Core Ideas Paddy soil shrinkage behaviors and cracking patterns were significantly influenced by wetting and drying cycles. Wetting and drying (WD) intensity had a greater impact on soil shrinkage than WD frequency and sequence. The crack area can be better predicted by shrinkage curve when considering wetting and drying cycles. The geometry factor is linked to soil shrinkage and cracking. Linking soil shrinkage and cracking Soil cracks develop in paddy soils during wetting and drying (WD) cycles. Although changes in soil structure related to cracking have often been described as soil shrinkage, the relationship between soil shrinkage and cracking remains unclear. The objectives of this study were to investigate how WD cycles affect soil shrinkage and cracking and to establish a link between soil shrinkage in the laboratory and cracking in the field. Two paddy fields (one young paddy field and one old paddy field) were subjected to multiple WD cycles during rice growth. Soil cracks were photographed in the field, and the area density ( D c ), compactness of cracks (CP), and equivalent width (EW) of the cracks were analyzed. The shrinkage curves of soil cores that were sampled in the two paddy fields were determined after they were subjected to various laboratory‐based simulated WD cycles (including variations in intensity, frequency, and sequence). To estimate soil cracking, three parameterizations based on the shrinkage curves of the soil cores treated with non‐predrying (Parameterization A), slight drying (Parameterization B), and intense drying (Parameterization C) were established. The YPF soil presented greater D c and CP than the OPF soil (P < 0.05), whereas the OPF soil exhibited greater EW and coefficient of linear extensibility (P < 0.05). Area density was not only affected by the current soil water content or by the previous drying history. As the number of WD cycles increased, equivalent width generally increased, whereas CP decreased. The intensity of the WD cycles affected shrinkage more than the frequency or sequence. The fitted geometry factor, r s , decreased from Parameterization A to Parameterization C for both soils. The D c values were more accurately estimated by using soil shrinkage curves that included the intensity of the WD cycles. Our results demonstrate that the soil shrinkage curve associated with r s can better predict cracking when the effects of WD cycles are considered.
For objective evaluation of the efficacy and safety of ceftazidime (CAZ), a new cephem antibiotic, in respiratory tract infections, a double blind comparative study was carried out against cefotiam (CTM). Either of the drugs was administered by intravenous drip infusion in the unit dose of 1 g (potency) twice daily for 14 days, and the following results were obtained.1. In the assessment by the efficacy Assessment Committee, the overall clinical efficacy rate was 73.2%(90/123) in the CAZ group and 72.0%(90/125) in the CTM group, with no statistically significant difference between the two treatments. When reviewed for each diagnosis, the efficacy rate was slightly lower in the CAZ group than that in the CTM group 60.6%(40/66) and 74.2%(49/66), respectively, in bacterial pneumonia and lung abscess, although there was no significant difference between the two treatments. Whereas in chronic RTI the efficacy rate was higher in the CAZ group (86.0%, 43/50) than that in the CTM group (66.7%, 36/54) with significant difference (χ2-test, <0.05).2. In the assessment by the physicians in charge, the overall clinical efficacy rate for all cases was 70.7%(104/147) in the CAZ group and 63.7%(101/147) in the CTM group, with no significant difference between the two treatments. When reviewed for each diagnosis, efficacy rate was 70.1%(68/97) in the CAZ group and 71.7%(66/92) in the CTM group in the treatment of bacterial pneumonia and lung abscess, and there was statistically no significant difference between the two treatments. In chronic RTI, the efficacy rate in the CAZ group (79.5%, 35/44) tended to be higher than that in the CTM group (66.7%, 34/51) (U-test, p<0.10).3. In the 112 cases (55 cases in the CAZ group, 57 cases in the CTM group) in which the bacteriological response could be assessed, elimination of bacteria was achieved in more cases in the CAZ group than in the CTM group, with significant difference (U-test, χ2-test, p<0.01). As to the eradication rate including “replaced”, there was no statistically significant difference between the two treatments.4. As far as the incidence of side effects and abnormal laboratory findings were concerned, there was no significant difference between the two treatments.5. The Committee assessed the overall utility (efficacy + safety) as 84.0%(42/50) in the CAZ groupand 66.7%(36/54) in the CTM group in chronic RTI, and the utility in the CAZ group tended to be higher than that in the CTM group (χ2-test, p<0.10). In other diagnoses and also in all cases, there was no significant difference between the two treatments. In the assessment by the physicians in charge, there was no significant difference between the two drugs in the utility.From the above results, CAZ was considered to be as useful as CTM, based on the efficacy and safety in respiratory tract infections.
Abstract Cesium in soil exists in two forms. The soil in Fukushima Prefecture contaminated with radioactive cesium was classified into two fractions: the fraction of cesium with weak adsorption to soil (F 1 ), and the fraction of cesium with strong adsorption to soil (F 2 ). We evaluated the absorption of Cs by different crops (rice, soybean, and buckwheat) in different soil fractions by measuring the 133 Cs and 137 Cs concentrations in the soil and crops. We also evaluated the effect of potassium fertilization on cesium suppression in different soil fractions. Without K fertilization, 137 Cs was absorbed mostly from the F 1 fraction by all three crops; 133 Cs was absorbed mostly from the F 2 and F 1 fractions by soybean and buckwheat, respectively, and from both F 1 and F 2 fractions by rice. Potassium fertilization decreased the percentages of both 137 Cs and 133 Cs absorbed from the F 2 fraction by soybean. In contrast, buckwheat presented reduced absorption from the F 1 fraction. In rice, the uptake of cesium by fraction did not change with or without potassium fertilization, indicating that different crops absorb cesium from different soil fractions.
