Caveats and Recommendations to Assess the Validity and Reliability of Cycling Power Meters: A Systematic Scoping Review

A large number of power meters have become commercially available during the last decades to provide power output (PO) measurement. Some of these power meters were evaluated for validity in the literature. This study aimed to perform a review of the available literature on the validity of cycling power meters. PubMed, SPORTDiscus, and Google Scholar have been explored with PRISMA methodology. A total of 74 studies have been extracted for the reviewing process. Validity is a general quality of the measurement determined by the assessment of different metrological properties: Accuracy, sensitivity, repeatability, reproducibility, and robustness. Accuracy was most often studied from the metrological property (74 studies). Reproducibility was the second most studied (40 studies) property. Finally, repeatability, sensitivity, and robustness were considerably less studied with only 7, 5, and 5 studies, respectively. The SRM power meter is the most used as a gold standard in the studies. Moreover, the number of participants was very different among them, from 0 (when using a calibration rig) to 56 participants. The PO tested was up to 1700 W, whereas the pedalling cadence ranged between 40 and 180 rpm, including submaximal and maximal exercises. Other exercise conditions were tested, such as torque, position, temperature, and vibrations. This review provides some caveats and recommendations when testing the validity of a cycling power meter, including all of the metrological properties (accuracy, sensitivity, repeatability, reproducibility, and robustness) and some exercise conditions (PO range, sprint, pedalling cadence, torque, position, participant, temperature, vibration, and field test).

Comparative Metabolomics Analysis of Citrus Varieties

Many citrus varieties are hybridized to improve their quality and to overcome the effects of climate change. However, there is limited information on the effect of the chemical profiles of hybrid varieties on their quality. In this study, we analyzed 10 citrus varieties and evaluated the correlation with their general characteristics and antioxidant activities. Chemical profiles, including the contents of sugars, organic acid compounds, flavonoids, limonoids, and carotenoids, which are related to taste, color, and health benefits, were significantly different depending on the citrus varieties, leading to different antioxidant capacities and general quality parameters. Based on these data, the correlations were investigated, and 10 citrus varieties were clustered into four groups—Changshou kumquat and Jeramon (cluster I); Setoka (cluster II-1); Natsumi, Satsuma mandarin, and Navel orange (cluster Ⅱ-2); Kanpei, Tamnaneunbong, Saybyeolbong, and Shiranui (cluster II-3). Moreover, a metabolomic pathway was proposed. Although citrus peels were not analyzed and the sensory and functional qualities of the citrus varieties were not investigated in this study, our results are useful to better understand the relationship between citrus quality and metabolite profiles, which can provide basic information for the development and improvement of new citrus varieties.

Spatial Variation and Terrain Gradient Effect of Ecosystem Services in Heihe River Basin over the Past 20 Years

With the advent of large-scale development, extreme imbalance in the ecology of the Heihe River Basin (HRB) has caused a series of ecological problems. In order to explore the spatiotemporal variation of ecosystem services (ESs) and to assess the characteristics of ESs under the terrain gradient effect (TGE), the three key ESs were quantified based on the InVEST model using five series of land-use data obtained from remote sensing images from 2000 to 2020 in this study. The terrain index was used to analyze the influence of terrain on ESs. The results show that most of the ESs were in high numbers in the south and low numbers in the north, as well as high numbers in the middle and upper reaches and low numbers at downstream locations. It was found that high-quality habitats degrade to general-quality habitats, and poor-quality habitats evolve into general-quality habitats. It was also found that the water production volume continues to decline and soil conservation becomes relatively stable with little change. This study illustrates different ESs showing obvious TGE with changes in elevation and slope. These results indicate that the effect of land-use change is remarkable and TGE is highly important to ESs in inland watersheds. This research study can provide a scientific basis for the optimization of regional ecosystem patterns. The results are of great significance in terms of rational planning land use, constructing ecological civilizations, and maintaining the physical conditions of land cover at inland river basins.

Bipolar Androgen Therapy in the management of prostate cancer

Introduction and purpose: Prostate cancer (PCa) as one of the most frequent neoplasms in men remains a challenge for oncologists. The main strategy of its treatment is the Androgen Deprivation Therapy (ADT) the principle of which is an inducement of hypogonadism. The lack of testosterone is not only a factor greatly contributing to a decrease of quality of life overall, but additionally it increases the odds of the complications, including low libido and erectile disfunction, metabolic abnormalities, high cardiovascular risk, osteoporosis, anaemia, or depression. ADT also has the potential of inducement of castration resistance (CRPC), which significantly worsen patients prognosis. The main purpose of this review is to explore the Bipolar Androgen Therapy (BAT), which has the potential to solve the aforementioned problems. State of knowledge: The mechanism of BAT action has been described. BAT is effective not only against CRPC, but androgen-dependant PCa as well. BAT reverses the hormone resistance in CRPC, thus allowing the rechallenging of the ADT. It has the direct cytotoxic effect on cancer cells. Additionally BAT increases the exponents of the general quality of life of the patients. There is a number of active clinical trials regarding BAT. Conclusions: BAT is a safe therapeutic strategy with the high efficacy in reversing hormone resistance in CRPC patients, thus significantly increasing their health prognoses and it allows to alleviate or avoid the adverse effects of ADT.

