect revascularization surgery and the prognosis of moyamoya patients.

With the development of urban rail transit systems, the operation and management of the system faces various problems, among which the unreasonably long waiting time at transfer stations during the first train period is a major challenge for metro companies. To address this problem, some cities (e.g. Guangzhou, Hefei) are operating inter-regional trains to reduce the waiting time of passengers. With this motivation, we study the first train timetable synchronization problem with multiple departure stations. The problem is first formulated as a mixed integer nonlinear programming (MINLP) model. By using auxiliary intermediate variables, the nonlinear model is reformulated as a mixed integer linear programming (MILP) model, which can be solved directly by the commercial solver COPT. A real-world example of the Hefei urban rail transit network is applied to test the effectiveness of the proposed model. By adjusting the first ordinary train start service times and operating 12 additional inter-regional trains on 2 bidirectional lines, the total transfer waiting time and the number of long waiting time directions decreased by 39.09% and 56.25%, respectively.

Cryptographic constructions based on hard lattice problems have emerged as a front runner for the standardization of post-quantum public-key cryptography. As the standardization process takes place, optimizing specific parts of proposed schemes, e.g., Bernoulli sampling and integer Gaussian sampling, becomes a worthwhile endeavor. In this work, we propose a novel Bernoulli sampler based on polar codes, dubbed “polar sampler”. The polar sampler is information theoretically optimum in the sense that the number of uniformly random bits it consumes approaches the entropy bound asymptotically. It also features quasi-linear complexity and constant-time implementation. An integer Gaussian sampler is developed using multilevel polar samplers. Our algorithm becomes effective when sufficiently many samples are required at each query to the sampler. Security analysis is given based on Kullback–Leibler divergence and Rényi divergence. Experimental and asymptotic comparisons between our integer Gaussian sampler and state-of-the-art samplers verify its efficiency in terms of entropy consumption, running time and memory cost. We envisage that the proposed Bernoulli sampler can find other applications in cryptography in addition to Gaussian sampling.

Weiran Xu,1,&ast; Xiling Hu,2,&ast; Xing Zhang,3 Cong Ling,4 Chaofan Wang,5 Lingling Gao1 1School of Nursing, Sun Yat-sen University, Guangzhou, People’s Republic of China; 2Department of Medicine, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People’s Republic of China; 3Department of Endocrinology and Metabolism, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, People’s Republic of China; 4Department of Neurosurgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People’s Republic of China; 5Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Lingling Gao Email gaoll@mail.sysu.edu.cnObjective: This study investigated the biomedical, psychological, and social behavior risk factors for cognitive impairment in middle-aged and elderly patients with type 2 diabetes mellitus (T2DM).Methods: This cross-sectional study included 240 patients with T2DM. A questionnaire was used to collect demographic and disease-related data on patients, and the Self-rating Depression Scale (SDS), Diabetes Self-care Scale (DSCS), and Social Support Rating Scale (SSRS) were used to assess patients’ depression status, self-management behavior, and social support, respectively. The Chinese version of the Montreal Cognitive Assessment (MoCA) was used to evaluate cognitive function, with a score < 26 set as the threshold for cognitive impairment.Results: The prevalence of cognitive dysfunction in middle-aged and elderly patients with T2DM was 52.5%. Multivariate logistic regression analysis showed that older age, a history of hypoglycemia within 1 month, and depression were independent risk factors for cognitive impairment. Education for > 12 years, urban living, and a higher total score on the DSCS were independent protective factors against cognitive impairment.Conclusion: T2DM patients with high risk of cognitive impairment can be identified early from the bio-psycho-social perspective. Patients with T2DM who are older, less educated, living in rural areas, have hypoglycemia history, and have poor self-management of diabetes are at increased risk of cognitive impairment. Closer monitoring of patients with hypoglycemia, early detection of depression, and improving patients’ self-management capacity can prevent cognitive impairment in middle-aged and elderly patients with T2DM.Keywords: type 2 diabetes mellitus, cognitive impairment, depression, self-care, social support

