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1.
PLoS One ; 19(1): e0296684, 2024.
Article in English | MEDLINE | ID: mdl-38285649

ABSTRACT

Sustainable intensification of agriculture requires understanding of the effect of soil characteristics and nutrient supply on crop growth. As farms are increasing in size by acquiring small fields from various farmers, the soil characteristics and nutrient supply might be very different from field to field, while at the same time specific soil properties might limit the nutrient uptake. As a result, there might be a large number of heterogeneous reasons why crop growth varies significantly. New data analysis techniques can help to explain variability in crop growth among fields. This paper introduces Exceptional Growth Mining (EGM) as a first contribution. EGM instantiates the data mining framework Exceptional Model Mining (EMM) such that subgroups of fields can be found that grow exceptionally in terms of three growth parameters (high/low maximum growth, steep/flat linear growth and early/late midpoint of maximum growth). As second contribution, we apply EGM to a case study by analyzing the dataset of a potato farm in the south of the Netherlands. EGM consists of (i) estimating growth curves by applying nonlinear mixed models, (ii) investigating the correlation between the estimated growth parameters, and (iii) applying EMM on these growth curve parameters using a growth curve-specific quality measure. By applying EGM on the data of the potato farm, we obtain the following results: 1) the estimated growth curves represent the variability in potato tuber growth very well (R2 of 0.92), 2) the steepness of the growth curve has a strong correlation with the maximum growth and the midpoint of maximum growth, and the correlation between the midpoint of maximum growth and maximum growth is weak, 3) the subgroup analyses indicate that: high values of K correspond to high maxima; low values of K correspond to low maxima, steep growth curves', and a late midpoint of halfway growth; Mg influences the midpoint of the growth curve; values of B are higher on dry soils with high tuber growth, while low values of B are found on wet soils with high tuber growth; high values of Zn, Mn, and Fe are found in subgroups with low tuber weight, probably related to the soil's low pH. In summary, this paper introduces EGM to obtain understanding in crop response to soil properties and nutrient supply. In addition, EGM provides a way to analyze only small parts of a large dataset, such that the impact of soil factors on growth can be analyzed on a more detailed level than existing methods.


Subject(s)
Agriculture , Soil , Soil/chemistry , Farms , Agriculture/methods , Nutrients , Netherlands
2.
Plast Reconstr Surg ; 132(6): 913e-923e, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24281638

ABSTRACT

BACKGROUND: The authors tested a short, practically designed questionnaire to assess changes in subjective perception of nasal appearance in patients before and after aesthetic rhinoplasty. METHODS: A prospective cohort study was conducted in a group of 121 patients who desired aesthetic rhinoplasty and were operated on by one surgeon. The questionnaire contained five questions (E1-E5) based on a five-point Likert scale and a visual analogue scale (range, 0 to 10). Two questions were designed as trick questions to help the surgeon screen for signs of body dysmorphic disorder. RESULTS: All patients rated the appearance of their nose as improved after surgery. The visual analogue scale revealed a Gaussian curve of normal distribution (range, 0.5 to 10) around a significant improvement (mean, 4.36 points, p = 0.018). Also, question E1, question E2, and the sum of questions E1 through E5 showed a statistically significant improvement after surgery (p = 1.74 × 10, p = 4.29 × 10, and p = 9.23 × 10, respectively). The authors found a linear relationship between preoperative score on the trick questions and postoperative increase in visual analogue scale score. Test-retest reliability could be investigated in 74 of 121 patients (61 percent) and showed a positive correlation between postoperative (1 year after surgery) and repostoperative response (2 to 4 years after surgery). CONCLUSIONS: The authors concluded that a surgeon performing aesthetic rhinoplasty can benefit from using this questionnaire. It is simple, takes no more than 2 minutes to complete, and provides helpful subjective information regarding patients' preoperative nasal appearance and postoperative surgical outcome. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.


Subject(s)
Esthetics/psychology , Nose , Patient Satisfaction , Rhinoplasty/psychology , Surveys and Questionnaires/standards , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged , Perception , Postoperative Period , Prospective Studies , Young Adult
3.
Arch Facial Plast Surg ; 14(5): 346-53, 2012.
Article in English | MEDLINE | ID: mdl-22986942

ABSTRACT

OBJECTIVES: To describe the split hump technique (SHT) and to examine its effectiveness for correction of an overprojected nasal dorsum in patients undergoing aesthetic rhinoplasty. METHODS: This prospective study included 97 patients. Objective assessment was performed using a short, practical questionnaire. Investigation focused on nasal patency and the patient perception of body image in relation to nasal appearance using 5-point Likert scale questions and visual analog scales. RESULTS: Use of the SHT resulted in a significant improvement in nasal patency and aesthetic nasal perception. Sum functional question scores decreased from 9.154 to 6.351 and aesthetic question scores from 13.897 to 6.825 (P < .001 for both). Mean aesthetic visual analog scale scores improved in all patients, from 3.346 to 7.782 (P < .001). Graphic illustration of this improvement revealed a gaussian curve of normal distribution around a mean (SD) improvement of 4.48 (1.93). CONCLUSIONS: Traditional en bloc humpectomy maneuvers are frequently combined with spreader graft use to avoid postoperative inferomedial repositioning of the upper lateral cartilages and inverted-V deformity. The SHT for correction of the overprojected dorsum creates a paradigm change in this patient group. The transverse segments of the upper lateral cartilages are saved and repositioned instead of being resected as a part of an en bloc osseocartilaginous composite hump resection in a transverse plane. Several modifications of the SHT enable the surgeon to deproject the nose while keeping sufficient strength in the keystone area and augmenting dorsal width. Using statistical analysis of subjective patient data, we could prove a broad acceptance and appreciation for the SHT.


Subject(s)
Body Image , Nasal Cartilages/surgery , Nasal Septum/surgery , Patient Satisfaction/statistics & numerical data , Rhinoplasty/methods , Adolescent , Adult , Aged , Esthetics , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prospective Studies , Rhinoplasty/psychology , Surveys and Questionnaires , Young Adult
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