23 research outputs found
Fate of Iprobenfos and Tricyclazole at Paddy Cultivation Environment
Objectives This study aimed to identify the fate of iprobenfos and tricyclazole in the soil and paddy water during the rice cultivation process and to identify their exposure pathways into surface water. Methods Both iprobenfos and tricyclazole were sprayed onto two sample sites following the pesticide safety usage guidelines. Residues in the samples. Soil, paddy water, and drainage water samples were collected for 28 days after post-application. Residues were subsequently analyzed using LC-MS/MS. Results and Discussion The fate of the two pesticides, iprobenfos and tricyclazole, in the rice cultivation environment was influenced by factors such as soil half-life, Koc, water solubility, formulation, and precipitation patterns. Initial concentrations of iprobenfos and tricyclazole in the paddy field near the drainage were 5,774 μg/L and 307 μg/L, respectively, while concentrations in the drain water were 1,850 μg/L and 182 μg/L. Four days after application, the residual concentrations of iprobenfos and tricyclazole in both paddy and drain water ranged from N.D. (Not Detected) to 5.6 μg/L and N.D. to 56 μg/L, respectively, indicating a rapid decline. During the experimental period, the average concentration reduction ratios in drain water near the drainage compared to the drain water were higher for tricyclazole (90%) than for iprobenfos (52%). Conclusion The soil and water half-life of tricyclazole exceeded that of iprobenfos, leading to a slower rate of concentration reduction. The lower Koc value for tricyclazole suggests enhanced soil desorption due to rainfall, increasing its concentration in paddy fields. The presence of iprobenfos and tricyclazole in surface water is likely due to dispersion during pesticide application. While concentrations diminish owing to the dilution effect when water moves from paddy fields to surface water, it's posited that runoff could affect nearby stream water within seven days post-application
Hanja alexia with agraphia after left posterior inferior temporal lobe infarction: a case study.
Korean written language is composed of ideogram (Hanja) and phonogram (Hangul), as Japanese consists of Kanji (ideogram) and Kana (phonogram). Dissociation between ideogram and phonogram impairment after brain injury has been reported in Japanese, but few in Korean. We report a 64-yr-old right-handed man who showed alexia with agraphia in Hanja but preserved Hangul reading and writing after a left posterior inferior temporal lobe infarction. Interestingly, the patient was an expert in Hanja; he had been a Hanja calligrapher over 40 yr. However, when presented with 65 basic Chinese letters that are taught in elementary school, his responses were slow both in reading (6.3 sec/letter) and writing (8.8 sec/letter). The rate of correct response was 81.5% (53 out of 65 letters) both in reading and writing. The patient's performances were beyond mean-2SD of those of six age-, sex-, and education-matched controls who correctly read 64.7 out of 65 and wrote 62.5 out of 65 letters with a much shorter reaction time (1.3 sec/letter for reading and 4.0 sec/letter for writing). These findings support the notion that ideogram and phonogram can be mediated in different brain regions and Hanja alexia with agraphia in Korean patients can be associated with a left posterior inferior temporal lesion
Abstract Word Definition in Patients with Amnestic Mild Cognitive Impairment
The aims of this study were to investigate concrete and abstract word definition ability (1) between patients with amnestic mild cognitive impairment (aMCI) and normal adults and (2) between the aMCI subtypes (i.e., amnestic single-domain MCI and amnestic multidomain MCI; asMCI and amMCI) and normal controls. The 68 patients with aMCI (29 asMCI and 39 amMCI) and 93 age- and education-matched normal adults performed word definition tasks composed of five concrete (e.g., train) and five abstract nouns (e.g., jealousy). Task performances were analyzed on total score, number of core meanings, and number of supplementary meanings. The results were as follows. First, the aMCI patients scored significantly poorer than the normal controls in only abstract word definition. Second, both subtypes of aMCI performed worse than the controls in only abstract word definition. In conclusion, a definition task of abstract rather than concrete concepts may provide richer information to show semantic impairment of aMCI
Intransigent Vowel-Consonant Position in Korean Dysgraphia: Evidence of Spatial-Constructive Representation
