Designer Primes

Prime integers are the backbone of most public key cryptosystems. Attacks often go after the primes themselves, as in the case of all factoring and index calculus algorithms. Primes are time sensitive cryptographic material and should be periodically changed. Unfortunately many systems use fixed primes for a variety of reasons, including the difficulty of generating trusted, random, cryptographically secure primes. This is particularly concerning in the case of discrete log based cryptosystems. This paper describes a variant of provable prime generation, intended for discrete logarithm based cryptography, based off Pocklington\u27s theorem with improved efficiency, flexibility and security

Prime Proof Protocol

Prime integers form the basis for finite field and elliptic curve cryptography, as well as many other applications. Provable prime generation guarantees primality and is more efficient than probabilistic generation, and provides components for an efficient primality proof. This paper details a protocol which takes in the proof components from the generation process, proves primality, and as an added benefit, supplies the user with a subgroup generator

Da Yan Concentrator and Extender of Random Data (DYCE)

DYCE is a simple to analyze algorithm which converts raw entropy into usable cryptographic entropy using the Da Yan (commonly known as the ‘Chinese Remainder Theorem’). This paper describes and analyzes DYCE, giving its detailed algorithmic description

The effect of stress fracture occurring within the first 12 months of training on subsequent race performance in Thoroughbreds in Hong Kong

BACKGROUND Racehorses are at an increased risk of stress fracture within the first 12 months of racing and when resuming training after a break. Research in these high-risk periods and on the effect of performance post-recovery is limited. OBJECTIVES To describe the occurrence of stress fractures, diagnosed by nuclear scintigraphy (NS), in racehorses' first 12 months training in Hong Kong, and their impact on racing performance and career length. STUDY DESIGN Retrospective 1:2 matched case-control study. METHODS Clinical records of horses with NS-diagnosed stress fractures within 365 days of import between 2006 and 2018 were collated. Cases and controls were matched on import date. Univariable conditional logistic regression compared signalment, pre-fracture training and post-recovery racing performance between cases and matched controls. Shared Frailty Cox regression analysed time from import to fracture and total career length. RESULTS Eighty-seven horses sustained a NS-diagnosed fracture within their first year in Hong Kong (incidence risk 1.7% (95% confidence interval (CI) 1.4-2.1%; N=5,180)). The humerus (42.0%; 95% CI 31.8-52.6%; n=39) and tibia (28.0%; 95% CI 19.1-38.2%; n=26) were most common stress fracture sites. Cases missed a median of 63 days (Interquartile range (IQR) 49-82) of training because of fracture. Within the 12 months following diagnosis, case horses had a median of four (IQR 2-4, p<0.0001) fewer race starts and were down HK$206,188 (IQR HK$0-436,800, p=0.007) in race earnings compared to controls. Career length did not significantly differ between cases and controls (median 2 years and 3 months; IQR 15.3-39.1 months; p=0.2). MAIN LIMITATIONS Only stress fractures diagnosed by NS were included, hence, the study is not representative of all stress fractures occurring in racehorses in Hong Kong. CONCLUSIONS Racehorses sustaining a stress fracture within one year of entering Hong Kong lost significant time in training, earnings and race starts. However, overall career length was unaffected

Flux and Seasonality of Dissolved Organic Matter From the Northern Dvina (Severnaya Dvina) River, Russia

