In Disguise or Out of Reach: First Clues about In Situ and Accreted Stars in the Stellar Halo of the Milky Way from <i>Gaia</i> DR2

Haywood, M.,Di Matteo, P.,Lehnert, M. D.,Snaith, O.,Khoperskov, S.,Gó,mez, A. American Astronomical Society 2018 The Astrophysical journal Vol.863 No.2

Phylogeny of the Milky Way’s inner disk and bulge populations: Implications for gas accretion, (the lack of) inside-out thick disk formation, and quenching

Haywood, Misha,Di Matteo, Paola,Lehnert, Matthew,Snaith, Owain,Fragkoudi, Francesca,Khoperskov, Sergey Springer-Verlag 2018 Astronomy and astrophysics Vol.618 No.-

<P>We show that the bulge and the disk of the Milky Way (MW) at <I>R</I> ≲ 7 kpc are well described by a unique chemical evolution and a two-phase star formation history (SFH). We argue that the populations within this inner disk, not the entire disk, are the same, and that the outer Lindblad resonance (OLR) of the bar plays a key role in explaining this uniformity. In our model of a two-phase SFH, the metallicity, [<I>α</I>/Fe] and [<I>α</I>/H] distributions, and age-metallicity relation are all compatible with the observations of both the inner disk and bulge. The dip at [Fe/H] ∼ 0 dex seen in the metallicity distributions of the bulge and inner disk reflects the quenching episode in the SFH of the inner MW at age ∼8 Gyr, and the common evolution of the bulge and inner disk stars. Our results for the inner region of the MW, <I>R</I> ≲ 7 kpc, are consistent with a rapid build-up of a large fraction of its total baryonic mass within a few billion years. We show that at <I>z</I> ≤ 1.5, when the MW was starting to quench, transitioning between the end of the <I>α</I>-enhanced thick disk formation to the start of the thin disk, and yet was still gas rich, the gas accretion rate could not have been significant. The [<I>α</I>/Fe] abundance ratio before and after this quenching phase would be different, which is not observed. The decrease in the accretion rate and gas fraction at <I>z</I> ≤ 2 was necessary to stabilize the disk allowing the transition from thick to thin disks, and for beginning the secular phase of the MW’s evolution. This possibly permitted a stellar bar to develop which we hypothesize is responsible for quenching the star formation. The present analysis suggests that MW history, and in particular at the transition from the thick to the thin disk - the epoch of the quenching - must have been driven by a decrease of the star formation efficiency. We argue that the decline in the intensity of gas accretion, the formation of the bar, and the quenching of the star formation rate (SFR) at the same epoch may be causally connected thus explaining their temporal coincidence. Assuming that about 20% of the gas reservoir in which metals are diluted is molecular, we show that our model is well positioned on the Schmidt-Kennicutt relation at all times.</P>

The elderly gravidas: What are the risk?

( Haywood L. Brown ) 대한산부인과학회 2018 대한산부인과학회 학술대회 Vol.104 No.-

This presentation will focus on pregnancy in women after 40 years of age. At the conclusion of the presentation the participants will come to appreciate the association of medical and obstetric complications in pregnancy with advanced reproductive age in the 4thdecade. We will examine the question, “What is advanced maternal age in 2018? The age of 35 has traditionally been used to discuss advanced maternal age prior because of the association with chromosomal aneuploidy which increases for conceptions occurring in into the late 30’s and 40’s. However, medical and obstetrical complications are significantly more likely in women who conceive spontaneously or with in vitro methods particularly in 40’s and especially after age 45. The example, the risk for the development of hypertension/preeclampsia and diabetes are significantly greater. Of more concern, the risk for the women having a major cardiac event leading to morbidity and mortality for pregnancies after age 45 years. The risk for composite cardiac morbidity and death is 10 times greater compared to women age < 35 years.

Pregnancy complications and long term women's health

( Haywood L. Brown ) 대한산부인과학회 2018 서울심포지움 Vol.23 No.-

When the Milky Way turned off the lights: APOGEE provides evidence of star formation quenching in our Galaxy

Haywood, M.,Lehnert, M. D.,Di Matteo, P.,Snaith, O.,Schultheis, M.,Katz, D.,Gó,mez, A. Springer-Verlag 2016 Astronomy and astrophysics Vol.589 No.-

Hiding its age: the case for a younger bulge

Haywood, M.,Di Matteo, P.,Snaith, O.,Calamida, A. EDP Sciences 2016 Astronomy and astrophysics Vol.593 No.-

Alfuzosin and Its Effect on Ejaculatory Dysfunction: A Systematic Review

Yeung Haywood E. L.,Sena Stephen J.,Calopedos Ross J.,Woo Henry H. 대한남성과학회 2021 The World Journal of Men's Health Vol.39 No.2

Studies have demonstrated that alfuzosin not only improves lower urinary tract symptoms (LUTS) but also appears to preserve ejaculatory dysfunction (EjD). The objective of this study was to evaluate the impact of alfuzosin on ejaculatory function using the ‘Male Sexual Health Questionnaire (MSHQ)-EjD Short Form’ – a validated, abridged-version of the 25-item MSHQ specifically assessing EjD. A systematic search of MEDLINE, PubMed, Scopus, Embase, and grey literature was performed in January 2017 to identify relevant cohort studies. Search terms were ‘alfuzosin’, ‘benign prostatic hyperplasia’, ‘ejaculatory dysfunction’ and their synonyms without exclusions. Six cohort studies conducted between 2008 to 2015 were selected for analysis. Three of these were conducted in Korea, one in Thailand, one in China, and one in Tunisia. Overall, 1,371 patients were enrolled in these studies with a median age of 62.3 years. All studies quantified patient LUTS and ejaculatory function using the International Prostate Symptom Score (IPSS) and MSHQ-EjD Short Form, respectively. IPSS had a median decrease of 6.6 while MSHQ-EjD had a median increase of 1.9. This review highlights the very real association between sexual function and LUTS. This systematic review confirms that alfuzosin may improve ejaculatory function in addition to LUTS and should be considered in men who are sexually active or who already complain of deteriorating ejaculation.

