This paper describes the development and validation of a statistical algorithm to retrieve global all-weather sea surface wind speeds (GAWS) from microwave radiometers in operational environment. ...Measurements from the Advanced Microwave Scanning Radiometer-2 (AMSR2) are utilized to demonstrate the efficacy of the new all-weather wind speed data product. The GAWS algorithm exploits the linear combination of dual-polarized radiometer channels to significantly mitigate the effect of rain contamination while maintaining sensitivity to all wind speed regimes from global winds to tropical cyclone conditions. The GAWS algorithm was developed using ~1000 AMSR2 orbits from 2013 - 2021 covering all possible variations of brightness temperatures and wind speeds. The Global Data Assimilation System (GDAS) and the Hurricane Weather Research and Forecasting Model (HWRF) were used as the assumed surface truth for training and validation. Results from comprehensive quantitative and qualitative analyses show that GAWS retrievals are less susceptible to rain than standard microwave radiometer wind speeds and can reach hurricane force winds up to hurricane category 5 (> 70 m/s).
A novel approach in addressing cyclone global navigation satellite system (CyGNSS) intersatellite and GPS-related calibration issues is proposed, based on a track-wise <inline-formula> <tex-math ...notation="LaTeX">\sigma ^{o} </tex-math></inline-formula> bias correction method. This method makes use of both ancillary data from numerical weather prediction models and a semiempirical geophysical model function. Care is taken, so the track-wise <inline-formula> <tex-math notation="LaTeX">\sigma ^{o} </tex-math></inline-formula> bias correction maintains CyGNSS signal sensitivity. Both intersatellite and GPS-related calibration issues are removed after correction. Long-term <inline-formula> <tex-math notation="LaTeX">\sigma ^{o} </tex-math></inline-formula> downward trend, observed throughout the CyGNSS mission, is greatly reduced. Using the corrected <inline-formula> <tex-math notation="LaTeX">\sigma ^{o} </tex-math></inline-formula> measurements, a wind retrieval method is also presented and its product thoroughly assessed for a three-year period against European Centre for Medium-Range Weather Forecasts (ECMWFs), Advanced Scatterometer (ASCAT) A/B, Advanced Microwave Scanning Radiometer (AMSR)-2, GMI, WindSat, hurricane weather research and forecasting (HWRF) model, and the stepped frequency microwave radiometer (SFMR) winds. The overall wind speed bias and standard deviation of the error (stde) against ECMWF are 0.16 and 1.19 m/s, while these are −0.11 and 1.12 m/s against ASCAT A/B, respectively. The same metrics against AMSR-2/GMI/WindSat (combined) are −0.19 and 1.11 m/s, respectively. The bias and stde against soil moisture active passive (SMAP) are −0.38 and 1.90 m/s, respectively. In the tropical cyclone environment, the bias and stde against HWRF are −0.54 and 2.90 m/s, and −4.71 and 5.88 m/s with SFMR. Finally, CyGNSS wind performance is gauged in the presence of rain. Below 10 m/s, the bias between CyGNSS and ECMWF increases as the rain rate increases. Between 10 and 15 m/s, biases are mostly absent. Above 15 m/s, results are inconclusive due to the low number of collocated rain samples. Overall, the presented CyGNSS wind speed product both exhibits consistency and reliability, showing promise of using GNSS-R derived winds for operational purposes.
Artificial intelligence (AI) has the potential to transform the clinical practice of radiology. This study investigated Canadian medical students' perceptions of the impact of AI on radiology, and ...their influence on the students' preference for radiology specialty.
In March 2018, an anonymous online survey was distributed to students at all 17 Canadian medical schools.
