421 research outputs found
Population transcriptomics reveals weak parallel genetic basis in repeated marine and freshwater divergence in nine-spined sticklebacks
Abstract The degree to which adaptation to similar selection pressures is underlain by parallel vs. non-parallel genetic changes is a topic of broad interest in contemporary evolutionary biology. Sticklebacks provide opportunities to characterize and compare the genetic underpinnings of repeated marine-freshwater divergences at both intra- and interspecific levels. While the degree of genetic parallelism in repeated marine-freshwater divergences has been frequently studied in the three-spined stickleback (Gasterosteus aculeatus), much less is known about this in other stickleback species. Using a population transcriptomic approach, we identified both genetic and gene expression variations associated with marine-freshwater divergence in the nine-spined stickleback (Pungitius pungitius). Specifically, we used a genome-wide association study approach, and found that ~1% of the total 173,491 identified SNPs showed marine-freshwater ecotypic differentiation. A total of 861 genes were identified to have SNPs associated with marine-freshwater divergence in nine-spined stickleback, but only 12 of these genes have also been reported as candidates associated with marine-freshwater divergence in the three-spined stickleback. Hence, our results indicate a low degree of interspecific genetic parallelism in marine-freshwater divergence. Moreover, 1,578 genes in the brain and 1,050 genes in the liver were differentially expressed between marine and freshwater nine-spined sticklebacks, ~5% of which have also been identified as candidates associated with marine-freshwater divergence in the three-spined stickleback. However, only few of these (e.g., CLDND1) appear to have been involved in repeated marine-freshwater divergence in nine-spined sticklebacks. Taken together, the results indicate a low degree of genetic parallelism in repeated marine-freshwater divergence both at intra- and interspecific levels.Peer reviewe
The Effect of Exercise on Pulpal and Gingival Blood Flow in Physically Active and Inactive Subjects as Assessed by Laser Doppler
The effects of exercise on pulpal and gingival blood flow are undefined. The autonomic nervous system response suggests that they could increase or decrease with exercise, and they may be independent of each other. This study attempts to answer these questions
Prospective comparison of F-18-PSMA-1007 PET/CT, whole-body MRI and CT in primary nodal staging of unfavourable intermediate- and high-risk prostate cancer
Purpose To prospectively compare F-18-prostate-specific membrane antigen (PSMA)-1007 positron emission tomography (PET)/CT, whole-body magnetic resonance imaging (WBMRI) including diffusion-weighted imaging (DWI) and standard computed tomography (CT), in primary nodal staging of prostate cancer (PCa). Methods Men with newly diagnosed unfavourable intermediate- or high-risk PCa prospectively underwent F-18-PSMA-1007 PET/CT, WBMRI with DWI and contrast-enhanced CT within a median of 8 days. Six readers (two for each modality) independently reported pelvic lymph nodes as malignant, equivocal or benign while blinded to the other imaging modalities. Sensitivity, specificity and accuracy were reported according to optimistic (equivocal lesions interpreted as benign) and pessimistic (equivocal lesions interpreted as malignant) analyses. The reference standard diagnosis was based on multidisciplinary consensus meetings where available histopathology, clinical and follow-up data were used. Results Seventy-nine patients completed all the imaging modalities, except for one case of interrupted WBMRI. Thirty-one (39%) patients had pelvic lymph node metastases, which were detected in 27/31 (87%), 14/31 (45%) and 8/31 (26%) patients by F-18-PSMA-1007 PET/CT, WBMRI with DWI and CT, respectively (optimistic analysis). In 8/31 (26%) patients, only F-18-PSMA-1007 PET/CT detected malignant lymph nodes, while the other two imaging modalities were reported as negative. At the patient level, sensitivity and specificity values for F-18-PSMA-1007 PET/CT, WBMRI with DWI and CT in optimistic analysis were 0.87 (95%CI 0.71-0.95) and 0.98 (95%CI 0.89-1.00), 0.37 (95%CI 0.22-0.55) and 0.98 (95%CI 0.89-1.00) and 0.26 (95%CI 0.14-0.43) and 1.00 (95%CI 0.93-1.00), respectively. Conclusion F-18-PSMA-1007 PET/CT showed significantly greater sensitivity in nodal staging of primary PCa than did WBMRI with DWI or CT, while maintaining high specificity.Peer reviewe
The challenge of preparing teams for the European robotics league: Emergency
© 2017, Society for Imaging Science and Technology. ERL Emergency is an outdoor multi-domain robotic competition inspired by the 2011 Fukushima accident. The ERL Emergency Challenge requires teams of land, underwater and flying robots to work together to survey the scene, collect environmental data, and identify critical hazards. To prepare teams for this multidisciplinary task a series of summer schools and workshops have been arranged. In this paper the challenges and hands-on results of bringing students and researchers collaborating successfully in unknown environments and in new research areas are explained. As a case study results from the euRathlon/SHERPA workshop 2015 in Oulu are given
