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Mersenne Numbers: consolidated results
This document provides and comments on the results of the Lucas-Lehmer testing and/or partial factorisation of all Mersenne Numbers Mp = 2^p-1 where p is prime and less than 100,000. Previous computations have either been confirmed or corrected.
The LLT computations on the ICL DAP is the first implementation of Fast-Fermat-Number-Transform multiplication in connection with Mersenne Number testing.
This paper championed the disciplines of systematically testing the Mp, and of double-sourcing results which were not manifestly correct. Both disciplines were adopted by the later GIMPS initiative, the 'Great Internet Mersenne Prime Search, which was itself one of the first web-based distributed-community projects
Neuroretinitis following bull ant sting
Cat scratch disease causes the majority of cases of neuroretinitis. Neuroretinitis is characterised by clinical features of papillitis, macular oedema and macular star. We report a case study of infection with Bartonella henselae most likely transmitted by a bull ant sting. The patient presented with blurred vision and reduced visual acuity after being stung by an ant in her garden some 7 days earlier. Further testing revealed positive serology to B henselae and the patient improved with appropriate treatment
TRIM63 (MuRF-1) Gene Polymorphism is Associated with Biomarkers of Exercise-Induced Muscle Damage
Unaccustomed strenuous exercise can lead to muscle strength loss, inflammation and delayed onset muscle soreness, which may be influenced by genetic variation. We investigated if a missense single nucleotide polymorphism (A>G, rs2275950) within the TRIM63 gene (encoding MuRF-1 and potentially affecting titin mechanical properties) was associated with the variable response to unaccustomed eccentric exercise. Sixty-five untrained, healthy participants (genotyped for rs2275950: AA, AG and GG) performed 120 maximal eccentric knee extensions (ECC) to induce muscle damage. Isometric and isokinetic maximal voluntary knee extension contractions (MVCs) and muscle soreness were assessed before, immediately after, and 48h after ECC. AA homozygotes were consistently stronger [baseline isometric MVC: 3.23±0.92 Nm/kg (AA) vs. 2.09±0.67 Nm/kg (GG); p=0.006] and demonstrated less muscle soreness over time (p=0.022) compared to GG homozygotes. This may be explained by greater titin stiffness in AA homozygotes, leading to intrinsically stronger muscle fibers that are more resistant to eccentric damaging contractions
Review of the prevalence of diabetic retinopathy in Indigenous Australians
Author version made available in accordance with Publisher copyright policy.The purpose of this review is to compare the prevalence of diabetic retinopathy (DR) between Indigenous and non-Indigenous Australians with Diabetes Mellitus (DM). Australian DR prevalence data from 6 Indigenous studies (n = 2865) and 5 non-Indigenous studies (n = 9801) conducted between 1985 and 2013 were included for analysis. Estimated prevalence of any DR among Indigenous Australians with DM was 23.4% compared with 28.9% for non-Indigenous Australians (χ2 = 26.9, P < 0.001). In studies performed after 1990, a significantly higher rate of diabetic macular edema was found in Indigenous compared with non-Indigenous Australians with DM (7.6% versus 4.9%, χ2 = 6.67, P = 0.01). Although there are limitations in comparing these studies, one explanation for the observed data could be a model in which Indigenous Australians are relatively resistant to early stage DR, but with a subset progressing to sight threatening DR due to individual genetic and environmental susceptibility factors coupled with poor glycemic control
Intraocular Chemotherapy for Vitreoretinal Lymphoma: a review
© 2019 Royal Australian and New Zealand College of OphthalmologistsVitreoretinal lymphomas are rare ocular cancers, and the subset of primary central nervous system lymphomas that are based in the posterior eye. These tumours are challenging to treat, and today management generally involves a multispecialty team coordinating a treatment protocol that may include intraocular chemotherapy, ocular irradiation, systemic chemotherapy and/or autologous stem cell transplantation. The ophthalmologist has specific responsibility for the intraocular chemotherapy, which is delivered to the eye by intravitreal injection. The most commonly injected drugs are methotrexate—an anti‐metabolite—and rituximab—an anti‐human B cell monoclonal antibody. A range of intraocular chemotherapy treatment schedules have been described in the medical literature, although to date there have been no randomized clinical trials of these schedules. In this article, we review the development and current status of intraocular chemotherapy for vitreoretinal lymphoma