Among 322 respondents, 70 students considered radiology as the top specialty choice, and 133 as among the top three choices. Only a minority (29.3%) of respondents agreed AI would replace radiologists in foreseeable future, but a majority (67.7%) agreed AI would reduce the demand for radiologists. Even among first-choice respondents, 48.6% agreed AI caused anxiety when considering the radiology specialty. Furthermore, one-sixth of respondents who would otherwise rank radiology as the first choice would not consider radiology because of the anxiety about AI. Prior significant exposure to radiology and high confidence in understanding of AI were shown to decrease the anxiety level. Interested students valued the opinions of local radiologists, radiology conferences, and journals. Students were most interested in "expert opinions on AI" and "discussing AI in preclinical radiology lectures" to understand the impact of AI.
Anxiety related to "displacement" (not "replacement") of radiologists by AI discouraged many medical students from considering the radiology specialty. The radiology community should educate medical students about the potential impact of AI, to ensure radiology is perceived as a viable long-term career choice.
Abstract
Although the concept of protest cycles has received much attention in the collective action literature, its empirical operationalization remains relatively crude compared to the rich ...theoretical discussion. Reimagining social movements as populations of interlinked protests, we demonstrate the advantages of analyzing protest event networks with a novel dataset related to South Korea’s democracy movement. In our conceptualization, protest events play the role of network nodes and links were identified based on protesters citing prior events as sources of inspiration for mobilizing. Appropriating strategies for network analysis, we assess the types of events that were more likely to be cited as sources of inspiration and bridge otherwise disconnected events. Our analysis shows that protests that raised systemic versus local issues and events that were repressed by the state were more likely to occupy central positions in the democracy movement. By identifying the characteristics of events that contribute to movement inspiration and bridging, our novel approach to analyzing protest events sheds new light on dominant themes in social movement research.
Poly(ADP‐ribose) polymerases (PARPs) regulate the function of target proteins by modifying them with ADP‐ribose, a large and unique post‐translational modification. Humans express 17 PARPs; however, ...historically, much of the focus has been on PARP1 and its function in DNA damage repair. Recent work has uncovered an amazing diversity of function for these enzymes including the regulation of fundamental physiological processes in the cell and at the organismal level, as well as new roles in regulating cellular stress responses. In this review, we discuss recent advancements in our understanding of this important protein family, and technological developments that have been critical for moving the field forward. Finally, we discuss new directions that we feel are important areas of further scientific exploration.
PARPs modify target proteins with a unique post‐translational modification called ADP‐ribose. Modification of target proteins plays important roles in multiple cellular pathways including differentiation, RNA regulation, protein degradation, and cellular stress responses. Recently, several new PARP functions have been identified that we summarize in this review. Given that most of the PARPs remain unexplored, additional functions are sure to come.
The poly(adenosine diphosphate (ADP)-ribose) polymerase (PARP) protein family generates ADP-ribose (ADPr) modifications onto target proteins using NAD(+) as substrate. Based on the composition of ...three NAD(+) coordinating amino acids, the H-Y-E motif, each PARP is predicted to generate either poly(ADPr) (PAR) or mono(ADPr) (MAR). However, the reaction product of each PARP has not been clearly defined, and is an important priority since PAR and MAR function via distinct mechanisms. Here we show that the majority of PARPs generate MAR, not PAR, and demonstrate that the H-Y-E motif is not the sole indicator of PARP activity. We identify automodification sites on seven PARPs, and demonstrate that MAR and PAR generating PARPs modify similar amino acids, suggesting that the sequence and structural constraints limiting PARPs to MAR synthesis do not limit their ability to modify canonical amino-acid targets. In addition, we identify cysteine as a novel amino-acid target for ADP-ribosylation on PARPs.
Obesity and GERD Chang, Paul; Friedenberg, Frank
Gastroenterology clinics of North America,
03/2014, Letnik:
43, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Epidemiologic data have demonstrated that obesity is an important risk factor for the development of gastroesophageal reflux disease (GERD). There is also accumulating data that obesity is associated ...with complications related to longstanding reflux such as erosive esophagitis, Barrett esophagus, and esophageal adenocarcinoma. Central obesity, rather than body mass index, appears to be more closely associated with these complications. Surgical data are confounded by the concomitant repair of prevalent hiatal hernias in many patients.
