At present a small number of full-scale marine current energy converters are undergoing sea trials to demonstrate commercial viability of the technology. In order to provide meaningful quantities of ...electrical power to the grid, the next phase in the development of the technology will be the installation and operation of farms or arrays composed of multiple devices. As most tidal current sites are bi-directional and with bathymetry constraints, array layouts will necessarily take the form of highly optimized geometric configurations with reduced lateral inter-device spacing. This work discusses the concept of array layouts and proposes an appropriate and clear classification that can aid developers in understanding how arrays operate. This classification is supported by experimental studies conducted using several arrangements of multiple actuator disks to simulate early generation marine current energy converter arrays. The work presents quantification of the flow field around a 2-row array, device/device interaction as well as a study of the structure of the far wake region where subsequent devices could be installed. The results highlight an optimal lateral spacing between devices where, under certain conditions flow can be accelerated between a pair of rotor disks. For the work presented here this accelerated region of flow possessed 22% more kinetic energy than the flow far upstream with no measurable negative effect upon the 2 actuator disks. This enhanced flow speed gives rise to the counterintuitive notion of a downstream row of devices producing more power than the upstream row. This will lead to a synergistic effect whereby an array of devices can generate more power than an equivalent number of isolated machines.
► Multiple-row tidal turbine experiments conducted. ► High resolution flow mapping of array. ► Demonstrated fluid can be accelerated between adjacent devices. ► Available Kinetic energy 22% greater to downstream devices. ► Proves that synergy between devices can be achieved to increase array power output.
There is conflicting evidence regarding the effect of coronavirus disease (COVID-19) in pregnancy. Risk factors for COVID-19 overlap with risk factors for pregnancy complications. We aimed to assess ...the effects of the COVID-19 pandemic and confirmed SARS-CoV-2 infection on pregnancy outcomes. A retrospective interrupted time-series and matched cohort analysis was performed. Singleton pregnancies completed between 1st January 2016 and 31st January 2021 were included. Trends in outcomes were analysed over time. Modelled COVID-19 transmission data were applied to deliveries since 1st January 2020 to assign a risk of COVID-19 to each pregnancy, and incorporated into a regression model of birthweight. Confirmed COVID-19 cases were matched to controls delivered in the pre-pandemic period, and maternal and neonatal outcomes compared. 43,802 pregnancies were included, with 8343 in the model of birthweight. There was no increase in the risk of stillbirth (p = 0.26) or neonatal death (p = 0.64) during the pandemic. There was no association between modelled COVID-19 attack rate (%) in any trimester and birthweight (first trimester p = 0.50, second p = 0.15, third p = 0.16). 214 COVID-positive women were matched to controls. Preterm birth was more common in symptomatic cases (14/62, 22.6%) compared to asymptomatic cases (9/109, 8.3%, p = 0.008) and controls (5/62, 8.1%, p = 0.025). Iatrogenic preterm birth was more common in cases (21/214, 9.8%) than controls (9/214, 4.2%, p = 0.02). All other examined outcomes were similar between groups. There was no significant impact of COVID-19 on the examined birth outcomes available. Symptomatic COVID-19 should be considered a risk factor for preterm birth, possibly due to an increase in iatrogenic deliveries for maternal indications.
Purpose
Circulating tumor cell (CTC) is a well-established prognosis predictor for metastatic breast cancer (MBC), and CTC-cluster exhibits significantly higher metastasis-promoting capability than ...individual CTCs. Because measurement of CTCs and CTC-clusters at a single time point may underestimate their prognostic values, we aimed to analyze longitudinally collected CTCs and CTC-clusters in MBC prognostication.
Methods
CTCs and CTC-clusters were enumerated in 370 longitudinally collected blood samples from 128 MBC patients. The associations between baseline, first follow-up, and longitudinal enumerations of CTCs and CTC-clusters with patient progression-free survival (PFS) and overall survival (OS) were analyzed using Cox proportional hazards models.
