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Early in the COVID-19 pandemic, the World Health Organization stressed the importance of daily clinical assessments of infected patients, yet current approaches frequently consider cross-sectional timepoints, cumulative summary measures, or time-to-event analyses. Statistical methods are available that make use of the rich information content of longitudinal assessments. We demonstrate the use of a multistate transition model to assess the dynamic nature of COVID-19-associated critical illness using daily evaluations of COVID-19 patients from 9 academic hospitals. We describe the accessibility and utility of methods that consider the clinical trajectory of critically ill COVID-19 patients.
The initial classic Fontan utilising a direct right atrial appendage to pulmonary artery anastomosis led to numerous complications. Adults with such complications may benefit from conversion to a total cavo-pulmonary connection, the current standard palliation for children with univentricular hearts.
A single institution, retrospective chart review was conducted for all Fontan conversion procedures performed from July, 1999 through January, 2017. Variables analysed included age, sex, reason for Fontan conversion, age at Fontan conversion, and early mortality or heart transplant within 1 year after Fontan conversion.
A total of 41 Fontan conversion patients were identified. Average age at Fontan conversion was 24.5 ± 9.2 years. Dominant left ventricular physiology was present in 37/41 (90.2%) patients. Right-sided heart failure occurred in 39/41 (95.1%) patients and right atrial dilation was present in 33/41 (80.5%) patients. The most common causes for Fontan conversion included atrial arrhythmia in 37/41 (90.2%), NYHA class II HF or greater in 31/41 (75.6%), ventricular dysfunction in 23/41 (56.1%), and cirrhosis or fibrosis in 7/41 (17.1%) patients. Median post-surgical follow-up was 6.2 ± 4.9 years. Survival rates at 30 days, 1 year, and greater than 1-year post-Fontan conversion were 95.1, 92.7, and 87.8%, respectively. Two patients underwent heart transplant: the first within 1 year of Fontan conversion for heart failure and the second at 5.3 years for liver failure.
Fontan conversion should be considered early when atrial arrhythmias become common rather than waiting for severe heart failure to ensue, and Fontan conversion can be accomplished with an acceptable risk profile.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
We explore the determinants of equity price risk of nonfinancial corporations. Operating and asset characteristics are by far the most important determinants of risk. For the median firm, financial risk accounts for only 15% of observed stock price volatility. Furthermore, financial risk has declined over the last 3 decades, indicating that any upward trend in equity volatility was driven entirely by economic risk factors. This explains why financial distress (as opposed to economic distress) was surprisingly uncommon in the nonfinancial sector during the 2007–2009 crisis even as measures of equity volatility reached unprecedented highs.
To determine what factors are associated with parental motivation to change body weight in overweight children.
Dunedin, New Zealand.
Two hundred and seventy-one children aged 4–8 years, recruited in primary and secondary care, were identified as overweight (BMI≥85th percentile) after screening. Parents completed questionnaires on demographics; motivation to improve diet, physical activity and weight; perception and concern about weight; parenting; and social desirability, prior to being informed that their child was overweight. Additional measures of physical activity (accelerometry), dietary intake and child behaviour (questionnaire) were obtained after feedback.
Although all children were overweight, only 42 % of parents perceived their child to be so, with 36 % indicating any concern. Very few parents (n 25, 8 %) were actively trying to change the child’s weight. Greater motivation to change weight was observed for girls compared with boys (P=0·001), despite no sex difference in BMI Z-score (P=0·374). Motivation was not associated with most demographic variables, social desirability, dietary intake, parenting or child behaviour. Increased motivation to change the child’s weight was observed for heavier children (P<0·001), those who were less physically active (P=0·002) and more sedentary (P<0·001), and in parents who were more concerned about their child’s weight (P<0·001) or who used greater food restriction (P<0·001).
Low levels of parental motivation to change overweight in young children highlight the urgent need to determine how best to improve motivation to initiate change.
Two fundamental processes associated with shock compression of energetic materials (EM) are initiation and ignition. Initiation occurs just behind a shock front and ignition occurs anywhere from a few nanoseconds to hundreds of nanoseconds later. Experiments are described that probe the fundamental mechanisms of these processes on relevant length and time scales: picosecond vibrational spectroscopy of nanometer thick layers of energetic materials (EM) with laser-driven shock waves, and nanosecond emission spectroscopy of micrometer thick layers of EM using laser-driven flyer plates.
In most practices, sonohysterography is immediately preceded by high-frequency transvaginal sonography (TVS). Exact menstrual dating and latex allergy are documented first, and a negative pregnancy test is obtained, along with a signed informed consent, when appropriate. The purpose of the baseline ultrasound is to confirm all pelvic findings prior to the fluid enhancement study. Although sonohysterography provides an indirect look inside the uterus, its ability to accurately diagnose intracavitary filling defects, such as myomas and polyps and adhesions and even malformations, matches that of the gold standard hysteroscopy. This chapter lists out specific imaging examples for submucous myoma, endometrial polyp, blood clot, endometrial malignancy, intrauterine synechia and congenital uterine anomaly. It outlines three-dimensional saline infusion sonohysterography (SIS), sonosalpingography or hysterosalpingo-contrast sonography, operative SIS, and sonovaginography. Combining TVS with vaginal saline infusion may improve the ability to image structures surrounding the vagina, such as the rectovaginal septum for endometriosis.
Acute pelvic pain is a common reason for women to seek urgent gynecologic evaluation. Although the classic clinical presentation is dysmenorrhea with premenstrual intensification, dyspareunia, and chronic pelvic pain, some patients, who may or may not know they have the condition, experience acute pelvic pain. Ovarian hyperstimulation syndrome (OHSS) is an iatrogenic complication of superovulation induction therapy with a varied spectrum of clinical and laboratory manifestations. Crampy pelvic pain due to hormonal changes, rapid growth of the uterus, and increased blood flow is a common sign of early pregnancy. If a patient fails a single course of methotrexate or has pelvic pain that is increasing, ultrasound can be helpful. If a patient continues to have pain after a presumed miscarriage, even if products of conception were confirmed cytologically, a heterotopic pregnancy should be a considered.
Placental nutrient transfer capacity increases over gestation by increased placental growth, primarily of membrane surface area, allowing for the increase in nutrient supply required for the growing fetus. Glucose is the primary energy substrate for the mammalian fetus and placenta. The fetus metabolizes glucose in several ways, including oxidation for energy requirements and as a carbon source for production of various macromolecules, such as glycogen, glycolytic products, proteins, and fatty acids. Total nitrogen concentration measurements have been used to estimate the rate of protein accretion in tissues, because most of the total nitrogen is represented by amino acid nitrogen uptake. The net uptake of amino acids by umbilical circulation through the placenta represents the dietary supply of amino acids for fetal growth and protein metabolism. The transport of fatty acids and other lipid substances across the placenta and the deposition of lipids in fetal adipose tissue are primarily late-gestation phenomena.