The poly(ADP-ribose) polymerase (PARP) family of proteins use NAD(+) as their substrate to modify acceptor proteins with ADP-ribose modifications. The function of most PARPs under physiological ...conditions is unknown. Here, to better understand this protein family, we systematically analyse the cell cycle localization of each PARP and of poly(ADP-ribose), a product of PARP activity, then identify the knockdown phenotype of each protein and perform secondary assays to elucidate function. We show that most PARPs are cytoplasmic, identify cell cycle differences in the ratio of nuclear to cytoplasmic poly(ADP-ribose) and identify four phenotypic classes of PARP function. These include the regulation of membrane structures, cell viability, cell division and the actin cytoskeleton. Further analysis of PARP14 shows that it is a component of focal adhesion complexes required for proper cell motility and focal adhesion function. In total, we show that PARP proteins are critical regulators of eukaryotic physiology.
Many patients with diabetic peripheral neuropathy experience chronic pain and inadequate relief despite best available medical treatments.
To determine whether 10-kHz spinal cord stimulation (SCS) ...improves outcomes for patients with refractory painful diabetic neuropathy (PDN).
The prospective, multicenter, open-label SENZA-PDN randomized clinical trial compared conventional medical management (CMM) with 10-kHz SCS plus CMM. Participants with PDN for 1 year or more refractory to gabapentinoids and at least 1 other analgesic class, lower limb pain intensity of 5 cm or more on a 10-cm visual analogue scale (VAS), body mass index (calculated as weight in kilograms divided by height in meters squared) of 45 or less, hemoglobin A1c (HbA1c) of 10% or less, daily morphine equivalents of 120 mg or less, and medically appropriate for the procedure were recruited from clinic patient populations and digital advertising. Participants were enrolled from multiple sites across the US, including academic centers and community pain clinics, between August 2017 and August 2019 with 6-month follow-up and optional crossover at 6 months. Screening 430 patients resulted in 214 who were excluded or declined participation and 216 who were randomized. At 6-month follow-up, 187 patients were evaluated.
Implanted medical device delivering 10-kHz SCS.
The prespecified primary end point was percentage of participants with 50% pain relief or more on VAS without worsening of baseline neurological deficits at 3 months. Secondary end points were tested hierarchically, as prespecified in the analysis plan. Measures included pain VAS, neurological examination, health-related quality of life (EuroQol Five-Dimension questionnaire), and HbA1c over 6 months.
Of 216 randomized patients, 136 (63.0%) were male, and the mean (SD) age was 60.8 (10.7) years. Additionally, the median (interquartile range) duration of diabetes and peripheral neuropathy were 10.9 (6.3-16.4) years and 5.6 (3.0-10.1) years, respectively. The primary end point assessed in the intention-to-treat population was met by 5 of 94 patients in the CMM group (5%) and 75 of 95 patients in the 10-kHz SCS plus CMM group (79%; difference, 73.6%; 95% CI, 64.2-83.0; P < .001). Infections requiring device explant occurred in 2 patients in the 10-kHz SCS plus CMM group (2%). For the CMM group, the mean pain VAS score was 7.0 cm (95% CI, 6.7-7.3) at baseline and 6.9 cm (95% CI, 6.5-7.3) at 6 months. For the 10-kHz SCS plus CMM group, the mean pain VAS score was 7.6 cm (95% CI, 7.3-7.9) at baseline and 1.7 cm (95% CI, 1.3-2.1) at 6 months. Investigators observed neurological examination improvements for 3 of 92 patients in the CMM group (3%) and 52 of 84 in the 10-kHz SCS plus CMM group (62%) at 6 months (difference, 58.6%; 95% CI, 47.6-69.6; P < .001).
Substantial pain relief and improved health-related quality of life sustained over 6 months demonstrates 10-kHz SCS can safely and effectively treat patients with refractory PDN.
ClincalTrials.gov Identifier: NCT03228420.
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