Science Needs Systematic Replicability Audits

The credibility revolution in social science has highlighted the importance of conducting replication studies. Despite this growing awareness, the value of direct replications is still hotly debated. In this article, we identify three main functions served by replication. We argue that replications are valuable when they target important or influential studies, when they provide a general estimate of the replicability rate of a population of published articles, and when they create incentives favoring replicable research. We therefore argue that the scientific community should organize systematic large-scale replication audits of two subsets of journals’ published articles: a subset of the most-cited articles, and a subset of randomly selected articles that would provide an estimate of the replicability of the journals' articles. These replicability audits should pave the way for more general quality audits of scientific journals.

Accuracy and Reliability of Internet Resources for Information on Monoclonal Gammopathy of Undetermined Significance—What Information Is out There for Our Patients?

Background: Online information gathering can increase patients’ engagement in decision-making. The quality of online resources available for monoclonal gammopathy of undetermined significance (MGUS) was evaluated. Methods: 900 websites from Google, Bing, Yahoo, and 150 YouTube videos were assessed. Results: The websites did not differ regarding their search rank or between the search engines. The median time since last update was 24 months. The 86 unique websites showed a medium to poor general quality (JAMA score 3/4, only 8.1% websites with a valid HON certificate). The patient- (user-) focused quality was poor (sum DISCERN score 27/80 points). The reading level was difficult (11th US school grade). The content level was very low (13/50 points). 12.8% of websites contained misleading/wrong facts. Websites provided by scientific/governmental organizations had a higher content level. For the 61 unique videos, the median time since upload was 34 months. The videos showed a medium general quality (HON Foundation score). The patient- (user-) focused quality was poor (sum DISCERN score 24 points). The content level was very low (6 points). Conclusion: MGUS-relevant online sources showed a low quality that was provided on a high reading level. Incorporation of quality indices and regular review of online content is warranted.

AN INTERCOMPARISON PROJECT ON 14C FROM SINGLE-YEAR TREE RINGS

ABSTRACT A laboratory intercomparison project was carried out on 20 annually resolved late-wood samples from the Danish oak record. The project included the following three laboratories: (1) the University of Arizona AMS Laboratory, University of Arizona, USA (AA); (2) HEKAL AMS Laboratory, MTA Atomki, Hungary (DeA); and (3) Aarhus AMS Centre (AARAMS), Aarhus University, Denmark (AAR). The large majority of individual data points (96%) lie within ±2σ of the weighted mean. Further assessment of the accuracy associated with the individual laboratories showed good agreement, indicating that consistent and reliable 14C measurements well in agreement with each other are produced at the three laboratories. However, the quoted analytical uncertainties appear to be underestimated when compared to the observed variance of differences from the geometric mean of the samples. This study provides a general quality check of the single-year tree-ring 14C measurements that are included in the new calibration curve.

Optimization of cone beam computed tomography for the assessment of alterations of the maxillary sinuses

Objective: To test the standard protocols of a CBCT unit in order to find lower-dose alternatives with diagnostically acceptable image quality for the maxillary sinuses visualization. Study design: An observational study was performed. Two dry skulls were used to simulate four conditions of the maxillary sinuses: normality, mucous retention pseudocyst, membrane thickening and bone graft. Cone beam computed tomography scans were obtained with an i-CAT classic unit using different acquisition protocols and a box of polystyrene to simulate soft tissue attenuation. All the protocols were established by the manufacturer, combining different energy parameters, fields of view and voxel sizes. Multiplanar reconstructions were presented to three Oral Radiologists through blind and randomized distribution. The specialists judged general image quality, sharpness, contrast, and the presence of noise and artifacts based on a 4-points scale. Results: Protocols with higher energy parameters had significant association with higher scores for general quality, sharpness and contrast (p<0.05). Protocols with intermediate level of radiation dose had also significant association with good and excellent image quality; for the presence of noise and artifacts the images were rated acceptable. Conclusion: i-CAT default protocols with lower dose of radiation were able to deliver acceptable image quality for the visualization of the maxillary sinuses.