Drilling Induced Fatigue Damage in Ti-6Al-4V

The objective of this work is to develop an understanding of the relationship between hole drilling processes and the fatigue performance of the resulting part in Ti-6Al-4V. This problem is significant, as on the order of one-hundred thousand to a million holes are created in a typical large aircraft, and the limiting performance criterion is usually the fatigue lifetime. The path between the drilling process parameters and the fatigue performance has two main steps: characterization of the thermo-mechanical drill process and assessment of the relationship between the hole integrity left by the drill process and the fatigue performance. Development has been limited by the robustness of previously available thermal characterization systems, poor correlation between drill processes and physical observations of metallic effects, and limited success identifying the key hole integrity characteristics. This work develops robust novel thermal methods which enable integration into current drill process development techniques. The key integrity drivers in the hole wall are identified, characterized, and a system to assess is presented. The thermal and hole integrity trends are presented as guidance for drill process development providing significant opportunities to optimize processes. Thus, this work advances knowledge of the process to fatigue lifetime relationship by correlating the thermo-mechanical drill process to fatigue life in Ti-6Al-4V

Mating Type, Vitamin E And Morphogenesis In Ustilago Violacea And Other Smut Fungi

The anther smut fungus, Ustilago violacea, grows either saprophytically (yeastlike cells) or as a parasite of the Caryophyllaceae (mycelial cells). Factors affecting two types of development controlled by the mating type gene, sporulation and myceliation, were examined.;Sporulation. Freshly isolated diploid cells, heterozygous for the mating type alleles, a(,1) and a(,2), develop into sexual phase precursor cells (SPP) on complete medium at temperatures below 20(DEGREES)C. The a(,1)/a(,2) diploid produces at least four different cell types, termed opaques, spontaneously at high frequencies (\u3e 3 x 10(\u27-3)). These types are: (1) neutral strains (op-N) which do not mate and still initiate sporulation but under altered conditions. (2) Strains which mate as a(,1) types (op-a(,1)) and (3) cells which mate as a(,2) types (op-a(,2)). (4) Constitutively self mating (op-C) strains. Types 2 to 4 have lost the ability to develop into SPP cells. These four strains were shown to remain diploid and to be altered only at the mating type locus or chromosome. Genetic analyses of tetraploid (op-a(,1) x op-a(,2)) and triploid (op-a(,1) x haploid a(,2)) crosses indicated that the mating opaques probably arise after mitotic crossing-over yielding a(,1)/a(,1) (op-a(,1)) and a(,2)/a(,2) (op-a(,2)) types. Experiments showing similar increases in opaque frequency and mitotic recombination near marker alleles following UV irradiation support this conclusion.;Myceliation. Aqueous extracts from plants that host Ustilago species were found to induce the mycelial stage of U. violacea and some other smut species in cells that were potentially pathogenic i.e. expressed both mating type alleles. Aqueous extracts from most non-host species were inactive. However, efficient extraction of all tested plant species with organic solvents indicated that the stimulatory compound was universal in distribution. (alpha)-Tocopherol was identified as the major active compound in plant extracts. All tested host species contained amounts of tocopherol above the threshold level (5 x 10(\u27-8) M) while non-hosts had either (1) above threshold levels of tocopherol; (2) above threshold levels of tocopherol plus toxins or inhibitors; or (3) sub-threshold levels of tocopherol. These results suggest that the availability of tocopherol may form one basis for the restriction of the host range of Ustilago species

Individual differences in maternal behaviour in the grey seal (Halichoerus grypus) and the impact of disturbance at Donna Nook.

