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Background: The dysregulation of microRNAs (miRNAs) has been detected in patients with gastric cancer (GC), which inspired the use of miRNAs as a novel biomarker for GC. In this study, we investigated the previously reported miRNA dysfunction in cancer tissues as a potential plasma biomarker for GC using quantitative reverse transcriptase polymerase chain reaction (RT-PCR). Methods: The published miRNA abnormalities were searched in the microRNA Cancer Association Database. Plasma samples were collected from patients with GC (n = 26) and controls (n = 17). The sensitivity and specificity of polyadenylation RT-PCR (PA-RT) and stem-loop RT-PCR (SL-RT) were compared. Statistical comparisons between patients with GC and controls were performed to identify miRNA biomarkers, and correlation analyses between the threshold cycle (Ct) values of miRNAs and various blood biochemical parameters were performed to elucidate the confounding factors. Results: mir-17, mir-21, mir-31, mir-99b, mir-222, and U6 were selected. PA-RT showed greater sensitivity and lower specificity than SL-RT (PA-RT vs. SL-RT, mean Ct: 19.6 vs. 29.2; coefficient of variation: 0.42 vs. 0.10). Adopting SL-RT owing to its higher specificity, only mir-222 was significantly upregulated in patients with GC (GC vs. control, miRNA expression: 15.4 vs. 5.27, p = 0.0098). Regarding the correlation between blood biochemical parameters and cells with miRNA expression, mir-31 and mir-99b were correlated with blood urea nitrogen, mir-17, mir-21, and mir-99b were negatively correlated with platelets, and mir-21 was correlated with neutrophils. No obvious correlations were noted between mir-222 expression and blood parameters. Receiver operating characteristic (ROC) curve analysis indicated that mir-222 identified GC patients with a maximum area under the curve (0.73, 95% confidence interval 0.57–0.89). Conclusions: Plasma mir-222 was confirmed to be dysregulated in patients with GC, irrespective of blood biochemical parameters. [ABSTRACT FROM AUTHOR]

Not much is known about the changes in bone density due to fish reproductive migration. We used micro-CT and inferential statistics to determine whether the relative bone density in the skulls of adult Three-lips fish, that seasonally upstream migrated to a Lake Biwa tributary, changed across their known reproductive season. The relative bone density significantly decreased as standard length and condition factor (K) increased in both sexes. This negative relationship is likely due to age and hormonal effects in the fish. Results from the bone density analysis also revealed that male Three-lips fish had potentially lower relative bone density (although not significantly different) than females during peak reproductive migration, i.e., July to August. On average, male Three-lips fish are larger in length and weight than females, and in many species, females prefer larger males to smaller males, viewing their size as an indicator of genetic fitness and their ability to provide protection. Resources in the skulls of Three-lips males may be distributed in such a way that increases reproductive success, i.e., size at the expense of quality. In addition, individuals with slightly less dense bones, particularly males, appeared later than those with denser bones during the peak of the reproductive season. The high energy demands involved with aggression in males, often requires resource mobilization from various tissue compartments and could explain the slightly lower density in the latter half of the peak migration. Furthermore, Three-lips individuals that migrated earlier and later during the reproductive season may have more energy reserves than those that had been in the river for some time, hence the variable bone density between individuals. This study serves as a foundation for future studies on the effects of migration, changes in physiology and age on bone density analysis of Three-lips fish and other species in various ecosystems. [ABSTRACT FROM AUTHOR]

The changing climate makes it more difficult to manage water resources and food production sustainably. Various adaptation measures have been proposed to moderate the negative impacts of climate change; however, implementation of these measures may be hampered by other factors even if the benefits are acknowledged—a situation termed "soft adaptation limits" by the IPCC. We hypothesized that societal rules can be a potential barrier to adaptive action if they are too fixed, because such rules have coevolved with the interactions between the past climate and human activities. To test this hypothesis, we present a framework based on the assumption that associated societal rules of Japan's matured irrigation systems are potential barriers to adaptation. The framework consisted of two process‐based models, one to evaluate the water deficit risk and one to evaluate the benefits of optimizing rice yield and quality. We applied each model to an experiment in which we shifted the current transplantation date by 1 week for up to 5 weeks before and after the current date under the historical (1981–2000) and RCP 2.6 and 8.5 (2011–2030 and 2031–2050) scenarios. We revealed two contrasting development pathways in the study watershed. Soft adaptation limits imposed by water availability will occur by 2030 if farmers optimize for quality, whereas mutual benefits to farmers and river administrators will be achieved if farmers seek yield. We argue that more participatory research with stakeholder engagement, as well as policy discussions about these possible developments, is needed to ensure successful adaptation. Key Points: We present a framework for examining whether societal rules of Japan's matured irrigation systems are potential barriers to adaptationWe show that potential barriers to adaptation imposed by water availability will occur if farmers optimize for rice qualityWe argue that more participatory research with stakeholder engagement is needed to ensure successful adaptation [ABSTRACT FROM AUTHOR]