Results
CTC and CTC-cluster counts at both baseline and first follow-up were significantly associated with patient PFS and OS. Time-dependent analysis of longitudinally collected samples confirmed the significantly unfavorable PFS and OS in patients with ≥5 CTCs, and further demonstrated the independent prognostic values by CTC-clusters compared to CTC-enumeration alone. Longitudinal analyses also identified a link between the size of CTC-clusters and patient OS: compared to the patients without any CTC, those with 2-cell CTC-clusters and ≥3-cell CTC-clusters had a hazard ratio (HR) of 7.96 95 % confidence level (CI) 2.00–31.61,
P
= 0.003 and 14.50 (3.98–52.80,
P
< 0.001), respectively.
Conclusions
In this novel time-dependent analysis of longitudinally collected CTCs and CTC-clusters, we showed that CTC-clusters added additional prognostic values to CTC enumeration alone, and a larger-size CTC-cluster conferred a higher risk of death in MBC patients.
This retrospective cross-sectional study aimed to identify opportunities for improvement in food and nutrition research by examining risk of bias (ROB) domains.
Ratings were extracted from critical ...appraisal records for 5675 studies used in systematic reviews conducted by three organizations. Variables were as follows: ROB domains defined by the Cochrane Collaboration (Selection, Performance, Detection, Attrition, and Reporting), publication year, research type (intervention or observation) and specific design, funder, and overall quality rating (positive, neutral, or negative). Appraisal instrument questions were mapped to ROB domains. The kappa statistic was used to determine consistency when multiple ROB ratings were available. Binary logistic regression and multinomial logistic regression were used to predict overall quality and ROB domains.
Studies represented a wide variety of research topics (clinical nutrition, food safety, dietary patterns, and dietary supplements) among 15 different research designs with a balance of intervention (49%) and observation (51%) types, published between 1930 and 2015 (64% between 2000-2009). Duplicate ratings (10%) were consistent (κ = 0.86-0.94). Selection and Performance domain criteria were least likely to be met (57.9% to 60.1%). Selection, Detection, and Performance ROB ratings predicted neutral or negative quality compared to positive quality (p<0.001). Funder, year, and research design were significant predictors of ROB. Some sources of funding predicted increased ROB (p<0.001) for Selection (interventional: industry only and none/not reported; observational: other only and none/not reported) and Reporting (observational: university only and other only). Reduced ROB was predicted by combined and other-only funding for intervention research (p<0.005). Performance ROB domain ratings started significantly improving in 2000; others improved after 1990 (p<0.001). Research designs with higher ROB were nonrandomized intervention and time series designs compared to RCT and prospective cohort designs respectively (p<0.001).
Opportunities for improvement in food and nutrition research are in the Selection, Performance, and Detection ROB domains.
Abstract Background Phenotypic presentations in young children with asthma are varied and may contribute to differential responses to asthma controller medications. Methods The Individualized Therapy ...for Asthma in Toddlers (INFANT) study was a multicenter, randomized, double-blind, double-dummy, clinical trial in children age 12-59 months (n=300) with asthma necessitating treatment with daily controller (Step 2) therapy. Participants completed a 2-8 week run-in period followed by three crossover periods with daily inhaled corticosteroid (ICS) , daily leukotriene receptor antagonist (LTRA) , and as-needed ICS treatment co-administered with albuterol. The primary outcome was differential response to asthma medication based on a composite measure of asthma control. The primary analysis involved two stages: determination of differential response, and assessment of whether three pre-specified features (aeroallergen sensitization, previous exacerbations, sex) predicted differential response. Results 74% (170 of 230) of children with analyzable data had a differential response to the three treatment strategies. Within differential responders, the probability of best response was highest for daily ICS and was predicted by aeroallergen sensitization, but not exacerbation history or sex. The probability of best response to daily ICS was further increased in children with both aeroallergen sensitization and blood eosinophils ≥300/μL. In these children, daily ICS was associated with more asthma control days and fewer exacerbations compared to the other treatments. Conclusions In young children with asthma necessitating Step 2 treatment, phenotyping with aeroallergen sensitization and blood eosinophils is useful for guiding treatment selection and identifies children with a high exacerbation probability for whom treatment with daily ICS is beneficial despite possible risks of growth suppression.
