Numerical Simulations of the Urban Microclimate

As global urbanization is accelerating and the majority of the world\u27s population continues to reside in cities, sustainable urban development is becoming increasingly crucial. Evaluation of the urban microclimate is a vital aspect of planning sustainable cities, as it can significantly impact on the health and comfort of urban residents. Computational Fluid Dynamics is a cost-effective and flexible tool to predict microclimate conditions, although often not utilized in the urban planning process until the final stages of a project due to complex pre-processing. The current practice of urban planning also often involves simulating different physical phenomena in separate tools, making it difficult to understand the interaction. This thesis presents the potential of the numerical immersed boundary framework IBOFLow as a tool for urban planners to evaluate the urban microclimate at the early stages of the design processes. The complex and time-consuming pre-processing of urban regions is eliminated using automatically generated Cartesian octree grid meshes where the complex geometries are represented by the immersed boundary methodology. The framework is validated for wind using wind tunnel experiments and compared to a commercially used software to show the importance of including the complex local terrain to generate realistic results. Finally, initial results of the heat simulations are covered to visualize the idea of IBOFlow as a means to simulate the urban microclimate at large, including all necessary physics

Landscape of logistics and the time present

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 152-155).Upon arrival in Memphis by air, a sign welcomes passengers to "Memphis - America's Distribution Center", a reflection of one's place in the city, and the country. Rather than a romantic reflection of the cultural heritage of the city with Elvis Presley and B.B. King, the statement places passengers not at the destination of their travels, vis a vis a "welcome to", but en route somewhere else. Memphis International Airport, identified via its aviation code "MEM", is not a place of arrival-a terminal, from "terminus", the end-but a location to be passed through-a state of being in transit or colloquially "passing through". Few passengers and goods conclude their travel here; MEM's raison d'etre is as a layover, as travelers are being distributed elsewhere as a result of the efficiency of the hub-and-spoke model of aviation. As a result, MEM is the world's busiest cargo airport. At its peak, an upwards of six flights arriving a minute carrying Apple computers, Mickey Mouse plush toys, cooking items from William-Sonoma, and the variety of other goods to and from all corners of the world destined for FedEx's so-called SuperHub. Because of the presence of such a facility, MEM has arisen as an economic capital in an improbably location within the interior of the United States replete with its own sprawling developments. MEM, as an airport city, challenges the social and cultural norms of what one considers a traditional city, as its reasons for being is the economy of moving goods and founded on the way we do business and not the way we live. This thesis proposes an urban form for MEM's surrounding city that serves as a means of regeneration of the surrounding, decaying area as well as accepts the condition of being in transit for goods and people as a primary condition of existence. In Brophy's character's words, it is an urbanism that "[perpetually remains] in the present moment, in at least semi-sempiternal transit between departure from the past and arrival in the future" and is more appropriate than the status quo within the context of MEM with regard to the transitory nature of goods, passengers and employees. The urban logic is thus a metaphor of FedEx in the transposition of technological logics, such as the flow of bodies and the interface of machine, the parcel, and the human occupant.by Anthony P. Vanky.S.M

Improving reproductive function in women with polycystic ovary syndrome with high-intensity interval training (IMPROV-IT): study protocol for a two-centre, three-armed randomised controlled trial.

INTRODUCTION: Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women of reproductive age and the leading cause of anovulatory infertility. Women with PCOS have a 15-fold higher prevalence of infertility, compared with women without PCOS, independent of body mass index (BMI). A healthy lifestyle is recommended to improve overall health and fertility in PCOS but there is limited evidence on the isolated effects of exercise, especially for reproductive outcomes. Previous findings indicate superior metabolic health benefits after vigorous compared with moderate-intensity exercise. Our primary aim is to determine the effect of high-intensity interval training (HIT) on menstrual frequency, as a proxy of reproductive function, in women with PCOS. METHODS AND ANALYSIS: The study is a two-centre, randomised, controlled trial with three parallel groups. Women (n=64) from Trondheim (Norway) and Melbourne (Australia) with PCOS according to the Rotterdam criteria will be randomly allocated (1:1:1) to high-volume HIT, low-volume HIT or a control group with no exercise after stratifying for BMI < or ≥ 27 kg/m2 and study centre. Measurements for study end points will be undertaken at baseline, after a 16 week exercise intervention and at 12 months following baseline assessments. The primary outcome measure is menstruation frequency, measured as the number of self-reported menstrual bleedings divided by the number of expected menstrual bleedings during a 12-month period. Secondary outcome measurements include markers of cardiovascular, metabolic and reproductive health, as well as quality of life and adherence to and enjoyment of exercise. ETHICS AND DISSEMINATION: The Regional Committee Medical Research Ethics, Norway, and The Australian Catholic University Human Research Ethics Committee, Australia, have approved the trial protocol. This trial will provide new insight regarding the impact of exercise on fertility in PCOS. We expect this trial to contribute to new therapeutic exercise strategies as part of clinical care for women with PCOS. TRIAL REGISTRATION NUMBER: Clinical trial gov NCT02419482

