Understanding fire growth for performance based design of bamboo structures

This paper analyses the different parameters governing fire growth and presents the results obtained for laminated bamboo samples produced from the species Phyllostachys pubescens “Moso”. Parameters such as critical heat flux, temperature for ignition, thermal inertia, mass loss rate and heat release rates are studied herein. Last, the ignition parameters of laminated bamboo are contrasted against the available information on bamboo and commonly used timber products. Results show that overall, laminated bamboo show higher critical heat flux for ignition, ignition temperature, and thermal inertia when compared to timber species

High resolution HLA-A, -B, -C and -DRB1 allele and haplotype frequencies in the Costa Rica Central Valley population

The Costa Rica Central Valley population (CCVP) is the major population in this country, accounting for over 60% of the Costa Rican inhabitants concentrated since colonial times in a 2,500 km2 intermontane region. Interesting historic, demographic and genetic characteristics of this hybrid population have attracted researchers interested in testing genetic associations for various diseases. However, no study describing Human Leukocyte Antigen (HLA) frequencies by molecular methods had been performed. We have recently described low resolution HLA allele group and haplotype frequencies in a sample of this population. In this report, we extend our study to high resolution by sequence-based typing of exons 2, 3 and 4 for class I, and exon 2 for HLA-DRB1. DNA was extracted from blood or saliva samples from a cohort of 205 non-related healthy donors recruited as part of the University of Costa Rica’s Centre for Research in Hematology and Related Disorders (CIHATA) DNA bank. All participants were born in the CCVP and gave informed consent. A total of 37 HLA-A, 61 HLA-B, 24 HLA-C and 38 HLA-DRB1 alleles were seen in this sample. The five most frequent alleles for these genes are HLA-A*02:01:01, HLA-A*24:02:01, HLA-A*03:01:01, HLA-A*01:01:01, HLA-A*68:01:02, HLA-B*07:02:01, HLA-B*40:02:01, HLA-B*35:01:01, HLA-B*44:02:01, HLA-B*14:02:01, HLA-C*04:01:01, HLA-C*07:02:01, HLA-C*03:05, HLA-C*06:02:01, HLA-C*07:01:01, HLA-DRB1*13:01:01G, HLA-DRB1*04:07:01G, HLA-DRB1*15:01:01G, HLA-DRB1*03:01:01G, and HLA-DRB1*07:01:01G. Preliminary haplotype estimation results show, as a proxy for admixture proportions, that 68% of the extended haplotypes are Caucasian, while 23% are Amerindian in origin and 9% are clearly Sub-Saharan African. Principal coordinates analysis based on HLA-A and –B allele group frequencies reveals that this population clusters among other admixed groups with strong Caucasian component that lie closely to Iberian populations

Exploring Vitamin B1 Cycling and Its Connections to the Microbial Community in the North Atlantic Ocean

Vitamin B1 (thiamin) is an essential coenzyme for all cells. Recent findings from experimental cell biology and genome surveys have shown that thiamin cycling by plankton is far more complex than was previously understood. Many plankton cells cannot produce thiamin (are auxotrophic) and obligately require an exogenous source of thiamin or one or more of 5 different thiamin-related compounds (TRCs). Despite this emerging evidence for the evolution among plankton of complex interactions related to thiamin, the influence of TRCs on plankton community structure and productivity are not understood. We report measurements of three dissolved TRCs 4-amino-5-aminomethyl-2-methylpyrimidine (AmMP), 5-(2-hydroxyethyl)-4-methyl-1,3-thiazole-2-carboxylic acid (cHET), and 4-methyl-5-thiazoleethanol (HET) that have never before been assayed in seawater. Here we characterize them alongside other TRCs that were measured previously [thiamin and 4-amino-5-hydroxymethyl-2-methylpyrimidine (HMP)], in depth profiles from a latitudinal transect in the north Atlantic in March 2018. TRC concentrations ranged from femptomolar to picomolar. Surface depletion relative to a maximum near the bottom of the euphotic zone and low concentrations at deeper depths were consistent features. Our observations suggest that when bacterial abundance and production are low, TRC concentrations approach a steady state where TRC production and consumption terms are balanced. Standing stocks of TRCs also appear to be positively correlated with bacterial production. However, near the period of peak biomass in the accumulation phase of a bloom we observed an inverse relationship between TRCs and bacterial production, coincident with an increased abundance of Flavobacteria that comparative genomics indicates could be vitamin B1 auxotrophs. While these observations suggest that the dissolved pool of TRCs is often at steady state, with TRC production and consumption balanced, our data suggests that bloom induced shifts in microbial community structure and activity may cause a decoupling between TRC production and consumption, leading to increased abundances of some populations of bacteria that are putatively vitamin B1 auxotrophs

Structural insights into the role of domain flexibility in human DNA ligase IV.

