Design of a Cryptographically Secure Pseudo Random Number Generator with Grammatical Evolution

This work investigates the potential of evolving an initial seed with Grammatical Evolution (GE), for the construction of cryptographically secure (CS) pseudo-random number generator (PRNG). We harness the flexibility of GE as an entropy source for returning initial seeds. The initial seeds returned by GE demonstrate an average entropy value of 7.920261600000001 which is extremely close to the ideal value of 8. The initial seed combined with our proposed approach, control_flow_incrementor, is used to construct both, GE-PRNG and GE-CSPRNG.The random numbers generated with CSPRNG meet the prescribed National Institute of Standards and Technology (NIST) SP800-22 requirements. Monte Carlo simulations established the efficacy of the PRNG. The experimental setup was designed to estimate the value for pi, in which 100,000,000 random numbers were generated by our system and which resulted in returning the value of pi to 3.146564000, with a precision up to six decimal digits. The random numbers by GE-PRNG were compared against those generated by Python’s rand() function for sampling. The sampling results, when measured for accuracy against twenty-nine real world regression datasets, showed that GE-PRNG had less error when compared to Python’s rand() against the ground truths in seventeen of those, while there was no discernible difference in the remaining twelve.

Comparison of Prevalence of Degenerative Findings on Lumbar MRI among Sciatica Patients classified using the McKenzie Method.

Purpose To determine if the prevalence of degenerative findings on MRI differ between sciatica patients with radiating pain below the knee assigned into two groups by using the McKenzie method. Methods A comparative study of one hundred sciatica patients referred to the spine clinic at the hospital for specialist consultation to explore the need for surgery. Patients were classified into centralizers (CEN-group), in which leg pain is relieved in response to repeated specific exercises, and non-centralizers (Non-CEN-group), who have not responded. The latter have been shown to have surgery more often than patients in the CEN-group, hypothesized to have more progressed degenerative findings on MRI. Multiple lumbar MRI characteristics were scored and compared between the groups. Results There was a statistically significant difference in the degenerative findings between centralizers and non-centralizers, respectively: vertebral end-plate changes were 63% and 43%; mean (SD) Pfirrmann’s disc degeneration score was 12.8 (±3.5) and 10.6 (±3.8); and severity score of total damage was 12.0 (±3.5) and 10.1 (±3.8). The prevalence of disc prolapses were 76% in the CEN-group and 59% in the Non-CEN-group. Further, 75% in the CEN- group and 74% in the Non-CEN group had nerve root compression due to disc herniation with no statistically discernible difference between the groups. Conclusion Disc contour changes on MRI were similar between both groups as well as prevalence of nerve root compressions, but more progressed disc changes on MRI were found in centralizers than in non-centralizers. Thus, neither disc nor overall degenerative findings in sciatica patients can be used to determine types of radicular pain.

The Yin-yang of Serial Dependence Effects: Every Response is both an Attraction to the Prior Response and a Repulsion from the Prior Stimulus

Visual perceptual decisions can be altered by recent experience. In the “serial dependence” effect, participants’ responses to visual stimuli appear to be biased toward (i.e., attracted to) recently encountered stimuli. Fischer and Whitney (2014) proposed that serial dependence reflects a “continuity field” that promotes visual stability by biasing perception toward the recent past. However, when participants are relatively accurate on the prior trial, there is no discernible difference between attraction to the prior stimulus and attraction to the prior response. To tease apart these alternative explanations of the attraction effect, we developed two complementary analysis techniques that rely on participants’ naturally occurring errors on a trial-by-trial basis, identifying any effect of the prior stimulus and, separately, any effect of the prior response (i.e., each effect could be attractive, repulsive, or absent). Applying these techniques to serial dependence data from a new experiment and four previously published studies, including Fischer and Whitney’s, we found that serial dependencies reflect an attraction to the previous response and repulsion from the previous stimulus, with these effects cancelling each other to different degrees for different experiments. In no case did we find evidence of an attraction to the prior stimulus. These results are consistent with literatures that predate the serial dependence effect: Attraction to prior responses is routinely observed in a wide variety of paradigms and repulsion from prior stimuli is ubiquitous, such as in the tilt aftereffect.