Dynamic Operation of a Heat Exchanger in a Thermally Integrated Photovoltaic Electrolyzer
The outdoor operation of an up scaled thermally photovoltaic electrolyzer PV EC , constructed using a heat exchanger HE made of low cost materials, compared to its nonintegrated counterpart to quantify heat transfer and its effects, is studied. Thermal coupling of the PV and EC can reduce the difference between their temperatures, benefitting device performance. Such devices can produce hydrogen at rooftop installations of small to medium sized nonindustrial buildings. The devices are tested outdoors using automated real time monitoring. Under amp; 8776;880 amp; 8201;W amp; 8201;m amp; 8722;2 peak irradiance, they produced hydrogen at amp; 8776;120 and amp; 8776;110 amp; 8201;mL amp; 8201;min amp; 8722;1 rate with and without HE, respectively, corresponding to about 8.5 and 7.8 solar to hydrogen efficiencies. During about 700 amp; 8201;h of testing, the HE is beneficial at over amp; 8776;500 amp; 8201;W amp; 8201;m amp; 8722;2 due to cyclic device operation. Under lower irradiance levels, pumping previously heated electrolyte through the HE increases the PV and reduces the electrolyte temperature, reducing the device performance. The HE increases the cumulative hydrogen production amp; 8776;800 amp; 8201;L from both devices , so even relatively modest heat transfer rates can improve the PV EC operation. Improving the HE should further increase the benefits, but additional measures may be needed to maximize the hydrogen productio
A cross-sectional description of social capital in an international sample of persons living with HIV/AIDS (PLWH)
Background Social capital refers to the resources linked to having a strong social network. This concept plays into health outcomes among People Living with HIV/AIDS because, globally, this is a highly marginalized population. Case studies show that modifying social capital can lead to improvements in HIV transmission and management; however, there remains a lack of description or definition of social capital in international settings. The purpose of our paper was to describe the degree of social capital in an international sample of adults living with HIV/AIDS. Methods We recruited PLWH at 16 sites from five countries including Canada, China, Namibia, Thailand, and the United States. Participants (n = 1,963) completed a cross-sectional survey and data were collected between August, 2009 and December, 2010. Data analyses included descriptive statistics, factor analysis, and correlational analysis. Results Participant\u27s mean age was 45.2 years, most (69%) identified as male, African American/Black (39.9%), and unemployed (69.5%). Total mean social capital was 2.68 points, a higher than average total social capital score. Moderate correlations were observed between self-reported physical (r = 0.25) and psychological condition (r = 0.36), social support (r = 0.31), and total social capital. No relationships between mental health factors, including substance use, and social capital were detected. Conclusions This is the first report to describe levels of total social capital in an international sample of PLWH and to describe its relationship to self-reported health in this population
A Prospective Comparison of F-18-prostate-specific Membrane Antigen-1007 Positron Emission Tomography Computed Tomography, Whole-body 1.5 T Magnetic Resonance Imaging with Diffusion-weighted Imaging, and Single-photon Emission Computed Tomography/Computed Tomography with Traditional Imaging in Primary Distant Metastasis Staging of Prostate Cancer (PROSTAGE)
Background: Computed tomography (CT) and bone scintigraphy (BS) are the imaging modalities currently used for distant metastasis staging of prostate cancer (PCa). Objective: To compare standard staging modalities with newer and potentially more accurate imaging modalities. Design, setting, and participants: This prospective, single-centre trial (NCT03537391) enrolled 80 patients with newly diagnosed high-risk PCa (International Society of Urological Pathology grade group >= 3 and/or prostate-specific antigen [PSA] >= 20 and/or cT >= T3; March 2018-June 2019) to undergo primary metastasis staging with two standard and three advanced imaging modalities. Outcome measurements and statistical analysis: The participants underwent the following five imaging examinations within 2 wk of enrolment and without a prespecified sequence: BS, CT, Tc-99m-hydroxymethylene diphosphonate (Tc-99m-HMDP) single-photon emission computed tomography (SPECT)-CT, 1.5 T whole-body magnetic resonance imaging (WBMRI) using diffusion-weighted imaging, and F-18-prostate-specific membrane antigen-1007 (F-18-PSMA-1007) positron emission tomography(PET)-CT. Each modality was reviewed by two independent experts blinded to the results of the prior studies, who classified lesions as benign, equivocal, or malignant. Pessimistic and optimistic analyses were performed to resolve each equivocal diagnosis. The reference standard diagnosis was defined using all available information accrued during at least 12 mo of clinical follow-up. Patients with equivocal reference standard diagnoses underwent MRI and/or CT to search for the development of anatomical correspondence. PSMA PET-avid lesions without histopathological verification were rated to be malignant only if there was a corresponding anatomical finding suspicious for