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The aim of this study was to evaluate the hypothesis that cerebral hemoglobin (Hb) oxygenation is related to phosphorylation potential during primary and secondary cerebral energy failure in newborn infants who have experienced birth asphyxia. We subjected newborn piglets to severe transient cerebral hypoxic-ischemia followed by resuscitation and examined cerebral energy metabolism by 31P-magnetic resonance spectroscopy and evaluated changes in cerebral Hb oxygen saturation (ScO2) using full-spectrum near-infrared spectroscopy before, during, and up to 54 h after the hypoxic-ischemic insult. ScO2 was significantly decreased during the hypoxic-ischemic insult compared with baseline values. During secondary energy failure, piglets were separated based on the relationship between the ratio of phosphocreatine to inorganic phosphate and ScO2; those with a negative correlation were less injured than those with a positive correlation. These results indicate that changes in ScO2 as measured by near-infrared spectroscopy are related to phosphorylation potential during secondary energy failure in asphyxiated infants.

We evaluated the applicability of the Australian Weed Risk Assessment (AWRA) system in Japan. Native weeds (n = 117) and introduced plants (n = 142), whose weed status was classified by 20 plant experts, were assessed using a slightly modified version of the AWRA system designed to fit Japanese conditions. A receiver operating characteristic (ROC) curve for the system, when classifying two-thirds of the 259 taxa as weeds or non-weeds, was plotted and the area under the ROC curve was calculated. The area was 0.88 and significantly greater than 0.5. Thus, the validity of the system to classify plants was proven. The best cut-off level for the WRA score using Youden’s index was 10. When taxa whose AWRA scores were greater than 10 were regarded as weeds, the sensitivity and specificity were 0.88 and 0.78, respectively. These values were verified with the remaining one-third of the taxa. From these findings, the modified AWRA system was considered to be effective for use in Japan. However, further studies are required to set the best cut-off level in terms of maximising the benefits gained from using the system. A second screening test associated with the cut-off level also needs to be developed.