Kompressionstherapie: Wie nach der Sklerosierungsbehandlung die besten Ergebnisse erzielt werden können

<b>Background:</b> Sclerotherapy is considered to be the method of choice for the treatment of telangiectatic varicose veins (C1 veins). Whereas the use of compression stockings after sclerotherapy is recommended, little is known about the impact of compression on the outcome of sclerotherapy. The aim of this study was to assess the influence of compression on the outcome of injection sclerotherapy of C1 varicose veins. <b>Methods:</b> There were 100 legs of 50 consecutive patients with chronic venous insufficiency (C1) included. After randomization per patient, both legs were treated with sclerotherapy in a predefined area of the thigh (measuring 100 cm²), followed by eccentric compression for 24 hours. Group A received no further compression, whereas group B was additionally equipped with compression stockings of 18 to 20 mm Hg above the ankle and continued wearing these for 1 week. Photodocumentation was performed before, 1 week after, and 4 weeks after sclerotherapy, and the clinical outcome was assessed at these postprocedure follow-up dates. The photographs were reviewed by an internal unblinded rater and an independent blinded external rater. <b>Results:</b> There was no discernible difference between the groups in terms of clinical outcome or side effects after 4 weeks. Whereas inter-rater reliability was high, there was no correlation between the raters and patients in terms of outcome. In 55% of the treated legs, the patients deemed the result of the treatment to be good; in 27% of the treated legs, fair; and in 18%, poor. Postprocedure hyperpigmentation occurred in 13% of patients and was comparable in both groups. Compression therapy was found to be comfortable by the majority (58%) of patients. <b>Conclusions:</b> One week of postinterventional compression therapy had no clinical benefit compared with no compression.

Effects of Clinical Pathway Implementation in Management of Pediatric Inpatients with Pneumonia: A Cross-Sectional Study in Indonesia

Pneumonia is the leading cause of morbidity and mortality in children worldwide. Antibiotics are the mainstay treatment for bacterial pneumonia so their use should be clearly mentioned in the pneumonia clinical pathway (CP). This study aimed to evaluate the effectiveness of pneumonia CP in pediatrics. A cross-sectional observational study was conducted in a private hospital in Indonesia. The inclusion criteria were pediatric patients admitted with pneumonia in the period of January-December 2017 (pre-CP period) and January-December 2018 (post-CP) and receiving antibiotics. The effectiveness of CP was evaluated according to four parameters: length of stay, clinical outcomes, quality (Gyssens antibiogram) and quantity of antibiotics. A total of 121 eligible patients’ medical records were analyzed (60 before and 61 after CP implementation). Second and third generation cephalosporins (42.1%) predominated the use of antibiotics pre-CP period, whilst aminoglycosides (59.6%) constituted more than half of antibiotic use in post-CP group. More than half of the patients stayed in the hospital not more than 3 days pre-CP period vs 31.1% post-CP period. Nearly all patients had good clinical outcomes during hospitalization between both periods. The proportion of quality of antibiotics was less than 5% either before or after CP implementation. The quantity of antibiotics post-CP (408.42 defined daily dose/DDD per 100 patient days) was almost two times of pre-CP period (222.42 DDD per 100 patient days). In conclusion, implementation of CP could not achieve the targeted goals to reduce the length of hospitalization and improve the antibiotic use. No discernible difference was observed in clinical outcomes before and after CP implementation.

Medicine e-mentoring: accessibility and suitability of e-mentoring for applicants from widening participation and non-widening participation backgrounds

This paper investigates the accessibility and suitability of e-mentoring to support access to medicine for applicants from diverse backgrounds. Through qualitative analysis of the conversations between mentors (current medical students) and mentees it aims to identify the main concerns of potential medical applicants and investigate similarities and differences between mentees from widening participation (WP) and non-widening participation backgrounds. Thirty-six medicine applicants from varied backgrounds subscribed to e-mentoring during their UCAS application preparation making it possible to address the study's research questions. No discernible difference between WP and non-WP applicants was evident, which suggests the label is not indicative of prior knowledge or support needed to navigate the application process. E-mentoring was found to be a suitable platform for the delivery of outreach and both WP and non-WP applicants benefited equally. The findings from the study are discussed in the context of Health Professional Admissions and Outreach and the use of e-mentoring as a means of delivering on the WP access agenda.

