Dynamical local models for segmentation and prediction of financial time series

In the analysis and prediction of many real-world time series, the assumption of stationarity is not valid. A special form of non-stationarity, where the underlying generator switches between (approximately) stationary regimes, seems particularly appropriate for financial markets. We introduce a new model which combines a dynamic switching (controlled by a hidden Markov model) and a non-linear dynamical system. We show how to train this hybrid model in a maximum likelihood approach and evaluate its performance on both synthetic and financial data

Multi-Response Optimization For Industrial Processes

Process optimization is a very important point in modern industry. There are many classical optimization methods, which can be applied when some mathematical conditions are verified. Real situations are not very simple so that classical methods may not succeed in optimizing; as in cases when the optimization has several contradictory objectives (Collette, 2002). The purpose of this work is to propose an optimization method for industrial processes with multiple inputs and multiple outputs (MIMO), for which the optimization objectives are generally contradictory and for which some objectives are not maximum or minimum but performance criteria. The first step of this method is modeling each process response by a quadratic model. After establishing the model, we use a simplified numerical optimization algorithm in order to determine values of the parameters allowing optimizing the different responses, for MIMO processes. This method will also allow finding optimum target values for multiple inputs single output processes

The influence of humic acids extracted from Chaouia soil on the behavior of transition metal ions and pesticides

      Humic acid (HA) and fulvic acid (FA) exist ubiquitously in environments and have a variety of functional groups, which allow them to complex with metal ions and pesticides. Furthermore, these interactions can not only alter the environmental behavior, but also influence the removal and transportation of those pollutants. The study of the interaction between Cu (II), VO (II) and Mn (II) with HAs provides environmental information on the oxidation states of paramagnetic metals and their mechanisms of binding to humic acids. Electron spin resonance (ESR) study demonstrates that VO (II) and Cu (II) ions are bound with oxygen ligands to HAs, while the Mn (II) complex occurs as [Mn(H2O)6]2+. Additionally, Cu (II) ions are more strongly bound than Mn (II) ions to soil HAs. The effect of the presence of HA on photolysis of Tribenuron-methyl (TRB) and Imazapyr (IMAZ) herbicides in water was studied by irradiation of different mixtures of HA/herbicide (0.5:1 and 1:1 by volume). The obtained results clearly demonstrate that HA substances exhibit a screening effect on the photochemical degradation of the two herbicides. The protective effect of HAs on the TRB and IMAZ degradation could be explained with an inclusion and/or adsorption of the herbicide molecules in the humic matrix

Study of the effect of chromium on the germination parameters of Fenugreek (Trigonella foenum-gracium L.) and Lens (Lens culinaris)

Received: September 21st, 2022 ; Accepted: January 2nd, 2023 ; Published: February 8th, 2023 ; Correspondence: [email protected] contamination by heavy metals is a global environmental problem. This contamination affects agricultural crops in the area concerned. In the present study, chromium, which is a heavy metal, is evaluated for its diverse effects on seed germination and lateral growth of fenugreek and lens seeds. A chromium solution was prepared at increasing concentrations: 0, 0.02, 0.04, 0.06, 0.08, 0.1, and 0.2 mg L-1 for the addition of germinating seeds in petri dishes for ten days. After two days, the germination rate is calculated. For the following days the length of radicle, stem, and number of leaves are measured. The germination rate of fenugreek varies between 100 and 73.33% for the control and 0.02 mg L-1 of chromium respectively. However, the germination rate of the lens varies between 100% for the control and 90% for the 0.02 mg L-1 . The elongation of fenugreek radicle with chromium solutions shows a significant effect. However, there is no significant difference in the lens at the different concentrations. For the growth of the fenugreek stalk, it is noticed that the concentration 0.02 shows a length of 2.83 cm compared to their control which is 2.30 cm. Consequently, chromium at 0.02 mg L-1 stimulates growth, but at 0.2 mg L-1 , it inhibits it. For lens the length of the stems shows also a significant difference compared to their control. So the effect of chromium on germination parameters depends on their concentrations, as well as on the seed response itself. For our research the response of fenugreek compared to the lens at the same concentrations is different

Histopathology of prostate tissue after vascular-targeted photodynamic therapy for localized prostate cancer

Low-risk prostate adenocarcinoma is classically managed either with active surveillance or radical therapy (such as external radiotherapy or radical prostatectomy), but both have significant side effects. Vascular-targeted photodynamic therapy (VTP) is a focal therapy proposed as an alternative approach for localized, low-volume, and low-Gleason score (≤6) carcinomas. We report histological modifications observed in prostate biopsies of 56 patients, performed 6 months after VTP using the photosensitizer TOOKAD® Soluble (WST11) and low-energy laser administered in the tumor area transperineally by optic fibers. In 53 patients, we observed sharply demarcated hyaline fibrotic scars, with or without rare atrophic glands, sometimes reduced to corpora amylacea surrounded by giant multinuclear macrophages. Mild chronic inflammation, hemosiderin, and coagulative necrosis were also observed. When residual cancer was present in a treated lobe (17 patients), it was always located outside the scar, most often close to the prostate capsule, and it showed no therapy-related modification. Histopathological interpretation of post-WST11 VTP prostate biopsies was straightforward, in contrast with that of prostate biopsies after radio or hormonal therapy, which introduces lesions difficult to interpret. VTP resulted in complete ablation of cancer in the targeted area