Xiling Hu,1,&ast; Yao Zhang,2,&ast; Bin Yao,2 Beisi Lin,2 Dan Yang,3 Cong Ling,4,&ast; Lingling Gao3,&ast; 1Department of Medicine, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People’s Republic of China; 2Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People’s Republic of China; 3School of Nursing, Sun Yat-sen University, Guangzhou, People’s Republic of China; 4Department of Neurosurgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Cong LingDepartment of Neurosurgery, The Third Affiliated Hospital of Sun Yat-sen University, No. 600 Tianhe Road, Guangzhou, Guangdong, 510630, People’s Republic of ChinaTel +86-13580465121Email doctor200@126.comLingling GaoSchool of Nursing, Sun Yat-sen University, No. 74, Zhongshan Er Road, Guangzhou, Guangdong, 510085, People’s Republic of ChinaTel +86 13539965693Email gaoll@mail.sysu.edu.cnPurpose: The purpose of this exploratory qualitative study was to identify the needs and barriers to diabetes dietary education issues in a Chinese context among people with type 2 diabetes and also their family members.Patients and Methods: Nineteen patients with type 2 diabetes and 15 family members were randomly selected from a larger study in Guangzhou. Descriptive phenomenological qualitative inquiry guided this study.Results: Both patients and their family members claimed a variety of needs regarding diabetes dietary information and that it should be patient-centered. In addition, both groups identified the effectiveness and helpfulness of diabetes diet-related health education, but family members reported a lack of professional education. Patients reported that the barriers to diabetes diet-related health education were: 1) patients’ different faculties of memory and acceptance, 2) educators’ methods of explaining the information, 3) lack of advertising and intensity of publicity both inside and outside of the hospital. Family members identified that diabetes diet-related health education assisted them with taking care of patients with diabetes and it was also beneficial for themselves to gain more dietary knowledge and develop healthy dietary habits.Conclusion: It is necessary to make some adjustment to traditional diabetes dietary education. It may be a good strategy to investigate the needs and faculties of memory and acceptance of people with diabetes before starting a diabetes education program. Hospitals should intensify their publicity of diabetes education and make it more attractive to patients with diabetes and their family members. Educators should add information specifically for family members while conducting diabetes education. Tertiary hospitals could provide standardized training regarding diabetes-related health education to community family physicians; in this way, diabetes education could gradually be transferred to them and both groups of clinicians could share in the education.Keywords: diabetes, family members, dietary education, needs, barriers, qualitative

Background: Cryptococcal meningitis (CM) combined with intracranial hypertension is associated with a poor prognosis. This study aimed to investigate the therapeutic efficacy and prognostic factor of ventriculo-peritoneal(V-P) shunt in the non-human immunodeficiency virus (HIV) CM patients withintracranial hypertension. Methods: A total of 136non-HIV CM patients with intracranial hypertension treated in our hospital from July 2010 to December 2019 wereretrospectively included. Fifty-seven patients underwent V-P shunt placement (the Shunt group) and 79 patients received conservative therapy (the conservative group). The clinical symptoms after treatment, the cerebrospinal fluid (CSF) tests results andtherapeutic outcomes were compared between the groups. Results: V-P shunt significantly reduced the incidences of headache, vomiting, cranial nerve injury, the intracranial pressure, and CSF leukocyte level in CM patients (all PConclusion: Our results suggested that V-P shunt is an effective and safe treatment for non-HIV CM patients combined with intracranial hypertension. Seroconversion time was the only independent factor associated with the survival outcome.

Guidewire retention during an interventional treatment is a very rare complication that can lead to possible serious complications, such as thrombosis, embolization, sepsis, and perforation. Hence, a retained guidewire must be retrieved as soon as possible. Here, we provide the first report of a case of accidental retention of a 0.035” J guidewire in the right atrium and aortic arch during basilar artery aneurysm embolization. We found that due to the heavier weight of the J guidewire and its hydrophilic-coated layer, it could not be removed using previously reported methods for micro-guidewire retention. Therefore, we constructed a self-invented snare device consisting of a 0.014” micro-guidewire and a 4-Fr MP-A1 catheter and successfully retrieved the J guidewire, thus avoiding open surgery and its associated serious complications. According to our experience, this novel technique described here is quite easy to perform, safe and effective and can avoid serious complications and prevent the need for open surgery.

The Learning with Errors (LWE) problem is the fundamental backbone of modern lattice-based cryptography, allowing one to establish cryptography on the hardness of well-studied computational problems. However, schemes based on LWE are often impractical, so Ring LWE was introduced as a form of ‘structured’ LWE, trading off a hard to quantify loss of security for an increase in efficiency by working over a well-chosen ring. Another popular variant, Module LWE, generalizes this exchange by implementing a module structure over a ring. In this work, we introduce a novel variant of LWE over cyclic algebras (CLWE) to replicate the addition of the ring structure taking LWE to Ring LWE by adding cyclic structure to Module LWE. We show that the security reductions expected for an LWE problem hold, namely a reduction from certain structured lattice problems to the hardness of the decision variant of the CLWE problem (under the condition of constant rank d). As a contribution of theoretic interest, we view CLWE as the first variant of Ring LWE which supports non-commutative multiplication operations. This ring structure compares favorably with Module LWE, and naturally allows a larger message space for error correction coding.