Dysgraphia due to a focal brain lesion can be characterized by substitution, transposition, deletion and/or addition errors of graphemes or strokes. However, those linguistic errors can be language-specific because the writing system of a given language may influence error patterns. We investigated a Korean stroke patient, a 57-year-old English teacher with dysgraphia both in Korean Han-geul (한글) and in English alphabet writings. The results of an experimental testing revealed transposition errors between a consonant and a vowel only in English but not in Korean writings. This austerity of vowel-consonant position may be attributed to a unique Korean writing system of a spatially well-formed syllabic configuration or block with consonant(s) and a vowel. In light of a neuropsychological model of writing, which depicts a multi-level spelling and writing process, we suggest a spatial-constructional component of internal orthographic representations in Korean writing. This Korean graphemic configuration feature may be resistant to a focal, left cerebral damage, and thus, we also discuss our results in terms of cerebral lateralization of the writing processes
Evaluation of chewing ability in cerebrovascular accident and Parkinson’s disease
Purpose: Chewing problems are a major and prevalent issue in populations with neurological pathologies including cerebrovascular accident (CVA) and Parkinson’s disease (PD). We measured habitual solid chewing performance in patients with CVA or PD and compared it to that of normal older adults to identify differences in chewing ability between groups.Methods: Measures of habitual solid chewing in 32 patients with CVA, in 35 patients with PD, and in 217 normal older adults were compared. Data on the chewing duration, frequency, and rate were collected using a solid chewing task (SCT). We also analyzed the relationships between dentures, number of teeth, and SCT outcomes.Results: The chewing duration in the PD group was significantly longer than the normal group (p<0.05). Chewing frequency and rate were not significantly different among the three groups. Results can be explained by rigidity and bradykinesia in orofacial structures in the PD group. No significant differences between the PD and CVA groups may be partly explained by the diverse location and size of the CVA lesion compared to the PD. Dentures and the number of teeth were not significantly correlated with SCT outcomes.Conclusions: Chewing impairment remains the area of development for research and rehabilitation, and SCT may help to assess oropharyngeal dysphagia and to identify therapeutic interventions.11Nscopu
Effects of frontal-executive dysfunction on self-perceived hearing handicap in the elderly with mild cognitive impairment.
It is increasingly agreed upon that cognitive and audiological factors are associated with self-perceived hearing handicap in old adults. This study aimed to compare self-perceived hearing handicap among mild cognitive impairment (MCI) subgroups and a cognitively normal elderly (CNE) group and determine which factors (i.e., demographic, audiometric, or neuropsychological factors) are correlated with self-perceived hearing handicap in each group. A total of 46 MCI patients and 39 hearing threshold-matched CNE subjects participated in this study, and their age ranged from 55 to 80 years. The MCI patients were reclassified into two groups: 16 with frontal-executive dysfunction (FED) and 30 without FED. All subjects underwent audiometric, neuropsychological, and self-perceived hearing handicap assessments. The Korean version of the Hearing Handicap Inventory for the Elderly (K-HHIE) was administered to obtain the hearing handicap scores for each subject. After controlling for age, years of education, and depression levels, we found no significant differences in the K-HHIE scores between the MCI and the CNE groups. However, after we classified the MCI patients into the MCI with FED and MCI without FED groups, the MCI with FED group scored significantly higher than did both the MCI without FED and the CNE groups. In addition, after controlling for depression levels, significant partial correlations of hearing handicap scores with frontal-executive function scores and speech-in-noise perception performance were found in the MCI groups. In the CNE group, the hearing handicap scores were related to peripheral hearing sensitivity and years of education. In summary, MCI patients with FED are more likely to experience everyday hearing handicap than those without FED and cognitively normal old adults. Although educational level and peripheral hearing function are related to self-perceived hearing handicap in cognitively normal old adults, speech-in-noise perception and frontal-executive function are mainly associated with hearing handicap in patients with MCI