881. Efficacy of Antibiotic Prophylaxis with Vancomycin in Cardiothoracic Surgery

Background Due to the high incidence of methicillin-resistant Staphylococcus aureus (MRSA) at the Detroit Medical Center, vancomycin is now routinely part of the prophylaxis regimen for cardiothoracic (CT) surgery. The study aims to compare the rate and types of surgical site infections (SSIs) when vancomycin is added to cefazolin for CT surgery compared to cefazolin alone. Methods This was a retrospective cohort study conducted at two university-affiliated hospitals. Patients who underwent CT surgery between January 2008 and August 2017 and had a readmission for SSI within 90 days of procedure were included. Patients who received cefazolin were compared to patients who received both cefazolin and vancomycin for CT surgery prophylaxis. The primary outcome was incidence of SSIs within 90 days of surgery as defined by the Centers for Disease Control and National Healthcare Safety Network. Results Out of 828 patients who underwent CT surgeries, there were 32 patients readmitted within 90 days for SSI. SSI occurred in 4.7% of patients who received cefazolin monotherapy, and 2.4% of patients who received both cefazolin and vancomycin (p=0.095). There was no discernible difference in types of SSI between groups. Pathogens were isolated in 78% of SSIs, with 75% Gram-positive and 19% Gram-negative organisms. SSIs resulted in an average 9.8 days in the hospital and 28.9 days of antibiotic therapy, and led to a total of 15 additional procedures. Conclusion Vancomycin added to cefazolin for prophylaxis in CT surgery resulted in lower incidence of SSI, however the difference was not statistically significant. Disclosures All Authors: No reported disclosures

Some Farm Animals Might Have a Sense About Impending Earthquakes

Stabled animals seem to grow fidgety in the hours before an earthquake, whereas their free-range counterparts show no discernible difference in behavior.

Differences in eggshell pigmentation pattern between Common Moorhen Gallinula chloropus and Eurasian Coot Fulica atra eggs

Facultative avian brood parasites increase their reproductive output by laying eggs in the nests of conspecifics or closely related species. The Common Moorhen Gallinula chloropus is a well-known facultative brood parasite that nests in wetlands, which are utilised also by a wide range of waterfowl, including the Eurasian Coot Fulica atra. The two species breed in similar habitats and have a similar egg pigmentation pattern; thus, the Coot can be a suitable host of brood-parasitic Moorhen. To study whether there is any discernible difference between the spotting pattern of Coot and Moorhen eggs, we compared the density of different sized spots on eggs of the two species. Our results show that Coot eggs have a significantly higher density of small speckles then Moorhen eggs, while the latter species has eggs with more conspicuous larger spots. Therefore, Coots can possibly rely on these differences in eggshell pattern to recognize and eject the brood parasitic Moorhen eggs.

Antimicrobial Footprints, Fairness, and Collective Harm

This chapter explores the question of whether or not individual agents are under a moral obligation to reduce their ‘antimicrobial footprint’. An agent’s antimicrobial footprint measures the extent to which her actions are causally linked to the use of antibiotics. As such, it is not necessarily a measure of her contribution to antimicrobial resistance. Talking about people’s antimicrobial footprint in a way we talk about our carbon footprint may be helpful for drawing attention to the global effects of individual behaviour and for highlighting that our choices can collectively make a real difference. But can we be morally obligated to make a contribution to resolving a collective action problem when our individual contributions by themselves make no discernible difference? I will focus on two lines of argument in favour of such obligations: whether a failure to reduce one’s antimicrobial footprint is unfair and whether it constitutes wrongdoing because it is harmful. I conclude by suggesting that the argument from collective harm is ultimately more successful.