A forensic analysis of a fatal fire in an indoor shooting range using coupled fire and evacuation modelling tools

In this paper, coupled fire and evacuation computer simulations are used to numerically reconstruct a fatal fire that occurred in an indoor shooting range in Pusan, Korea in 2009. Of the 16 building occupants, 15 were killed and only one survived with serious injuries. The analysis demonstrates that these modelling techniques can accurately reproduce the outcome of this fire. The numerical approach is then used to forensically analyse the incident to determine what factors significantly contributed to the high loss of life. In particular, the occupant response times are analysed as is the impact of the flame spread rate on the polyurethane foam cladded walls of the shooting range. The results suggest that it is unlikely that anyone could have survived if response times were greater than 5 seconds. Furthermore, the analysis suggests that fatalities could not have been completely avoided even if the occupants had zero response time. In addition, it is demonstrated that gunpowder residue on the polyurethane foam walls is the critical factor in producing the high loss of life in this incident. The average number of fatalities could be reduced from an average of 14.9 in the reconstruction case with gunpowder residue on the polyurethane foam walls to an average of 0.1 if the walls are completely free of gunpowder residue. However, to completely eliminate fire related casualties, it is necessary to use a polyurethane foam wall cladding material with low flame spread rates together with an effective gunpowder cleaning system

Structural Insights into Rational Design of Single-Domain Antibody-Based Antitoxins against Botulinum Neurotoxins.

Botulinum neurotoxin (BoNT) is one of the most acutely lethal toxins known to humans, and effective treatment for BoNT intoxication is urgently needed. Single-domain antibodies (VHH) have been examined as a countermeasure for BoNT because of their high stability and ease of production. Here, we investigate the structures and the neutralization mechanisms for six unique VHHs targeting BoNT/A1 or BoNT/B1. These studies reveal diverse neutralizing mechanisms by which VHHs prevent host receptor binding or block transmembrane delivery of the BoNT protease domain. Guided by this knowledge, we design heterodimeric VHHs by connecting two neutralizing VHHs via a flexible spacer so they can bind simultaneously to the toxin. These bifunctional VHHs display much greater potency in a mouse co-intoxication model than similar heterodimers unable to bind simultaneously. Taken together, our studies offer insight into antibody neutralization of BoNTs and advance our ability to design multivalent anti-pathogen VHHs with improved therapeutic properties

Distributed Bragg reflectors and devices incorporating same

Distributed Bragg Reflectors of high efficacy based on alternating layers of large difference in refractive index are fabricated by epitaxial growth followed by etchant removal and back-filling to produce a structure in which alternation is between layers of retained epitaxially grown material and layers of back-filled material. Such reflectors may serve simply as mirrors or may be incorporated in a variety of devices including lasers, LEDs, detectors, optical switches in which the DBRs serve e.g. for cavitation.Published versio

The Effectiveness of a Pro-Abstinence Sex Education Curriculum in Singapore

In this study, we investigate the impact of the pro-abstinence Sex Education curriculum on youths in Singapore, by examining if there is a relationship between pro-abstinence Sex Education and the rates of Sexually Transmitted diseases (STD)/Sexually Transmitted Infections (STI). As the rates of STD/STI transmission have been on the rise, it is crucial that the system be re-evaluated to include a curriculum that educates on protection and contraception. To study this relationship, we compiled secondary data over a course of 20 to 30 years from the Ministry of Health (MOH), as well as past studies of the impact of pro-abstinence Sex Education on youths aged between 16 to 25. Despite no research about the effectiveness of Singapore’s sex education curriculum which was introduced in 2000, with multiple resources and research studies that were conducted in the United States, a comparison between the sex education curriculum in Singapore and reevaluated curriculums overseas can be made to draw a conclusion. Through regression analysis done on two different sets of data, we concluded that there was little to no difference in having a pro-abstinence Sex Education in decreasing the rate of both STI and STD