The grey seal (Halichoerus grypus) is a semi-aquatic pinniped and a member of the family phocidae. On shore breeding colonies form around the UK during the autumn, on which female grey seals rear a single pup for up to 3 weeks. This study aimed to identify the presence, if any, of consistent individual differences (CIDs) in maternal behaviour of grey seals on the breeding colony at Donna Nook. Data collection was non-intrusive, using in-field focal videos, pup-check counts and proximity maps. In agreement with previous research on North Rona, results from the current study show CIDs in pup-check behaviour at Donna Nook. CIDs were present in time mothers spent interacting with their pup and time spent nursing. These findings provide preliminary evidence for the existence of grey seal personalities, or more specifically, mothering styles. There was no evidence that pup gender influenced maternal behavioural investment. There was evidence for habituation to human disturbance; females exposed to the public showed a lower duration of alert behaviour and no difference in duration of pup interaction compared to the restricted site. This habituation was no longer evident following exposure to sudden disturbance (in this case, an unforeseen tidal storm surge). A colony wide increase in pup-check duration and decrease in colony density was observed in the weeks following the storm surge. The results of this study highlight the scope for future research into the stability of these CIDs over numerous breeding seasons and effects of these differences on pup development. Perhaps most importantly, this study provides the first photographic identification catalogue for females at Donna Nook, an excellent basis for future research

Exploring Socio-Cultural Perspectives on Diversity

This Grants Collection uses the grant-supported open textbook OpenEDUC from the University of Georgia: http://oer.galileo.usg.edu/education-textbooks/4 This Grants Collection for Critical and Contemporary Issues in Education was created under a Round Two ALG Textbook Transformation Grant. Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process. Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/education-collections/1000/thumbnail.jp

Hydrodynamic Flow Fluctuations in √sNN = 5.02 TeV PbPb Collisions

The collective, anisotropic expansion of the medium created in ultrarelativistic heavy-ion collisions, known as flow, is characterized through a Fourier expansion of the final-state azimuthal particle density. In the Fourier expansion, flow harmonic coefficients $v_n$ correspond to shape components in the final-state particle density, which are a consequence of similar spatial anisotropies in the initial-state transverse energy density of a collision. Flow harmonic fluctuations are studied for PbPb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV using the CMS detector at the CERN LHC. Flow harmonic probability distributions $p(v_n)$ are obtained using particles with $0.3 < p_{\rm T} < 3.0$ GeV/$c$ and $\lvert \eta \rvert < 1.0$ by removing finite-multiplicity resolution effects from the observed azimuthal particle density through an unfolding procedure. Cumulant elliptic flow harmonics ($n=2$) are determined from the moments of the unfolded $p(v_2)$ distributions and used to construct observables in $5\%$ wide centrality bins up to $60\%$ that relate to the initial-state spatial anisotropy. Hydrodynamic models predict that fluctuations in the initial-state transverse energy density will lead to a non-Gaussian component in the elliptic flow probability distributions that manifests as a negative skewness. A statistically significant negative skewness is observed for all centrality bins as evidenced by a splitting between the higher-order cumulant elliptic flow harmonics. The unfolded $p(v_2)$ distributions are transformed assuming a linear relationship between the initial-state spatial anisotropy and final-state flow and are fitted with elliptic power law and Bessel Gaussian parametrizations to infer information on the nature of initial-state fluctuations. The elliptic power law parametrization is found to provide a more accurate description of the fluctuations than the Bessel-Gaussian parametrization. In addition, the event-shape engineering technique, where events are further divided into classes based on an observed ellipticity, is used to study fluctuation-driven differences in the initial-state spatial anisotropy for a given collision centrality that would otherwise be destroyed by event-averaging techniques. Correlations between the first and second moments of $p(v_n)$ distributions and event ellipticity are measured for harmonic orders $n=2-4$ by coupling event-shape engineering to the unfolding technique

Synthesis of unsaturated polyester resins from various bio-derived platform molecules