Knowledge of the architecture of DNA ligase IV (LigIV) and interactions with XRCC4 and XLF-Cernunnos is necessary for understanding its role in the ligation of double-strand breaks during nonhomologous end joining. Here we report the structure of a subdomain of the nucleotidyltrasferase domain of human LigIV and provide insights into the residues associated with LIG4 syndrome. We use this structural information together with the known structures of the BRCT/XRCC4 complex and those of LigIV orthologs to interpret small-angle X-ray scattering of LigIV in complex with XRCC4 and size exclusion chromatography of LigIV, XRCC4, and XLF-Cernunnos. Our results suggest that the flexibility of the catalytic region is limited in a manner that affects the formation of the LigIV/XRCC4/XLF-Cernunnos complex

Nuclear WRAP53 promotes neuronal survival and functional recovery after stroke

Failure of neurons to efficiently repair DNA double-strand breaks (DSBs) contributes to cerebral damage after stroke. However, the molecular machinery that regulates DNA repair in this neurological disorder is unknown. Here, we found that DSBs in oxygen/glucose-deprived (OGD) neurons spatiotemporally correlated with the up-regulation of WRAP53 (WD40-encoding p53-antisense RNA), which translocated to the nucleus to activate the DSB repair response. Mechanistically, OGD triggered a burst in reactive oxygen species that induced both DSBs and translocation of WRAP53 to the nucleus to promote DNA repair, a pathway that was confirmed in an in vivo mouse model of stroke. Noticeably, nuclear translocation of WRAP53 occurred faster in OGD neurons expressing the Wrap53 human nonsynonymous single-nucleotide polymorphism (SNP) rs2287499 (c.202C>G). Patients carrying this SNP showed less infarct volume and better functional outcome after stroke. These results indicate that WRAP53 fosters DNA repair and neuronal survival to promote functional recovery after stroke

Demonstrable Evidence of Beneficial Physical Outcomes from University Physical Education Activity Courses

Introduction: Engagement in physical activity (PA) is often dramatically reduced during the transition from high school into college. There appears to be more stability in PA patterns during the transition from college into post-graduate life. Consequently, researchers have highlighted the years in higher education as pivotal for shaping lasting PA habits. Sadly, there is a widespread lack of evidence regarding the outcomes from physical education activity courses (PEAC) offered on campuses of higher education. Thus, their overall value lacks validation. The purpose of this work was to offer evidence of outcomes from engagement in a single, semester-long university PEAC class. Methods: Students were recruited from a variety of classes. There were no directions provided to the instructors of the courses. For grouping, classes were categorized as aerobic- (aerobics, jogging, and walking) or sport-activity (badminton, pickle ball, self-defense, strength training, and ultimate frisbee). Students in the aerobic-activity arm were randomized to aerobic testing where they underwent a submaximal treadmill protocol and grip strength (GS) testing or body composition testing (air displacement plethysmography) and GS. Those in the sport-activity arm underwent vertical jump and GS testing. Students reported to the human performance lab in the first two and final two weeks of the semester. Paired t-tests were conducted to identify differences in pre-post outcomes. Values were carried forward, not dropped, when a subject failed to return at post-test. Results: A total of 46 students (age = 21.7 ± 4.1) were randomized into the aerobic (n=25; m/f = 11/14) or body composition arms (n=21; m/f = 7/14). Additionally, 45 students (age = 20.8 ± 3.2; m/f = 23/22) from sport-activity classes were enrolled. Participation in aerobic-activity classes resulted in improvements in estimated maximal aerobic ability (p = 0.030; 42.9 ± 9.9 vs. 44.6 ± 10.1). Participation also resulted in increases in GS for those allocated to both the aerobic (p = 0.010; 56.4 ± 21.5 vs. 60.3 ± 22.3) and body composition (p = 0.022; 54.1 ± 22.1 vs. 58.1 ± 24.6) arms. Participation did not result in changes in body composition (p = 0.817; 24.7 ± 8.5 vs. 24.6 ± 7.4) despite a near-significant increase in weight (p = 0.057; 152.7 ± 38.5 vs. 154.5 ± 37.7). Participation in sport-activity classes resulted in an improvement in vertical jump (p = 0.007; 18.2 ± 6.1 vs. 18.9 ± 6.0) and GS (p = 0.002; 65.3 ± 25.6 vs. 70.0 ± 27.8). Discussion: An important first step in rebutting challenges about the credibility and worthiness of PEAC offerings is evidencing beneficial outcomes. These results represent simple, but important, markers of change. Additional demonstrable evidence is needed to ascertain elements such as what outcomes are achievable, what classes are most effective classes, and what components from class support lasting change