Boundary layer convective-like activity at Dome Concordia, Antarctica

The paper presents the micro-meteorological field experiment carried out at the plateau station of Dome Concordia (3300 m a.s.l.) during the Antarctic summer of 1997. The experiment dealt with the study of the trends of boundary layer features and the characteristics of the surface energy and momentum exchanges. A monostatic Doppler sodar, fast-response sensors and radiometers were used for this study. The experiment was part of a program that aims to assess the role of the continental polar regions in shaping the surface circulation over Antarctica. In spite of the markedly stable conditions found throughout the investigated period, some convective-like activity was detected during the warmer hours of the day

Metformin exposure, maternal PCOS status and fetal venous liver circulation: A randomized, placebo-controlled study

Background: Metformin is prescribed to women with polycystic ovary syndrome (PCOS) to prevent pregnancy complications. Children exposed to metformin vs. placebo in utero, have increased head circumference at birth and are more overweight and obese at 8 years of age. Also, maternal PCOS-status seems to alter the long-term cardio-metabolic health of offspring. We hypothesized that the long-term effects of metformin-exposure and/or maternal PCOS may be mediated by circulatory adaptations during fetal life. Material and methods: This is a sub-study of a larger double-blinded, placebo-controlled trial, where women with PCOS were randomized to metformin (2g/day) or placebo in pregnancy, a total of 487 women. A sub-group of participants (N = 58) took part in this sub-study and had an extended ultrasound examination at gestational week 32, including blood flow velocity and diameter measurements of the umbilical vein (UV), the ductus venosus (DV) and the portal vein (PV). Blood flow volume was calculated and adjusted for estimated fetal weight (EFW) (normalized flow). Metformin exposed fetuses were compared to placebo exposed fetuses. Fetuses of mothers with PCOS (metformin [n = 30] and placebo [n = 28]) were compared to a low-risk reference population (N = 160) by z-score statistics. Results: There was no difference in fetal liver flow between metformin vs. placebo-exposed fetuses. Fetuses of mothers with PCOS had higher EFW (0.63 [95% CI 0.44–0.83] p<0.001), lower normalized UV, DV, PV, and lower total venous liver blood flows than the reference population. Conclusion: Metformin during pregnancy did not affect fetal liver blood-flow. In our population, maternal PCOS-status was associated with reduced total venous liver blood-flow, which may explain altered growth and metabolism later in life.publishedVersio

High-intensity interval training in polycystic ovary syndrome : A two-center, three-armed randomized

Purpose Exercise training is recommended to improve cardiometabolic health and fertility in women with polycystic ovary syndrome (PCOS), yet there are few randomized controlled trials on the effects of different exercise protocols on clinical reproductive outcomes. Our aim was to determine the effect of high-intensity interval training (HIT) on menstrual frequency, as a proxy of reproductive function, in women with PCOS. Methods The IMPROV-IT study was a two-center randomized controlled trial undertaken in Norway and Australia. Women with PCOS were eligible for inclusion. After stratification for body mass index <27 or ≥27 kg·m−2 and study center, participants were randomly allocated (1:1:1) to high-volume HIT (HV-HIT), low-volume HIT (LV-HIT), or a control group. Measurements were assessed at baseline, after the 16-wk exercise intervention, and at 12-month follow-up. The primary outcome was menstrual frequency after 12 months. Secondary outcomes included markers of cardiometabolic and reproductive health, quality of life, and adherence to and enjoyment of HIT. Results We randomly allocated 64 participants to the HV-HIT (n = 20), LV-HIT (n = 21), or control group (n = 23). There were no differences in menstrual frequency at 12 months between the LV-HIT and control groups (frequency ratio, 1.02; 95% confidence interval [CI], 0.73–1.42), the HV-HIT and control groups (frequency ratio, 0.93; 95% CI, 0.67–1.29), or the LV-HIT and HV-HIT groups (frequency ratio, 1.09; 95% CI, 0.77–1.56). Menstrual frequency increased in all groups from baseline to 12 months. More participants became pregnant in the LV-HIT group (n = 5) than in the control group (n = 0, P = 0.02). Conclusions A semisupervised HIT intervention did not increase menstrual frequency in women with PCOS. Clinical Trial Registration Number:ClinicalTrials.gov (NCT02419482)

