Résumé
OBJECTIVE: This randomized controlled trial aimed to compare the stability of mandibular arch orthodontic treatment outcomes between passive self-ligating and conventional systems during 6 months of retention. METHODS: Fortyseven orthodontic patients with mild to moderate crowding malocclusions not requiring extraction were recruited based on inclusion criteria. Patients (mean age 21.58 ± 2.94 years) were randomized into two groups to receive either passive self-ligating (Damon® 3MX, n = 23) or conventional system (Gemini MBT, n = 24) orthodontic treatment. Direct measurements of the final sample comprising 20 study models per group were performed using a digital caliper at the debonding stage, and 1 month, 3 months, and 6 months after debonding. Paired t-test, independent t-test, and non-parametric test were used for statistical analysis. RESULTS: A significant increase (p < 0.01) in incisor irregularity was observed in both self-ligating and conventional system groups. A significant reduction (p < 0.01) in second interpremolar width was observed in both groups. Mandibular arch length decreased significantly (p = 0.001) in the conventional system group but not in the self-ligating system group. A similar pattern of stability was observed for intercanine width, first interpremolar width, intermolar width, and arch depth throughout the 6-month retention period after debonding. Comparison of incisor irregularity and arch dimension changes between self-ligating system and conventional system groups during the 6 months were non-significant. CONCLUSIONS: The stability of treatment outcomes for mild to moderate crowding malocclusions was similar between the self-ligating system and conventional system during the first 6 months of retention.
Sujets)
Adulte , Humains , Surpeuplement , Incisive , Malocclusion dentaireRésumé
O manejo agrícola interfere nas condições físicas, químicas e biológicas do solo, na capacidade produtiva do sistema agrícola e na susceptibilidade do solo ao processo erosivo, não raramente acentuando-a. Objetivou-se, neste estudo, estudar a influência de dois sistemas de manejo sobre a qualidade física de um Latossolo Vermelho Distroférrico típico da região de Campinas, SP, bem como seus efeitos tanto no desenvolvimento e produtividade da cultura do milho, quanto no controle das perdas de terra e de nutrientes por erosão. Foram comparados dois sistemas de manejo, sistema plantio direto (SPD) e sistema convencional com grade aradora (SC), aplicando-os em parcelas experimentais dotadas com sistemas coletores de enxurrada para avaliação das perdas de terra e de nutrientes por erosão. Também foram analisados atributos físicos e químicos do solo, bem como dados biométricos e de produtividade da cultura do milho. Os resultados evidenciam que o manejo agrícola influenciou a qualidade do solo, sendo que os indicadores físicos foram melhores no sistema convencional. No entanto, os indicadores biométricos, em especial altura de plantas, foram superiores no sistema plantio direto. Também houve influência do manejo sobre o controle da erosão, ocorrendo maiores perdas de solo e de nutrientes, em particular, de fósforo e de matéria orgânica nas parcelas sob SC.
Agricultural management influences the physical, chemical and biological conditions of the soil, affecting soil quality, the productivity capacity of the agricultural system and its vulnerability to erosion process, frequently increasing it. The purpose of this work was to study the influence of two agricultural management systems on physical soil quality of a Rhodic Hapludox occurring in Campinas, State of São Paulo, and their effects not only on corn crop development and yield, but also on soil and nutrient loss by erosion. Two management systems were compared, named direct drilling system (DDS) and conventional system (CS), by applying them in experimental plots having runoff collectors to assess soil and nutrient losses by erosion. Soil physical and chemical attributes were also analyzed, as well as biometrical and yield data of the corn crop. The results indicate that agricultural management has differently influenced soil quality, and that soil physical indicators were better under the conventional system (CS). However, biometrical indicators, especially plant height, were superior under direct drilling system (DDS). There was also influence of agricultural management on erosion control, occurring greater soil losses and particularly larger phosphorous and organic matter losses from plots under conventional system (CS).
Résumé
The purpose of this study was to investigate the operation and management systems of the school food services in Korea and to provide useful data for improving the quality of the school food services. This study was conducted in school food service operations nationwide using a written questionnaire. The questionnaires were mailed to the dieticians of three types of school food service systems-conventional, commissary, and joint-management. Of the 660 schools that participated in this study, the responses from 212 conventional system, 212 commissary system and 200 joint-management system services were selected for analysis. Statistical analysis was performed utilizing the SAS/Win 6.12 program so as to provide a descriptive statistics. The main results of this study can be summarized as follows: The average number of meals served per day was 1014, 738 and 695 in the conventional food service, the commissary food service and the joint-management food service systems, respectively. Over half (58.9%) of food service facilities were utilizing computer programs for their operations. Most of the commissary food service systems (52.4%) had a satellite school and served a maximum of 2000 meals per day. In most of the joint-management food service systems (87.1%), the number of food service schools managed was two and a maximum of 3330 meals were served. Only one dietician was posted irrespective of the school food service system. The mean hours of work by the dietician per day was 8.9, 8.6 and 8.6 in the conventional food service, the commissary food service and the joint-management food service systems, respectively. The principal work functions of cook personnel were cooking and cleaning.