Pan‐Arctic riverine dissolved organic carbon (DOC) fluxes represent a major transfer of carbon from land‐to‐ocean, and past scaling estimates have been predominantly derived from the six major Arctic rivers. However, smaller watersheds are constrained to northern high‐latitude regions and, particularly with respect to the Eurasian Arctic, have received little attention. In this study, we evaluated the concentration of DOC and composition of dissolved organic matter (DOM) via optical parameters, biomarkers (lignin phenols), and ultrahigh resolution mass spectrometry in the Northern Dvina River (a midsized high‐latitude constrained river). Elevated DOC, lignin concentrations, and aromatic DOM indicators were observed throughout the year in comparison to the major Arctic rivers with seasonality exhibiting a clear spring freshet and also some years a secondary pulse in the autumn concurrent with the onset of freezing. Chromophoric DOM absorbance at a350 was strongly correlated to DOC and lignin across the hydrograph; however, the relationships did not fit previous models derived from the six major Arctic rivers. Updated DOC and lignin fluxes were derived for the pan‐Arctic watershed by scaling from the Northern Dvina resulting in increased DOC and lignin fluxes (50 Tg yr−1 and 216 Gg yr−1, respectively) compared to past estimates. This leads to a reduction in the residence time for terrestrial carbon in the Arctic Ocean (0.5 to 1.8 years). These findings suggest that constrained northern high‐latitude rivers are underrepresented in models of fluxes based from the six largest Arctic rivers with important ramifications for the export and fate of terrestrial carbon in the Arctic Ocean

Matched and Mismatched Cognitive Appraisals in Patients with Breast Cancer and their Partners: Implications for Psychological Distress

The present study sought to identify couples’ cognitive appraisals of breast cancer and the extent to which matched or mismatched appraisals within a couple contribute to distress. Women with breast cancer (n = 57) and their partners completed the Cognitive Appraisals of Health Scale along with two self-report measures of distress, the Profile of Mood States and the Impact of Events Scale. Four groups were created based on their cognitive appraisals. Couples where both patient and partner scored highest on challenge or benign appraisals formed the positive outlook group (P+S+); when both scored highest on threat or harm/loss they formed the negative outlook group (P-S-). In the mismatched groups the patient had a positive outlook and their partner had a negative outlook (P+S-), or vice versa (P-S+). In general, lower distress was related to participants’ own positive outlook. Higher distress for patients was found in the matched group P-S-; for partners it was found in the mismatched group P+S-. These findings suggest partner effects for both patients and partners. When the patient had a negative outlook, a partner negative outlook was associated with the highest psychological distress. When the partner had a negative outlook, a patient positive outlook was associated with the highest psychological distress. There are several possible explanations for these findings, each with different implications for clinical practice. Future research with different groups of cancer patients and longitudinal, mixed methods designs may clarify their meaning

Comprehensive Solid-State Characterization of Rare Earth Flouride Nanoparticles

The combination of multinuclear solid-state NMR spectroscopy and powder X-ray diffraction has been applied to characterize the octahedron-shaped crystalline nanoparticle products resulting from an inverse micelle synthesis. Rietveld refinements of the powder X-ray diffraction data from the nanoparticles revealed their general formula to be (H3O)Y3F10·xH2O. 1H magic-angle spinning (MAS) NMR experiments provided information on sample purity and served as an excellent probe of the zeolithic incorporation of atmospheric water. 19F MAS NMR experiments on a series of monodisperse nanoparticle samples of various sizes yielded spectra featuring three unique 19F resonances arising from three different fluorine sites within the (H3O)Y3F10·xH2O crystal structure. Partial removal of zeolithic water from the internal cavities and tunnels of the nanoparticles led to changes in the integrated peak intensities in the 19F MAS NMR spectra; the origin of this behavior is discussed in terms of 19F longitudinal relaxation. 19F–89Y variable-amplitude cross-polarization (VACP) NMR experiments on both stationary samples and samples under MAS conditions indicated that two distinct yttrium environments are present, and on the basis of the relative peak intensities, the population of one of the two sites is closely linked to the nanoparticle size. Both 19F MAS and 19F–89Y VACP/MAS experiments indicated small amounts of an impurity present in certain nanoparticles; these are postulated to be spherical amorphous YF3 nanoparticles. We discuss the importance of probing molecular-level structure in addition to microscopic structure and how the combination of these characterization methods is crucial for understanding nanoparticle design, synthesis, and application

Recombination:The good, the bad and the variable

International audienc