Most pest phenology models are temperature dependent. Generally, the air temperature at reference height is used to predict pest development, but the air temperature varies between inside and outside the crop canopy, where pests reside. Here, we sampled 3 rice planthopper species—Nilaparvata lugens (Stål), Sogatella furcifera (Horváth), and Laodelphax striatellus (Fallén)—and micrometeorological observations in paddy fields to analyze how thermal environments inside the canopy affect pest development. Seasonal variations in the population density of these species were surveyed in 3 experimental fields with 2 water temperature plots (normal and low-water temperature plots).The development periods of the 3 species were predicted individually based on pest phenology models using temperatures recorded at 6 heights (0.0–2.0 m). We calculated the root mean square error (RMSE) values from the predicted and observed development periods for each rice planthopper. The development prediction using the temperature inside the canopy was more accurate than that utilizing the temperature at the reference height (2.0 m). In the low-water temperature plot, the RMSE value for N. lugens, S. furcifera, and L. striatellus was 6.4, 5.6, and 4.1 when using the temperature at the reference height (2.0 m), respectively, and 2.8, 3.8, and 2.9 when employing the temperature inside the canopy at 0.25 m, respectively. The development prediction utilizing the air temperature at the bottom (0.25 m) of canopy, where N. lugens resides, was most effective for N. lugens among the 3 species. These findings suggest the importance of utilizing microhabitat-based temperatures to predict pest development. [ABSTRACT FROM AUTHOR]

We present an alternative method to determine leaf CO2 assimilation rate (An), eliminating the need for gas exchange measurements in proximal and remote sensing. This method combines the Farquhar–von Caemmerer–Berry photosynthesis model with mechanistic light reaction (MLR) theory and leaf energy balance (EB) analysis. The MLR theory estimates the actual electron transport rate (J) by leveraging chlorophyll fluorescence via pulse amplitude‐modulated fluorometry for proximal sensing or sun‐induced chlorophyll fluorescence measurements for remote sensing, along with spectral reflectance. The EB equation is used to directly estimate stomatal conductance from leaf temperature. In wheat and soybean, the MLR‐EB model successfully estimated An variations, including midday depression, under various environmental and phenological conditions. Sensitivity analysis revealed that the leaf boundary layer conductance (gb) played an equal, if not more, crucial role compared to the variables for J. This was primarily caused by the indirect influence of gb through the EB equation rather than its direct impact on convective CO2 exchange on the leaf. Although the MLR‐EB model requires an accurate estimation of gb, it can potentially reduce uncertainties and enhance applicability in photosynthesis assessment when gas exchange measurements are unavailable. Summary statement: This study introduces a novel model for high‐throughput estimation of leaf CO2 assimilation rate. By combining the Farquhar–von Caemmerer–Berry biochemical model with mechanistic light reaction theory and the leaf energy balance equation, this model eliminates the need for parameterisation using gas exchange measurements. [ABSTRACT FROM AUTHOR]

Migration is vital for the continuation of a species. In this study, we explored migration hotspots of the vulnerable Hasu fish in Lake Biwa tributaries using two complementary methods: environmental DNA (eDNA) and visual counts. The study encompassed the known range of Hasu around Lake Biwa tributaries during its reproductive season. Monthly water sampling and visual inspection was conducted, from May to September, in 32 Class A tributaries—at the river mouth and within the river channel. Hasu eDNA was extracted from water samples and quantified using real‐time polymerase chain reaction. Environmental factors were also assessed on‐site, and their effects on eDNA and visual count trends evaluated using linear models and Akaike information criterion. eDNA was detected at sites where the fish were both observed and not observed. A zero‐hurdle model revealed positive correlation between eDNA copies and visual counts of migrating Hasu, with pH having a reducing effect on the relationship (p < 0.05). Analysis of Hasu eDNA copies and visual count trends, with environmental factors as explanatory variables, indicates that Hasu is likely to be found in rivers that are wide and deep enough to accommodate migrating individuals, have fast‐flowing currents, and sandy‐gravel substrates during reproductive migration. Such rivers are mostly located on the western side of the northern basin and include the Ado, Chinai, and Shiotsuo Rivers. These could be considered as Hasu migration hotspots and require protecting if the population of Hasu in Lake Biwa is to be recovered. [ABSTRACT FROM AUTHOR]