Maternal PCOS status and metformin in pregnancy: Steroid hormones in 5–10 years old children from the PregMet randomized controlled study

Objective: Polycystic ovary syndrome (PCOS) is a common endocrine disorder, with potential effects on offspring both genetically and through altered intrauterine environment. Metformin, which ameliorate hormonal disturbances in non-pregnant women with PCOS is increasingly used in pregnancy. It passes the placenta, and the evidence on potential consequences for offspring endocrine development is scarce. We explore the potential effects of maternal PCOS status and intrauterine metformin exposure on offspring steroid hormone levels. Design: This is a follow-up study of 5–10 years old children from the PregMet-study–a randomized controlled trial comparing metformin (2000 mg/day) to placebo during PCOS pregnancies. Of the 255 children invited, 117 (46%) were included. Methods: There was no intervention in this follow-up study. Outcomes were serum levels of androstenedione, testosterone, SHBG, cortisol, 17-hydroxyprogesterone, 11-deoxycortisol and calculated free testosterone converted to gender-and age adjusted z-scores from a Norwegian reference population. These were compared in i) placebo-exposed children versus children from the reference population (z-score zero) by the deviation in z-score by one-sample t-tests and ii) metformin versus placebo-exposed children by two-sample t-tests. Holm-Bonferroni adjustments were performed to account for multiple endpoints. Results: Girls of mothers with PCOS (n = 30) had higher mean z-scores of androstenedione (0.73 (95% confidence interval (CI) 0.41 to 1.06), p<0.0001), testosterone (0.76 (0.51 to 1.00), p<0.0001), and free testosterone (0.99 (0.67 to 1.32), p<0.0001) than the reference population. Metformin-exposed boys (n = 31) tended to have higher 11-deoxycortisol z-score than placebo-exposed boys (n = 24) (mean difference 0.65 (95% CI 0.14–1.17), p = 0.014). Conclusion: Maternal PCOS status was associated with elevated androgens in 5- to 10-year-old daughters, which might indicate earlier maturation and increased risk of developing PCOS. An impact of metformin in pregnancy on steroidogenesis in children born to mothers with PCOS cannot be excluded. Our findings need confirmation in studies that include participants that have entered puberty.publishedVersio

Risk of pre-eclampsia in women taking metformin: a systematic review and meta-analysis

© 2017 Diabetes UK Aims: To perform meta-analyses of studies evaluating the risk of pre-eclampsia in high-risk insulin-resistant women taking metformin prior to, or during pregnancy. Methods: A search was conducted of the Medline, EMBASE, Web of Science and Scopus databases. Both randomized controlled trials and prospective observational cohort studies of metformin treatment vs. placebo/control or insulin either prior to or during pregnancy were selected. The main outcome measure was the incidence of pre-eclampsia in each treatment group. Results: Overall, in five randomized controlled trials comparing metformin treatment (n = 611) with placebo/control (n = 609), no difference in the risk of pre-eclampsia was found [combined/pooled risk ratio (RR), 0.86 (95% CI 0.33–2.26); P = 0.76; I2 = 66%]. Meta-analysis of four cohort studies again showed no significant effect [RR, 1.21 (95% CI 0.56–2.61); P = 0.62; I2 = 30%]. A meta-analysis of eight randomized controlled trials comparing metformin (n = 838) with insulin (n = 836), however, showed a reduced risk of pre-eclampsia with metformin [RR, 0.68 (95% CI 0.48–0.95); P = 0.02; I2 = 0%]. No heterogeneity was present in the metformin vs. insulin analysis of randomized controlled trials, whereas high levels of heterogeneity were present in studies comparing metformin with placebo/control. Pre-eclampsia was a secondary outcome in most of the studies. The mean weight gain from time of enrolment to delivery was lower in the metformin group (P = 0.05, metformin vs. placebo; P = 0.004, metformin vs. insulin). Conclusions: In studies randomizing pregnant women to glucose-lowering therapy, metformin was associated with lower gestational weight gain and a lower risk of pre-eclampsia compared with insulin