ABSTRACT
The use of acoustic Doppler current profilers (ADCP) for discharge measurements and three‐dimensional flow mapping has increased rapidly in recent years and has been primarily driven by ...advances in acoustic technology and signal processing. Recent research has developed a variety of methods for processing data obtained from a range of ADCP deployments and this paper builds on this progress by describing new software for processing and visualizing ADCP data collected along transects in rivers or other bodies of water. The new utility, the Velocity Mapping Toolbox (VMT), allows rapid processing (vector rotation, projection, averaging and smoothing), visualization (planform and cross‐section vector and contouring), and analysis of a range of ADCP‐derived datasets. The paper documents the data processing routines in the toolbox and presents a set of diverse examples that demonstrate its capabilities. The toolbox is applicable to the analysis of ADCP data collected in a wide range of aquatic environments and is made available as open‐source code along with this publication. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.
► We used EEG to compare problem gamblers and controls in a modified Iowa Gambling Task. ► Gamblers an early FRN – like ERP component. ► Early FRN amplitude was correlated with gambling severity. ► ...Evidence of sensitization to reward in problem gamblers.
Problem gambling (PG) is increasingly conceptualized as an addiction akin to substance abuse, rather than an impulse control disorder, however the mechanism of addiction remains unclear. Neuroimaging investigations have supported a “reward deficiency” hypothesis for PG by suggesting a blunted response to gambling, particularly in the striatum. Here we describe electrophysiological evidence of a hypersensitive response to gambling feedback in problem gamblers. Previous research in healthy participants has shown that feedback during gambling tasks triggers stereotypical neural responses including the Feedback-Related Mediofrontal Negativity (FRN), the feedback-related P300, and an increase in induced theta-band (4–8Hz) power. We tested the theory that abnormal feedback processing characterizes brain activity in problem gamblers while gambling. EEG was recorded from non-gamblers and self-identified gamblers as they engaged in a computerized version of the Iowa Gambling Task. Feedback about valence (win vs. loss) triggered a FRN in both groups, but in gamblers this was preceded by an early-latency hypersensitive fronto-central difference to feedback. This early FRN was correlated with gambling severity and was localized to medial frontal cortex using distributed source imaging (CLARA). Gamblers also differed in responses to risk, showing a blunted P300 component and less EEG power in the theta band. Here we suggest that a more nuanced interpretation of reward deficiency is called for with respect to PG. For certain aspects of brain function, gamblers may exhibit hypersensitivity to reward feedback more akin to drug sensitization than reward deficiency. Our results also suggest that the neurologically normal brain employs dissociable systems in the processing of feedback from tasks involving risky decision making.
To assess whether the use of assisted reproductive technology (ART) therapy for conception is associated with imprinting disorders in children and the impact of parental factors related to ...infertility.
A nationwide register-based cohort study.
Swedish national registers and nationwide quality IVF register.
All liveborn singletons in Sweden (N = 2,084,127) between 1997 and 2017 with follow-up to December 31, 2018.
The use of specific methods implemented in ART.
The International Classification of Diseases version 10 was used to identify three distinct imprinting disorder groups: Beckwith-Wiedemann syndrome (BWS), Prader-Willi syndrome (PWS), and Silver-Russell syndrome (SRS), as well as central precocious puberty. The Cox model combined with inverse probability treatment weights was used to estimate the weighted hazard ratio (wHR) with a 95% confidence interval (CI), accounting for multiple confounders.
A total of 1,044 children were diagnosed with the disorders of interest, and 52 of them were conceived using ART therapy. The overall risk of being diagnosed with any of the studied imprinting disorders was elevated in children conceived using ART therapy compared with all other children (HR, 1.84; 95% CI, 1.38–2.45). After adjusting for parental background factors, the association was partially attenuated (wHR, 1.50; 95% CI, 0.97–2.32), but remained in the weighted comparison restricted to children of couples with known infertility (wHR, 1.52; 95% CI, 1.05–2.21). For the specific diagnoses of PWS/SRS, and BWS compared with children of couples with known infertility, children conceived with ART therapy showed a small excess risk, which could not be distinguished from the null (wHR, 1.56; 95% CI, 0.93–2.62 and 1.80; 95% CI, 0.99–3.28, respectively). Further subgroup analysis showed that the combined use of intracytoplasmic sperm injection and cryopreserved embryos was associated with a higher risk of both PWS/SRS (wHR, 4.60; 95% CI, 1.72–12.28) and BWS (wHR, 6.69; 95% CI, 2.09–21.45). The number of central precocious puberty cases in children conceived using ART therapy was too small (N = 3) to make any meaningful inference.
