Evaluation of belowground seasonal dynamics of Typha angustifolia after cutting treatment

Typha angustifolia, an emergent macrophyte, shows different growth characteristics under the influence of external forces. In this study, the growth characteristics of T, angustifolia were investigated after cutting the shoots (treatment area: 3m×4m). The treatment is considered as an external force. Two stands, one in a sterile zone and the other in a fertile zone, were cut at the end of June 2001 and the subsequent re-growth characteristics were observed. The difference of response, after cutting their shoots in the fertile zone and sterile zone was prominent. Shoot re-growth model was developed to evaluate the belowground dynamics by calibrating the choot height and aboveground parameters. The belowground biomass of cut area after one year was simulated to be about 80% of that of uncut area. The results were verified using the belowground biomass observed in April 2002. The buds in the cut area are shorter than those of the uncut area. Morever, the cut area in the ferile zone generated thinner buds than that of the sterile zone. The belowground biomass and re-growth strategy after cutting were supposed to cause the differences of their buds the year after.Article信州大学山地水環境教育研究センター研究報告 2: 29-34(2004)departmental bulletin pape

Investigation of ship waves in a narrow channel

This paper presents a discussion of the characteristics of ship waves in a narrow channel restricted by vertical walls, based on observed data and the results computed by a 2-D model. In the numerical model, the propagation of waves generated by a moving ship is simulated by solving 2-D depth-integrated Boussinesq equations. To get the boundary conditions at the location of the ship, the slender-ship approximation is employed. A field observation was carried out at a straight length of navigation channel. The ships targeted in the observations are two kinds of waterbuses with lengths of 28 and 24 m. The relative depth Froude number for the river current, an appropriate parameter for assessing the influence of the current on ship wave characteristics in a navigation channel, ranged from 0.47 to 0.76. The observed maximum wave height varied between 0.13 and 1.26 m. The maximum wave height of the wave train is sharply increased when the relative depth Froude number exceeds 0.6. The results computed by the present model agree fairly well with the observed data

The possibility of mutations of RAS signaling genes and/or TP53 in combination as a negative prognostic impact on pathological stage I non‐small cell lung cancer

Abstract Background The recurrence rate of non‐small cell lung cancer (NSCLC) is as high as 30%, even in the cancer with pathological stage I disease. Therefore, identifying factors predictive of high‐risk pathological recurrence is important. However, few studies have examined the genetic status of these tumors and its relationship to prognosis. Materials and Methods A cohort of 328 cases of primary lung cancer that underwent complete resection at Tokyo Medical and Dental University (TMDU) was screened for 440 cancer‐associated genes using panel testing. Further analyses included 92 cases of pathological stage I NSCLC who did not receive adjuvant chemotherapy. Ridge regression was performed to identify association studies mutational status and postoperative recurrence. These data were then validated using clinical and genetic data from 56 patients in The Cancer Genome Atlas (TCGA). Results Mutations in TP53, RAS signaling genes KRAS and HRAS, and EGFR were recurrently detected. Ridge regression analysis relevant to recurrence, as well as survival analysis, performed using data from the TMDU cohort revealed significantly shorter relapse‐free survival (RFS) for patients with RAS signaling or TP53 gene mutations than for those without (log‐rank test, p = 0.00090). This statistical trend was also suggested in the TCGA cohort (log‐rank test, p = 0.10). Conclusion Mutations in RAS signaling genes and/or TP53 could be useful for the prediction of shorter RFS of patients with stage I NSCLC

Viral load of SARS‐CoV‐2 Omicron BA.5 is lower than that of BA.2 despite the higher infectivity of BA.5

Abstract Background Sublineage BA.5 of the SARS‐CoV‐2 Omicron variant rapidly spread and replaced BA.2 in July 2022 in Tokyo. A high viral load can be a possible cause of high transmissibility. Methods and Results The copy numbers of SARS‐CoV‐2 in nasopharyngeal swab samples obtained from all patients visiting the hospital where this research was conducted were measured using reverse transcription‐quantitative polymerase chain reaction (RT‐qPCR). Viral genotypes were determined using PCR‐based melting curve analysis. Next, whole‐genome sequencing was performed using approximately one fifth of the samples to verify the viral genotypes determined using PCR. Then, the copy numbers of the BA.1, BA.2, and BA.5 cases were compared. Contrary to expectations, the copy numbers of the BA.5 cases (median 4.7 × 104 copies/μL, n = 291) were significantly (p = .001) lower than those of BA.2 cases (median 1.1 × 105 copies/μL, n = 184). There was no significant difference (p = .44) between the BA.5 and BA.1 cases (median, 3.3 × 104 copies/μL; n = 215). Conclusion: The results presented here suggest that the increased infectivity of BA.5 is not caused by higher viral loads, but presumably by other factors such as increased affinity to human cell receptors or immune escape due to its L452R mutation