We propose a lattice-based scheme for secret key generation from Gaussian sources in the presence of an eavesdropper, and show that it achieves the strong secret key capacity in the case of degraded source models, as well as the optimal secret key / public communication rate trade-off. The key ingredients of our scheme are the use of the modulo lattice operation to extract the channel intrinsic randomness, based on the notion of flatness factor, together with a randomized lattice quantization technique to quantize the continuous source. Compared to previous works, we introduce two new notions of flatness factor based on $L^1$ distance and KL divergence, respectively, which might be of independent interest. We prove the existence of secrecy-good lattices under $L^1$ distance and KL divergence, whose $L^1$ and KL flatness factors vanish for volume-to-noise ratios up to $2\pi e$. This improves upon the volume-to-noise ratio threshold $2\pi$ of the $L^{\infty}$ flatness factor., Comment: 17 pages, 3 figures, accepted for publication in IEEE Trans. Inf. Theory

Congenital bilateral absence of the vas deferens (CBAVD) is observed in 1%-2% of males presenting with infertility and is clearly associated with cystic fibrosis transmembrane conductance regulator (CFTR) mutations. CFTR is one of the most well-known genes related to male fertility. The frequency of CFTR mutations or impaired CFTR expression is increased in men with nonobstructive azoospermia (NOA). CFTR mutations are highly polymorphic and have established ethnic specificity. Compared with F508Del in Caucasians, the p.G970D mutation is reported to be the most frequent CFTR mutation in Chinese patients with cystic fibrosis. However, whether p.G970D participates in male infertility remains unknown. Herein, a loss-of-function CFTR p.G970D missense mutation was identified in a patient with CBAVD and NOA. Subsequent retrospective analysis of 122 Chinese patients with CBAVD showed that the mutation is a common pathogenic mutation (4.1%, 5/122), excluding polymorphic sites. Furthermore, we generated model cell lines derived from mouse testes harboring the homozygous Cftr p.G965D mutation equivalent to the CFTR variant in patients. The Cftr p.G965D mutation may be lethal in spermatogonial stem cells and spermatogonia and affect the proliferation of spermatocytes and Sertoli cells. In spermatocyte GC-2(spd)ts (GC2) Cftr p.G965D cells, RNA splicing variants were detected and CFTR expression decreased, which may contribute to the phenotypes associated with impaired spermatogenesis. Thus, this study indicated that the CFTR p.G970D missense mutation might be a pathogenic mutation for CBAVD in Chinese males and associated with impaired spermatogenesis by affecting the proliferation of germ cells.

Sampling from the lattice Gaussian distribution has emerged as a key problem in coding and decoding while Markov chain Monte Carlo (MCMC) methods from statistics offer an effective way to solve it. In this paper, the sliced lattice Gaussian sampling algorithm is proposed to further improve the convergence performance of the Markov chain targeting at lattice Gaussian sampling. We demonstrate that the Markov chain arising from it is uniformly ergodic, namely, it converges exponentially fast to the stationary distribution. Meanwhile, the convergence rate of the underlying Markov chain is also investigated, and we show the proposed sliced sampling algorithm entails a better convergence performance than the independent Metropolis-Hastings-Klein (IMHK) sampling algorithm. On the other hand, the decoding performance based on the proposed sampling algorithm is analyzed, where the optimization with respect to the standard deviation $\sigma >0$ of the target lattice Gaussian distribution is given. After that, a judicious mechanism based on distance judgement and dynamic updating for choosing $\sigma $ is proposed for a better decoding performance. Finally, simulation results based on multiple-input multiple-output (MIMO) detection are presented to confirm the performance gain by the convergence enhancement and the parameter optimization.

In a majority of research on covert communications, knowledge about channel state information (CSI) of main channel and/or warden channel is assumed to be known or partially known. However, a covert user may not afford to perform channel estimation in practice, and acquiring the warden’s CSI is even impossible. In this paper, we investigate covert communications over non-coherent Rayleigh fading channels, in both i.i.d. fast fading and slow fading cases. We observe that the purpose of covert communication in many scenarios is to hide the existence of the sender, not the receiver. Therefore, we allow the receiver to work in full-duplex mode such that it can emit artificial noise (AN) while receiving signals simultaneously. We analyse the achievable covert rates with fixed and varying AN power and show that in both fast and slow fading cases, it is possible to achieve a positive covert rate. For the slow fading case, we further extend the proposed strategy to a multi-user scenario, in which multiple other users share the same spectral resource and cause interference at the warden. Extensive simulations are performed to verify the correctness of our analysis, which provide new insights on the AN design problem in non-coherent channels.