The combined use of intracytoplasmic sperm injection and cryopreserved embryos was associated with small elevated risks of PWS/SRS, and BWS in children, independent of parental factors related to infertility.
To test the ability of acoustic Doppler current profilers (ADCPs) to measure turbulence, profiles measured with two pulse-to-pulse coherent ADCPs in a laboratory flume were compared to profiles ...measured with an acoustic Doppler velocimeter, and time series measured in the acoustic beam of the ADCPs were examined. A four-beam ADCP was used at a downstream station, while a three-beam ADCP was used at a downstream station and an upstream station. At the downstream station, where the turbulence intensity was low, both ADCPs reproduced the mean velocity profile well away from the flume boundaries; errors near the boundaries were due to transducer ringing, flow disturbance, and sidelobe interference. At the upstream station, where the turbulence intensity was higher, errors in the mean velocity were large. The four-beam ADCP measured the Reynolds stress profile accurately away from the bottom boundary, and these measurements can be used to estimate shear velocity. Estimates of Reynolds stress with a three-beam ADCP and turbulent kinetic energy with both ADCPs cannot be computed without further assumptions, and they are affected by flow inhomogeneity. Neither ADCP measured integral time scales to within 60%.
Individuals conceived with assisted reproductive techniques (ARTs) could be at elevated risk of psychiatric disorders owing to potential adverse effects of the procedures themselves, or because such ...traits or their risk factors may be more common in couples with infertility.
To investigate the risk of psychiatric disorders in adolescents and young adults conceived with ARTs and to evaluate the role of treatment-related parental characteristics.
This prospective follow-up of a nationwide birth cohort used linkage of Swedish population registers with coverage through 2018. All children born in Sweden from January 1, 1994, to December 31, 2006, were included in the analysis. Follow-up was completed on December 31, 2018, when participants were 12 to 25 years of age, and data was analyzed from March 17, 2020, to September 10, 2021.
In vitro fertilization with or without intracytoplasmic sperm injection and transfer of fresh or frozen-thawed embryos.
Clinical diagnoses of mood disorder, including major depression, anxiety, obsessive-compulsive disorder (OCD), or suicidal behavior, were identified from hospital records and outpatient specialist care. Suicide was additionally identified from death certificates. Antidepressant use was identified from dispensations of prescribed medications.
A total of 1 221 812 children (48.6% female, 51.4% male) born between 1994 and 2006 were followed up to a median age of 18 (IQR, 15-21) years. Among these participants, 31 565 (2.6%) were conceived with ART. Compared with all others, adolescents conceived with ART had an elevated risk of OCD (hazard ratio HR, 1.35 95% CI, 1.20-1.51), but the association was attenuated and no longer statistically significant after adjustment for parental characteristics (adjusted HR aHR, 1.10 95% CI, 0.98-1.24) and was no longer present when restricted to individuals born to couples with known infertility (aHR, 1.02 95% CI, 0.89-1.17). Adolescents conceived with ARTs were not at elevated risk of depression or suicidal behavior compared with other adolescents (irrespective of parental infertility). Type of fertilization (standard in vitro fertilization or intracytoplasmic sperm injection) had no association with outcomes. Compared with non-ART-conceived children of couples with infertility, fresh, but not frozen, embryo transfer was associated with a lower risk of mood disorders (aHR, 0.90 95% CI, 0.83-0.97), making frozen embryo transfer appear less advantageous when directly contrasted with fresh embryo transfer.
These findings suggest that adolescents conceived with ARTs around the millennium are not at risk of poor psychiatric health compared with the general population, except for an elevated risk of OCD that may be explained by differences in parental characteristics.
Pregnancies resulting from assisted reproductive technology are associated with an increased risk of adverse perinatal outcomes compared with those following natural conception. Previous studies have ...shown an association of pregnancies resulting from transfer of multiple embryos with these negative findings.
To determine the risk for adverse outcomes in singletons conceived through assisted reproduction using double-embryo transfer (DET) vs single-embryo transfer (SET).
This cohort study used data from women who achieved singleton deliveries after SET or DET in Sweden between 2007 and 2017 as recorded in the National Quality Registry for Assisted Reproduction. All embryo transfers, at cleavage or blastocyst stage, replaced in fresh or frozen treatment cycles were included. Data on obstetric and neonatal outcomes were retrieved by linkage to the National Medical Birth Register. Naturally conceived singletons were included as a reference group. Data were analyzed between September 2021 and August 2022.
