Fuzzy clustering algorithm to identify the effects of some soil parameters on mechanical aspects of soil and wheat yield

In this paper, site-specific management zones (MZs) were delineated in three fields belonging to a farm in the center of Italy and characterized by different soil texture. Crop yield and various soil parameters, both physical (soil structural stability, clay fraction, water content, and organic matter) and mechanical (shear strength and penetration resistance) were monitored. Yield data were acquired by means of a combine harvester equipped with a precision land management system during three consecutive growing seasons. At the end of the third growing season, soil properties were investigated by means of georeferenced soil sampling. After data gathering, a fuzzy clustering algorithm was applied to define management zones. Results highlighted spatial variability between the three fields and temporal variability between the three consecutive growing seasons. Whilst the latter could be ascribed to the rainfall distribution (therefore moisture could be considered as a limiting factor in wheat growth), the delineated MZs suggest that clay content and organic matter could affect both mechanical parameters of soil and crop yield. The defined MZs can serve as a basis to generate prescription maps for variable-rate application inputs and variable tillage

Influence of tyres characteristics and travelling speed on ride vibrations of a modern medium powered tractor Part I: Analysis of the driving seat vibration

In the present investigation a contribution is offered in order to improve the knowledge of the influence of both speed and tyre type on a medium power tractor vibrations.  The vibrations transmitted from the ground to the driver’s seat of a ballasted wheeled tractor of medium power, equipped with a front suspension axle and a suspended cab, have been measured and analyzed.  Two different tyres, namely, types A and B, at two different forward speeds, 11.1 and 13.9 m s-1, have been experimentally tested, during the simulation of the front agricultural implements transportation on a rectilinear plane tract of a conglomerate bituminous closed track.  This work has been done by applying standards recommended by ISO 2631/1, 1997.  Results were obtained on the basis of the measurement of both the root-mean-square (RMS) acceleration and the frequency analysis, conducted for any axis on the tractor rear axle and on the operator seat.  In particular, different results were obtained for the two tyres and along all the axes.  Furthermore, the acceleration was not strictly proportional to the forward speed increases.   Keywords: tractors, high speed, whole body vibrations, tyre

Influence of tyres characteristics and travelling speed on ride vibrations of a modern medium powered tractor Part I: Analysis of the driving seat vibration

In the present investigation a contribution is offered in order to improve the knowledge of the influence of both speed and tyre type on a medium power tractor vibrations.  The vibrations transmitted from the ground to the driver’s seat of a ballasted wheeled tractor of medium power, equipped with a front suspension axle and a suspended cab, have been measured and analyzed.  Two different tyres, namely, types A and B, at two different forward speeds, 11.1 and 13.9 m s-1, have been experimentally tested, during the simulation of the front agricultural implements transportation on a rectilinear plane tract of a conglomerate bituminous closed track.  This work has been done by applying standards recommended by ISO 2631/1, 1997.  Results were obtained on the basis of the measurement of both the root-mean-square (RMS) acceleration and the frequency analysis, conducted for any axis on the tractor rear axle and on the operator seat.  In particular, different results were obtained for the two tyres and along all the axes.  Furthermore, the acceleration was not strictly proportional to the forward speed increases.   Keywords: tractors, high speed, whole body vibrations, tyre

Influence of tyres characteristics and travelling speed on ride vibrations of a modern medium powered tractor Part II, Evaluation of the Health Risk

In this paper, according to ISO 2631/1, 1997, the influence of the mechanical vibrations on human health is evaluated and assessed with four methods: the health guidance caution zones (HGCZ), the estimated vibration dose value (eVDV), the fourth power vibration dose value (VDV), a combination of various methods presented in literature.  The normative refers to the HGCZ, which involves the average RMS vibration emission level and its exposure time during a given working day.  Values of crest factor for the operator seat showed that Z-axis was the more solicited, even if all the crest factor values are below 9.  Results of mechanical vibration in respect of comfort and health, according with the method of the HGCZ, showed that only case B, at higher forward speed, does not exceed the lower boundary of the zone.  According to the fourth power vibration dose method and ratios for comparison of basic and additional methods of evaluation, the results showed that only case A, at lower forward speed, does not exceeded 1.25.   Keywords: whole body vibration, tractor, comfort, health risk, tyres