We have developed arrays of nanomechanical systems (NEMS) by large-scale integration, comprising thousands of individual nanoresonators with densities of up to 6 million NEMS per square centimeter. ...The individual NEMS devices are electrically coupled using a combined series-parallel configuration that is extremely robust with respect to lithographical defects and mechanical or electrostatic-discharge damage. Given the large number of connected nanoresonators, the arrays are able to handle extremely high input powers (>1 W per array, corresponding to <1 mW per nanoresonator) without excessive heating or deterioration of resonance response. We demonstrate the utility of integrated NEMS arrays as high-performance chemical vapor sensors, detecting a part-per-billion concentration of a chemical warfare simulant within only a 2 s exposure period.
Infrapatellar fat pad adipose stem cells (IPFP-ASCs) have been shown to harbor chondrogenic potential. When combined with 3D polymeric structures, the stem cells provide a source of stem cells to ...engineer 3D tissues for cartilage repair. In this study, we have shown human IPFP-ASCs seeded onto 3D printed chitosan scaffolds can undergo chondrogenesis using TGFβ3 and BMP6. By week 4, a pearlescent, cartilage-like matrix had formed that penetrated the top layers of the chitosan scaffold forming a 'cap' on the scaffold. Chondrocytic morphology showed typical cells encased in extracellular matrix which stained positively with toluidine blue. Immunohistochemistry demonstrated positive staining for collagen type II and cartilage proteoglycans, as well as collagen type I. Real time PCR analysis showed up-regulation of collagen type II, aggrecan and SOX9 genes when IPFP-ASCs were stimulated by TGFβ3 and BMP6. Thus, IPFP-ASCs can successfully undergo chondrogenesis using TGFβ3 and BMP6 and the cartilage-like tissue that forms on the surface of 3D-printed chitosan scaffold may prove useful as an osteochondral graft.
Repeated elements such as satellites and transposons are ubiquitous in eukaryotic genomes. De novo computational identification and classification of such elements is a challenging problem. ...Therefore, repeat annotation of sequenced genomes has historically largely relied on sequence similarity to hand-curated libraries of known repeat families. We present a new approach to de novo repeat annotation that exploits characteristic patterns of local alignments induced by certain classes of repeats. We describe PILER, a package of efficient search algorithms for identifying such patterns. Novel repeats found using PILER are reported for Homo sapiens, Arabidopsis thalania and Drosophila melanogaster. Availability: The PILER software is freely available at http://www.drive5.com/piler Contact: bob@drive5.com
Parkinson's disease is characterized by the degeneration of dopaminergic pathways projecting to the striatum. These pathways are implicated in reward prediction. In this study, we investigated reward ...and punishment processing in young, never-medicated Parkinson's disease patients, recently medicated patients receiving the dopamine receptor agonists pramipexole and ropinirole and healthy controls. The never-medicated patients were also re-evaluated after 12 weeks of treatment with dopamine agonists. Reward and punishment processing was assessed by a feedback-based probabilistic classification task. Personality characteristics were measured by the temperament and character inventory. Results revealed that never-medicated patients with Parkinson's disease showed selective deficits on reward processing and novelty seeking, which were remediated by dopamine agonists. These medications disrupted punishment processing. In addition, dopamine agonists increased the correlation between reward processing and novelty seeking, whereas these drugs decreased the correlation between punishment processing and harm avoidance. Our finding that dopamine agonist administration in young patients with Parkinson's disease resulted in increased novelty seeking, enhanced reward processing, and decreased punishment processing may shed light on the cognitive and personality bases of the impulse control disorders, which arise as side-effects of dopamine agonist therapy in some Parkinson's disease patients.
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