Double-embryo transfer leading to singleton birth.
Relative risk ratios or odds ratios (ORs) and absolute risk differences (ARDs) in percentage points with 95% CIs were calculated for obstetric and perinatal outcomes in singleton births conceived using DET vs SET.
Among 1 115 863 singleton births, 30 713 singletons were born after SET and 5123 after DET. A higher risk of neonatal death was found in singletons after DET vs SET (OR, 2.67 95% CI, 1.28-5.55; ARD, 0.2 percentage points 95% CI, 0.0-0.4 percentage points). In frozen embryo transfers, DET was associated with a higher risk of low birth weight (OR, 1.64 95% CI, 1.19-2.25; ARD, 2.0 percentage points 95% CI, 0.5-3.5 percentage points). Among blastocyst transfers, DET was associated with very preterm birth (relative risk ratio, 2.64 95% CI, 1.50-4.63; ARD, 1.8 percentage points 95% CI, 0.3-3.4 percentage points) and low birth weight (OR, 1.83 95% CI, 1.29-2.60; ARD, 3.2 percentage points 95% CI, 0.9-5.5 percentage points).
These results indicate a higher risk of adverse outcomes following DET, even when the result is a singleton birth, vs singletons born after SET. Adverse outcomes were mainly observed in singletons following DET using frozen embryos and blastocysts.
Bidirectional flows in a river system can occur under stratified flow conditions and in addition to creating significant errors in discharge estimates, the upstream propagating currents are capable ...of transporting contaminants and affecting water quality. Detailed field observations of bidirectional flows were made in the Chicago River in Chicago, Illinois in the winter of 2005–06. Using multiple acoustic Doppler current profilers simultaneously with a water-quality profiler, the formation of upstream propagating density currents within the Chicago River both as an underflow and an overflow was observed on three occasions. Density differences driving the flow primarily arise from salinity differences between intersecting branches of the Chicago River, whereas water temperature is secondary in the creation of these currents. Deicing salts appear to be the primary source of salinity in the North Branch of the Chicago River, entering the waterway through direct runoff and effluent from a wastewater-treatment plant in a large metropolitan area primarily served by combined sewers. Water-quality assessments of the Chicago River may underestimate (or overestimate) the impairment of the river because standard water-quality monitoring practices do not account for density-driven underflows (or overflows). Chloride concentrations near the riverbed can significantly exceed concentrations at the river surface during underflows indicating that full-depth parameter profiles are necessary for accurate water-quality assessments in urban environments where application of deicing salt is common.
Abnormal filaments consisting of hyperphosphorylated microtubule-associated protein tau form in the brains of patients with Alzheimer's disease, Down's syndrome, and various dementing tauopathies. In ...Alzheimer's disease and Down's syndrome, the filaments have two characteristic morphologies referred to as paired helical and straight filaments, whereas in tauopathies, there is a wider range of morphologies. There has been controversy in the literature concerning the internal molecular fine structure of these filaments, with arguments for and against the cross-β structure demonstrated in many other amyloid fibers. The difficulty is to produce from brain pure preparations of filaments for analysis. One approach to avoid the need for a pure preparation is to use selected area electron diffraction from small groups of filaments of defined morphology. Alternatively, it is possible to assemble filaments in vitro from expressed tau protein to produce a homogeneous specimen suitable for analysis by electron diffraction, x-ray diffraction, and Fourier transform infrared spectroscopy. Using both these approaches, we show here that native filaments from brain and filaments assembled in vitro from expressed tau protein have a clear cross-β structure.
Acoustic Doppler current profilers (ADCPs) are commonly used to measure streamflow and water velocities in rivers and streams. This paper presents laboratory, field, and numerical model evidence of ...errors in ADCP measurements caused by flow disturbance. A state-of-the-art three-dimensional computational fluid dynamic model is validated with and used to complement field and laboratory observations of flow disturbance and its effect on measured velocities. Results show that near the instrument, flow velocities measured by the ADCP are neither the undisturbed stream velocity nor the velocity of the flow field around the ADCP. The velocities measured by the ADCP are biased low due to the downward flow near the upstream face of the ADCP and upward recovering flow in the path of downstream transducer, which violate the flow homogeneity assumption used to transform beam velocities into Cartesian velocity components. The magnitude of the bias is dependent on the deployment configuration, the diameter of the instrument, and the approach velocity, and was observed to range from more than 25% at
5
cm
from the transducers to less than 1% at about
50
cm
from the transducers for the scenarios simulated.
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