Polygenic mechanisms underpinning the response to exercise-induced muscle damage in humans:In vivo and in vitro evidence
We investigated whether 20 candidate single nucleotide polymorphisms (SNPs) were associated with in vivo exercise-induced muscle damage (EIMD), and with an in vitro skeletal muscle stem cell wound healing assay. Sixty-five young, untrained Caucasian adults performed 120 maximal eccentric knee-extensions on an isokinetic dynamometer to induce EIMD. Maximal voluntary isometric/isokinetic knee-extensor torque, knee joint range of motion (ROM), muscle soreness, serum creatine kinase activity and interleukin-6 concentration were assessed before, directly after and 48 h after EIMD. Muscle stem cells were cultured from vastus lateralis biopsies from a separate cohort (n = 12), and markers of repair were measured in vitro. Participants were genotyped for all 20 SNPs using real-time PCR. Seven SNPs were associated with the response to EIMD, and these were used to calculate a total genotype score, which enabled participants to be segregated into three polygenic groups: ‘preferential’ (more ‘protective’ alleles), ‘moderate’, and ‘non-preferential’. The non-preferential group was consistently weaker than the preferential group (1.93 ± 0.81 vs. 2.73 ± 0.59 N ∙ m/kg; P = 9.51 × 10−4) and demonstrated more muscle soreness (p = 0.011) and a larger decrease in knee joint ROM (p = 0.006) following EIMD. Two TTN-AS1 SNPs in linkage disequilibrium were associated with in vivo EIMD (rs3731749, p ≤ 0.005) and accelerated muscle stem cell migration into the artificial wound in vitro (rs1001238, p ≤ 0.006). Thus, we have identified a polygenic profile, linked with both muscle weakness and poorer recovery following EIMD. Moreover, we provide evidence for a novel TTN gene-cell-skeletal muscle mechanism that may help explain some of the interindividual variability in the response to EIMD.</p
A new approach to spherically symmetric junction surfaces and the matching of FLRW regions
We investigate timelike junctions (with surface layer) between spherically
symmetric solutions of the Einstein-field equation. In contrast to previous
investigations this is done in a coordinate system in which the junction
surface motion is absorbed in the metric, while all coordinates are continuous
at the junction surface.
The evolution equations for all relevant quantities are derived. We discuss
the no-surface layer case (boundary surface) and study the behaviour for small
surface energies. It is shown that one should expect cases in which the speed
of light is reached within a finite proper time.
We carefully discuss necessary and sufficient conditions for a possible
matching of spherically symmetric sections.
For timelike junctions between spherically symmetric space-time sections we
show explicitly that the time component of the Lanczos equation always reduces
to an identity (independently of the surface equation of state).
The results are applied to the matching of FLRW models. We discuss `vacuum
bubbles' and closed-open junctions in detail. As illustrations several
numerical integration results are presented, some of them indicate that the
junction surface can reach the speed of light within a finite time.Comment: new version - corrected boundary surface discussion, improved
presentation, and corrected reference 22 pages, many figure
Physical Acceptability of Isolated, Static, Spherically Symmetric, Perfect Fluid Solutions of Einstein's Equations
We ask the following question: Of the exact solutions to Einstein's equations
extant in the literature, how many could represent the field associated with an
isolated static spherically symmetric perfect fluid source? The candidate
solutions were subjected to the following elementary tests: i) isotropy of the
pressure, ii) regularity at the origin, iii) positive definiteness of the
energy density and pressure at the origin, iv) vanishing of the pressure at
some finite radius, v) monotonic decrease of the energy density and pressure
with increasing radius, and vi) subluminal sound speed. A total of 127
candidate solutions were found. Only 16 of these passed all the tests. Of these
16, only 9 have a sound speed which monotonically decreases with radius. The
analysis was facilitated by use of the computer algebra system GRTensorII.Comment: 25 pages. To appear in Computer Physics Communications Thematic Issue
on "Computer Algebra in Physics Research
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