A Koopman Operator Tutorial with Othogonal Polynomials

The Koopman Operator (KO) offers a promising alternative methodology to solve ordinary differential equations analytically. The solution of the dynamical system is analyzed in terms of observables, which are expressed as a linear combination of the eigenfunctions of the system. Coefficients are evaluated via the Galerkin method, using Legendre polynomials as a set of orthogonal basis functions. This tutorial provides a detailed analysis of the Koopman theory, followed by a rigorous explanation of the KO implementation in a computer environment, where a line-by-line description of a MATLAB code solves the Duffing oscillator application.Comment: 22 pages. arXiv admin note: text overlap with arXiv:2110.1211

A Koopman-Operator Control Optimization for Relative Motion in Space

A high order optimal control strategy implemented in the Koopman operator framework is proposed in this work. The new technique exploits the Koopman representation of the solution of the equations of motion to develop an energy optimal inverse control methodology. The operator theory can reformulate a nonlinear dynamical system of finite dimension into a linear system with an infinite number of dimensions. As a results, the state of any nonlinear dynamics is represented as a linear combination of high-order orthogonal polynomials, which creates the state transition polynomial map of the solution. Since the optimal control technique can be reduced to a two-points boundary value problem, the Koopman map is used to connect the state and control variables in time, such that optimal values are obtained through map inversion and polynomial evaluation. The new technique is applied to rendezvous applications in space, where the relative motion between two satellites is modelled with a high-order polynomial series expansion of the Lagrangian of the system, such that the Clohessy-Wiltshire equations represent the reduction of the high-order model to a linear truncation.Comment: 19 pages, 9 figures, 2023 SciTech conference. arXiv admin note: text overlap with arXiv:2111.0748

Quality of life in Parkinson’s disease: Italian validation of the Parkinson’s Disease Questionnaire (PDQ-39-IT)

Translation and cross-cultural adaptation of the 39-item Parkinson’s Disease Questionnaire (PDQ-39) to the Italian culture was performed by Oxford University Innovation in 2008, but this version has never been validated. Therefore, we performed the process of validation of the Italian version of the PDQ-39 (PDQ-39-IT) following the “Consensus-Based Standards for the Selection of Health Status Measurement Instruments” checklist. The translated PDQ-39-IT was tested with 104 patients diagnosed with Parkinson’s disease (PD) who were recruited between June and October 2017. The mean age of the participants was 65.7 ± 10.2 years, and the mean duration of symptoms was 7.4 ± 5.3 years. The internal consistency of the PDQ-39-IT was assessed by Cronbach’s alpha and ranged from 0.69 to 0.92. In an assessment of test-retest reliability in 35 of the 104 patients, the infraclass correlation coefficient (ICC) ranged from 0.85 to 0.96 for the various subitems of the PDQ-39-IT (all p < 0.01). Spearman’s rank correlation coefficient for the validity of the PDQ-39-IT and the Italian version of the 36-Item Short Form (SF-36) was − 0.50 (p < 0.01). The results show that the PDQ-39-IT is a reliable and valid tool to assess the impact of PD on functioning and well-being. Thus, the PDQ-39-IT can be used in clinical and research practice to assess this construct and to evaluate the overall effect of different treatments in Italian PD patients

Perception d'une insuffisance de lait au cours des 2 premiers mois d'allaitement : prévalence et impact chez les primipares au CHU Estaing de Clermont-Ferrand