malignancy at the primary or follow-up imaging. Results and limitations: Seventy-nine men underwent all imaging modalities except for one case of interrupted MRI. The median interval per patient between the first and the last imaging study was 8 d (interquartile range [IQR]: 6-9). The mean age was 70 yr (standard deviation: 7) and median PSA 12 ng/mL (IQR:7-23). The median follow-up was 435 d (IQR: 378-557). Metastatic disease was detected in 20 (25%) patients. The imaging modality F-18-PSMA-1007 PET-CT had superior sensitivity and highest inter-reader agreement. The area under the receiver-operating characteristic curve (AUC) values for bone metastasis detection with PSMA PET-CT were 0.90 (95% confidence interval [CI]: 0.85-0.95) and 0.91 (95% CI: 0.87-0.96) for readers 1 and 2, respectively, while the AUC values for BS, CT, SPECT-CT, and WBMRI were 0.71 (95% CI: 0.58-0.84) and 0.8 (95% CI: 0.67-0.92), 0.53 (95% CI: 0.39-0.67) and 0.66 (95% CI: 0.54-0.77), 0.77 (95% CI: 0.65-0.89) and 0.75 (95% CI: 0.62-0.88), and 0.85 (95% CI: 0.74-0.96) and 0.67 (95% CI: 0.54-0.80), respectively, for the other four pairs of readers. The imaging method F-18-PSMA-1007 PET-CT detected metastatic disease in 11/20 patients in whom standard imaging was negative and influenced clinical decision making in 14/79 (18%) patients. In 12/79 cases, false positive bone disease was reported only by PSMA PET-CT. Limitations included a nonrandomised study setting and few histopathologically validated suspicious lesions. Conclusions: Despite the risk of false positive bone lesions, F-18-PSMA-1007 PET-CT outperformed all other imaging methods studied for the detection of primary distant metastasis in high-risk PCa. Patient summary: In this report, we compared the diagnostic performance of conventional and advanced imaging. It was found that F-18-prostate-specific membrane antigen-1007 positron emission tomography/computed tomography (F-18-PSMA-1007 PET-CT) was superior to the other imaging modalities studied for the detection of distant metastasis at the time of initial diagnosis of high-risk prostate cancer. PSMA PET-CT also appears to detect some nonmetastatic bone lesions. (C) 2020 The Author(s). Published by Elsevier B.V. on behalf of European Association of Urology.Peer reviewe
Increased Brain Fatty Acid Uptake in Metabolic Syndrome
OBJECTIVE: To test whether brain fatty acid uptake is enhanced in obese subjects with metabolic syndrome (MS) and whether weight reduction modifies it. RESEARCH DESIGN AND METHODS: We measured brain fatty acid uptake in a group of 23 patients with MS and 7 age-matched healthy control subjects during fasting conditions using positron emission tomography (PET) with [(11)C]-palmitate and [(18)F]fluoro-6-thia-heptadecanoic acid ([(18)F]-FTHA). Sixteen MS subjects were restudied after 6 weeks of very low calorie diet intervention. RESULTS: At baseline, brain global fatty acid uptake derived from [(18)F]-FTHA was 50% higher in patients with MS compared with control subjects. The mean percentage increment was 130% in the white matter, 47% in the gray matter, and uniform across brain regions. In the MS group, the nonoxidized fraction measured using [(11)C]-palmitate was 86% higher. Brain fatty acid uptake measured with [(18)F]-FTHA-PET was associated with age, fasting serum insulin, and homeostasis model assessment (HOMA) index. Both total and nonoxidized fractions of fatty acid uptake were associated with BMI. Rapid weight reduction decreased brain fatty acid uptake by 17%. CONCLUSIONS: To our knowledge, this is the first study on humans to observe enhanced brain fatty acid uptake in patients with MS. Both fatty acid uptake and accumulation appear to be increased in MS patients and reversed by weight reduction
Indiscriminate Males: Mating Behaviour of a Marine Snail Compromised by a Sexual Conflict?
Background: In promiscuous species, male fitness is expected to increase with repeated matings in an open-ended fashion (thereby increasing number of partners or probability of paternity) whereas female fitness should level out at some optimal number of copulations when direct and indirect benefits still outweigh the costs of courtship and copulation. After this fitness peak, additional copulations would incur female fitness costs and be under opposing selection. Hence, a sexual conflict over mating frequency may evolve in species where females are forced to engage in costly matings. Under such circumstance, if females could avoid male detection, significant fitness benefits from such avoidance strategies would be predicted. Methodology/Principal Findings: Among four Littorina species, one lives at very much higher densities and has a longer mating season than the other three species. Using video records of snail behaviour in a laboratory arena we show that males of the low-density species discriminate among male and female mucous trails, trailing females for copulations. In the high-density species, however, males fail to discriminate between male and female trails, not because males are unable to identify female trails (which we show using heterospecific females), but because females do not, as the other species, add a gender-specific cue to their trail. Conclusions/Significance: We conclude that there is likely a sexual conflict over mating frequency in the high-densit
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