Code Optimization Techniques to Reduce Energy Consumption of Multimedia Applications in Hybrid Memory

Thomas Haywood Dadzie,Seungpyo Cho,Hyunok Oh 대한전자공학회 2016 IEIE Transactions on Smart Processing & Computing Vol.5 No.4

This paper proposes code optimization techniques to reduce energy consumption of complex multimedia applications in a hybrid memory system with volatile dynamic random access memory (DRAM) and non-volatile spin-transfer torque magnetoresistive RAM (STT-MRAM). The proposed approach analyzes read/write operations for variables in an application. Based on the profile, variables with a high read operation are allocated to STT-MRAM, and variables with a high write operation are allocated to DRAM to reduce energy consumption. In this paper, to optimize code for real-life complicated applications, we develop a profiler, a code modifier, and compiler/link scripts. The proposed techniques are applied to a Fast Forward Motion Picture Experts Group (FFmpeg) application. The experiment reduces energy consumption by up to 22%.

Comparison of the effects of simulated patient clinical skill training and student roleplay on objective structured clinical examination performance among medical students in Australia

Silas Taylor,Matthew Haywood,Boaz Shulruf 한국보건의료인국가시험원 2019 보건의료교육평가 Vol.16 No.-

PurposeOptimal methods for communication skills training (CST) are an active research area, but the effects of CST on communication performance in objective structured clinical examinations (OSCEs) has not been closely studied. Student roleplay (RP) for CST is common, although volunteer simulated patient (SP) CST is cost-effective and provides authentic interactions. We assessed whether our volunteer SP CST program improved OSCE performance compared to our previous RP strategy. MethodsWe performed a retrospective, quasi-experimental study of 2 second-year medical student cohorts’ OSCE data in Australia. The 2014 cohort received RP-only CST (N=182) while the 2016 cohort received SP-only CST (N=148). The t-test and analysis of variance were used to compare the total scores in 3 assessment domains: generic communication, clinical communication, and physical examination/procedural skills. ResultsThe baseline characteristics of groups (scores on the Australian Tertiary Admission Rank, Undergraduate Medicine and Health Sciences Admission Test, and medicine program interviews) showed no significant differences between groups. For each domain, the SP-only CST group demonstrated superior OSCE outcomes, and the difference between cohorts was significant (P<0.01). The superiority of volunteer SP CST over student RP CST in terms of OSCE performance outcomes was found for generic communication, clinical communication, and physical examination/procedural skills. ConclusionThe better performance of the SP cohort in physical examination/procedural skills might be explained by the requirement for patient compliance and cooperation, facilitated by good generic communication skills. We recommend a volunteer SP program as an effective and efficient way to improve CST among junior medical students.

Association between Hemoglobin A1c and Stroke Risk in Patients with Type 2 Diabetes

Yun Shen,Lizheng Shi,Elizabeth Nauman,Peter Katzmarzyk,Eboni Price-Haywood,Alessandra Bazzano,Somesh Nigam,Gang Hu 대한뇌졸중학회 2020 Journal of stroke Vol.22 No.1

Background and Purpose The association between hemoglobin A1c (HbA1c) and stroke risk along with its subtypes is rarely reported. We aimed to investigate the association between HbA1c and the risk of incident stroke in patients with type 2 diabetes based on real world data from three healthcare systems. Methods We performed a retrospective cohort study of 27,113 African Americans and 40,431 whites with type 2 diabetes. Demographic, anthropometric, laboratory, and medication information were abstracted from the National Patient-Centered Clinical Research Network common data model. Incident stroke events including both ischemic and hemorrhagic stroke were defined. Results During a mean follow-up period of 3.79±1.68 years, 7,735 patients developed stroke (6,862 ischemic and 873 hemorrhagic). Multivariable-adjusted hazard ratios across levels of HbA1c at baseline (<6.0%, 6.0% to 6.9% [reference group], 7.0% to 7.9%, 8.0% to 8.9%, 9.0% to 9.9%, and ≥10%) were 1.07, 1.00, 1.13, 1.23, 1.27, and 1.37 (Ptrend <0.001) for total stroke, 1.02, 1.00, 1.13, 1.20, 1.24, and 1.35 (Ptrend <0.001) for ischemic stroke, and 1.40, 1.00, 1.14, 1.47, 1.47, and 1.51 (Ptrend=0.002) for hemorrhagic stroke. When we used an updated mean value of HbA1c, the U-shaped association of HbA1c with stroke risk did not change. This U-shaped association was consistent among patients of different subgroups. The U-shaped association was more pronounced among patients taking antidiabetic, lipid-lowering, and antihypertensive medications compared with those without these medications. Conclusions These data suggest that diabetes management may have to be individualized according to the guideline recommendations rather than intensively attempting to lower HbA1c.