Kidney transplantation in a patient with absent right common iliac artery and congenital renal abnormalities

AbstractIntroductionCongenital atresia of the common and external iliac arteries is a rare vascular anomaly that may be associated with congenital renal or genitourinary malformations. In ESRD patients, its presence may pose potential problems during renal transplantation.Case presentationWe report a rare case of kidney transplantation in a patient with VACTERL syndrome who was found to have absent right common and external iliac arteries during pre-operative imaging. Vascular supply to the right lower limb is derived from an anomalous branch from the left internal iliac artery which takes on a convoluted course across the pelvis. Kidney transplantation was performed successfully with implantation performed on the left side.DiscussionIsolated cases of congenital iliac artery atresia have been described in association with urological abnormalities but no clear association has yet been established. However, we feel that it may be useful to perform routine angiographic evaluation for ESRD patients with congenital genitourinary abnormalities being planned for kidney transplantation. While most cases of congenital iliac artery anomalies are symptomatic with claudication, some remain asymptomatic with normal physical examination findings. There is some evidence in literature suggesting the usefulness of routine pre-operative CT in a selective group of patients.ConclusionKidney transplantation in such cases is safe and we recommend routine pre-operative imaging of patients known to have congenital genitourniary abnormalities. The kidney should be implanted heterotopically to the contralateral side of the vascular anomaly and care must be taken to preserve vascular supply to the lower limbs

A targeted gene panel that covers coding, non-coding and short tandem repeat regions improves the diagnosis of patients with neurodegenerative diseases

Genetic testing for neurodegenerative diseases (NDs) is highly challenging because of genetic heterogeneity and overlapping manifestations. Targeted-gene panels (TGPs), coupled with next-generation sequencing (NGS), can facilitate the profiling of a large repertoire of ND-related genes. Due to the technical limitations inherent in NGS and TGPs, short tandem repeat (STR) variations are often ignored. However, STR expansions are known to cause such NDs as Huntington\u27s disease and spinocerebellar ataxias type 3 (SCA3). Here, we studied the clinical utility of a custom-made TGP that targets 199 NDs and 311 ND-associated genes on 118 undiagnosed patients. At least one known or likely pathogenic variation was found in 54 patients; 27 patients demonstrated clinical profiles that matched the variants; and 16 patients whose original diagnosis were refined. A high concordance of variant calling were observed when comparing the results from TGP and whole-exome sequencing of four patients. Our in-house STR detection algorithm has reached a specificity of 0.88 and a sensitivity of 0.82 in our SCA3 cohort. This study also uncovered a trove of novel and recurrent variants that may enrich the repertoire of ND-related genetic markers. We propose that a combined comprehensive TGPs-bioinformatics pipeline can improve the clinical diagnosis of NDs

Entropy of the FRW cosmology based on the brick wall method

The brick wall method in calculations of the entropy of black holes can be applied to the FRW cosmology in order to study the statistical entropy. An appropriate cutoff satisfying the covariant entropy bound can be chosen so that the entropy has a definite bound. Among the entropy for each of cosmological eras, the vacuum energy-dominated era turns out to give the maximal entropy which is in fact compatible with assumptions from the brick wall method.Comment: 10 pages, 2 figure

An adaptive quantum approximate optimization algorithm for solving combinatorial problems on a quantum computer

The quantum approximate optimization algorithm (QAOA) is a hybrid variational quantum-classical algorithm that solves combinatorial optimization problems. While there is evidence suggesting that the fixed form of the original QAOA ansatz is not optimal, there is no systematic approach for finding better ans\"atze. We address this problem by developing an iterative version of QAOA that is problem-tailored, and which can also be adapted to specific hardware constraints. We simulate the algorithm on a class of Max-Cut graph problems and show that it converges much faster than the original QAOA, while simultaneously reducing the required number of CNOT gates and optimization parameters. We provide evidence that this speedup is connected to the concept of shortcuts to adiabaticity.Comment: 5 pages, 3 figure