Identification of plant leaf phosphorus content at different growth stages based on hyperspectral reflectance.

BACKGROUND: Modern agriculture strives to sustainably manage fertilizer for both economic and environmental reasons. The monitoring of any nutritional (phosphorus, nitrogen, potassium) deficiency in growing plants is a challenge for precision farming technology. A study was carried out on three species of popular crops, celery (Apium graveolens L., cv. Neon), sugar beet (Beta vulgaris L., cv. Tapir) and strawberry (Fragaria × ananassa Duchesne, cv. Honeoye), fertilized with four different doses of phosphorus (P) to deliver data for non-invasive detection of P content. RESULTS: Data obtained via biochemical analysis of the chlorophyll and carotenoid contents in plant material showed that the strongest effect of P availability for plants was in the diverse total chlorophyll content in sugar beet and celery compared to that in strawberry, in which P affects a variety of carotenoid contents in leaves. The measurements performed using hyperspectral imaging, obtained in several different stages of plant development, were applied in a supervised classification experiment. A machine learning algorithm (Backpropagation Neural Network, Random Forest, Naive Bayes and Support Vector Machine) was developed to classify plants from four variants of P fertilization. The lowest prediction accuracy was obtained for the earliest measured stage of plant development. Statistical analyses showed correlations between leaf biochemical constituents, phosphorus fertilization and the mass of the leaf/roots of the plants. CONCLUSIONS: Obtained results demonstrate that hyperspectral imaging combined with artificial intelligence methods has potential for non-invasive detection of non-homogenous phosphorus fertilization on crop levels.

[Treatment methods in various stages of the pathway to psychiatric care]. / Metody leczenia proponowane pacjentom na poszczególnych etapach "drogi" do psychiatry.

AIM: The aim of this study was to analyse the treatment methods at the different stages of the pathway to psychiatric care. METHOD: In a period of two months all patients age 15 and over who applied to the Psychiatric Service in the Zabkowice catchment area and Psie-Pole catchment area were assessed by psychiatrists for their eligibility to enter the study. Those who had fulfilled the entry criteria were interviewed using a Polish version of WHO's encounter form (EF) by the mental health professionals during their initial interview. RESULTS: A total of 228 patients (105 men and 123 women) were seen. Encounter forms were completed on 200 people. 28 patients refused to answer some of the questions. There were significant differences in treatments offered to patients by hospital doctors and medical specialists, general practitioners (GP's) and psychiatrists. Our data show that sedative/hypnotics are the main psychotropic drugs prescribed by GP's. The small percentage of antidepressant (10% of all psychotropic drugs) used by GP's and medical specialists was noteworthy. They didn't decide to prescribe neuroleptics to their patients. CONCLUSIONS: The study revealed that GP's, hospital doctor & medical specialists prescribed antidepressant and neuroleptics far too rarely and GP's far too often prescribed sedative/hypnotics. This can indicate that they have difficulties in diagnosing of mental disorders as well as poor knowledge concerning indications relating the use of psychotropic drugs.