In France, various studies show that mother's perception of insufficient milk supply is the first reason of early weaning (38% of the cases), and early introduction of baby formulas. In 2012, 22.5 % of French infants were still breastfed at the age of 6 months, and among them 10.5% were exclusively breastfed. This duration for breastfeeding meets neither the expectations of women nor the standards of the World Health Organization (WHO) which recommends exclusive breastfeeding for the first six months.Our study, conducted with women breastfeeding their first baby after leaving the hospital CHU Estaing of Clermont-Ferrand, between the 24th and the 27th of May 2014, shows that 76.7% of women confirm feeling this insufficient milk supply during the first 2 months of breastfeeding.Those periods of perception of insufficient milk supply have consequences on the continuation of breastfeeding. Indeed only 43.6% of the mothers continue to breastfeed exclusively. Our study also allows us to characterize those periods in detail.We observed a significant connection between the perception of insufficient milk supply and the use of a pacifier. Moreover, we observed a connection between giving a bottle of formula milk while feeling an insufficient milk supply and the BMI of women, their motivation to breastfeed, their self-confidence in feeding their babies, the night feedings and the frequency, duration and intensity of these periods, the perception of insufficient milk supply shortly after giving birth, the growing chart of the baby and the continuation of the breastfeeding at 2 months. Nevertheless, our study -unlike other studies- didn't show a connection between point-supplementing with formula in the hospital (with a very strong prevalence: 73.8%) and the feeding mode at 2 months or the periods of lacking lactation. This study shows that there is a real need to improve information, support and prevention with new mothers. A breastfeeding consultant should be assigned between day 8 and day 15. The healthcare professionals should also submit to ongoing in-service training.En France, dans la littérature, la perception maternelle d’une insuffisance de lait est la raison la plus fréquemment mentionnée pour la cessation précoce de l’allaitement (38 % des cas) ou l’introduction de préparations commerciales pour nourrissons. En 2012, 22,5% des bébés français étaient encore allaités à 6 mois, dont seulement 10,5 % de façon exclusive, alors que l'OMS recommande un allaitement exclusif de 6 mois.Notre étude, menée auprès des primipares allaitant leur enfant en sortie de maternité du CHU Estaing de Clermont-Ferrand, entre le 24 mars et le 27 mai 2014, a montré une très grande prévalence de périodes de perception de manque de lait au cours des 2 premiers mois d'allaitement. En effet, 76,7% des femmes ont déclaré avoir eu cette sensation d'insuffisance de lait au cours des 2 premiers mois d'allaitement (IC95% =[67,3 – 84,5]).Ces périodes d'insuffisance de lait ont d'importantes conséquences sur la poursuite de l'allaitement car, à l'issue de ces périodes, seulement 43,6 % des mères poursuivent un AM exclusif. L'étude a également permis de caractériser plus en détails ces périodes.Des liens statistiquement significatifs avec la survenue d'épisodes de sensation de manque de lait ont été seulement mis en évidence avec le fait que l'enfant ait une tétine. En revanche, des liens statistiquement significatifs ont été mis en évidence entre le fait de donner un biberon de lait artificiel lors de sensations de manque de lait et l'IMC de la femme, sa motivation à allaiter, son niveau de confiance en elle et en sa capacité à nourrir son enfant, les tétées nocturnes, la fréquence, la durée et l'intensité de ces périodes, l'impression de manquer de lait dès le séjour en maternité, la courbe de croissance de l'enfant, la poursuite de l'allaitement et le mode d'allaitement à 2 mois. En revanche, de façon surprenante par rapport à la littérature, notre étude n'a pas montré de lien entre le fait de donner du lait artificiel ponctuellement en maternité (avec une très forte prévalence : 73,8%) et le mode d'allaitement à 2 mois ou la survenue de périodes de manque de lait.Cette étude montre qu'il faut améliorer l'accompagnement, l'information et la prévention auprès des femmes. Une consultation d'allaitement devrait être systématisée entre j8 et j15. La formation des professionnels de santé est elle aussi à poursuivre

Phenotypic effects of expanded ataxin-1 polyglutamines with interruptions in vitro

Spinocerebellar ataxia type 1 is a neurodegenerative disease caused by expansion of an uninterrupted glutamine repeat in ataxin-1 protein. Protein aggregation and immunoreactivity to 1C2 monoclonal antibody are two distinct pathognomonic features of expanded ataxin-1, as well as of other polyglutamine disorders. Rare cases of non-affected elderly subjects carrying expanded ataxin-1 alleles were found in random population. However, in these alleles the glutamine stretch was interrupted by histidines. Due to lack of phenotype, these alleles should be considered "normal". Most importantly, occurrence of these unusual alleles provides a unique opportunity to investigate which molecular properties of expanded ataxin-1 are not coupled to polyglutamine pathogenesis. Towards this goal, we compared in vitro the immunoreactivity to 1C2 antibody and the ability to form aggregates of interrupted and uninterrupted alleles. Immunoblotting showed that expanded-interrupted ataxin-1 had an affinity to 1C2 resembling that of normal ataxin-1. On the contrary, filter assay showed that aggregation rate of expanded-interrupted ataxin-1 resembles that of expanded-uninterrupted ataxin-1. These observations indicate that affinity for 1C2 does not directly correlate with self-aggregation of ataxin-1. Moreover, self-aggregation is not directly affected by histidine interruptions. In conclusion, these results support the hypothesis that mechanisms underlying neuronal degeneration are triggered by protein misfolding rather than by protein aggregation