Utilisation of bio-derived platform molecules in polymer synthesis has advantages which are, broadly, twofold; to digress from crude oil dependence of the polymer industry and secondly to reduce the environmental impact of the polymer synthesis through the inherent functionality of the bio-derived platform molecules. Bulk polymerisation of bio-derived unsaturated di-acids has been employed to produce unsaturated polyester (UPEs) which have been analysed by GPC, TGA, DSC and NMR spectroscopy, advancing on the analysis previously reported. UPEs from the diesters of itaconic, succinic, and fumaric acids were successfully synthesised with various diols and polyols to afford resins of MN 480-477,000 and Tg of -30.1 to -16.6 °C with solubilities differing based on starting monomers. This range of properties allows for many applications and importantly due to the surviving Michael acceptor moieties, solubility and cross-linking can be specifically tailored, post polymerisation, to the desired function. An improved synthesis of itaconate and succinate co-polymers, via the initial formation of an itaconate bis-diol, is also demonstrated for the first time, resulting in significantly improved itaconate incorporation

Introductory Physical Education Courses (UGA)

This Grants Collection for multiple introductory Physical Education courses was created under a Round Eleven ALG Textbook Transformation Grant. Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process. Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/health-collections/1008/thumbnail.jp

Global injury morbidity and mortality from 1990 to 2017 : results from the global burden of disease study 2017

Background Past research in population health trends has shown that injuries form a substantial burden of population health loss. Regular updates to injury burden assessments are critical. We report Global Burden of Disease (GBD) 2017 Study estimates on morbidity and mortality for all injuries. methods We reviewed results for injuries from the GBD 2017 study. GBD 2017 measured injury-specific mortality and years of life lost (YLLs) using the Cause of Death Ensemble model. To measure non-fatal injuries, GBD 2017 modelled injury-specific incidence and converted this to prevalence and years lived with disability (YLDs). YLLs and YLDs were summed to calculate disability-adjusted life years (DALYs). Findings In 1990, there were 4 260 493 (4 085 700 to 4 396 138) injury deaths, which increased to 4 484 722 (4 332 010 to 4 585 554) deaths in 2017, while age-standardised mortality decreased from 1079 (1073 to 1086) to 738 (730 to 745) per 100 000. In 1990, there were 354 064 302 (95% uncertainty interval: 338 174 876 to 371 610 802) new cases of injury globally, which increased to 520 710 288 (493 430 247 to 547 988 635) new cases in 2017. During this time, age-standardised incidence decreased non-significantly from 6824 (6534 to 7147) to 6763 (6412 to 7118) per 100 000. Between 1990 and 2017, age-standardised DALYs decreased from 4947 (4655 to 5233) per 100 000 to 3267 (3058 to 3505). Interpretation Injuries are an important cause of health loss globally, though mortality has declined between 1990 and 2017. Future research in injury burden should focus on prevention in high-burden populations, improving data collection and ensuring access to medical care. © Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY. Published by BMJ. ***Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Muhammad Rahman” is provided in this record**

Estimating global injuries morbidity and mortality : methods and data used in the global burden of disease 2017 study

Background: While there is a long history of measuring death and disability from injuries, modern research methods must account for the wide spectrum of disability that can occur in an injury, and must provide estimates with sufficient demographic, geographical and temporal detail to be useful for policy makers. The Global Burden of Disease (GBD) 2017 study used methods to provide highly detailed estimates of global injury burden that meet these criteria. Methods: In this study, we report and discuss the methods used in GBD 2017 for injury morbidity and mortality burden estimation. In summary, these methods included estimating cause-specific mortality for every cause of injury, and then estimating incidence for every cause of injury. Non-fatal disability for each cause is then calculated based on the probabilities of suffering from different types of bodily injury experienced. Results: GBD 2017 produced morbidity and mortality estimates for 38 causes of injury. Estimates were produced in terms of incidence, prevalence, years lived with disability, cause-specific mortality, years of life lost and disability-adjusted life-years for a 28-year period for 22 age groups, 195 countries and both sexes. Conclusions: GBD 2017 demonstrated a complex and sophisticated series of analytical steps using the largest known database of morbidity and mortality data on injuries. GBD 2017 results should be used to help inform injury prevention policy making and resource allocation. We also identify important avenues for improving injury burden estimation in the future. © Author(s) (or their employer(s)) 2020. Re-use permitted under CC B Y. Published by BMJ. ***Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Muhammad Rahman” is provided in this record**