On weak spreadability of distributed-parameter systems and its achievement via linear--quadratic control techniques

In this paper, the concept of weak spreadability is introduced.It constitutes an extension of the idea developed by El Jai& Kassara. In the case of linear distributed systems weconsider quadratic control techniques with a conveniently penalizedcriterion which makes the system weakly spreadable. The approachis outlined for a convection—diffusion system, and theresults of a numerical study are also included to illustratethe main features of the considered problem.     

Computed tomographic imaging of the coronary arterial tree-use of local tomography

It has been demonstrated previously (see E.L. Ritman and A.A. Bove, in State of the Art in Quantitative Coronary Arteriography, p.67-78, 1986) that coronary artery anatomy can be visualized using high-speed, volume-scanning X-ray CT (computed tomography). In the current study it is demonstrated that local image reconstruction (i.e. the reconstruction kernel is ~2(+) mm long), as distinct from more conventional global image reconstruction (i.e. 200(+) mm kernel length), has the advantage of reducing the need for operator interactive image processing. In addition, the local reconstruction algorithm eliminates the need for recording the X-ray projection data over the full transaxial extent of the thorax because it requires only the X-ray attenuation data over the region of the heart. This latter aspect reduces the dynamic range requirements for the sensors and could reduce total X-ray exposure.     

Extraction of left-ventricular chamber from 3-D CT images of the heart

A semiautomatic method is described for extracting the volume and shape of the left ventricular (LV) chamber from a dynamic spatial reconstructor cardiac volume. For a given volume, the operator first performs some simple manual edits. Then, an automated stage, which incorporates concepts from 3-D mathematical morphology and technology, the maximum-homogeneity filter, and an adaptive 3-D thresholder, extracts the LV chamber. The method gives more consistent measurements and demands considerably less operator time than manual slice-editing.     

A method for quantitative display of three-dimensional regional myocardial function

The DSR (dynamic spatial reconstructor), a multiple X-ray source scanner that generates stop action three-dimensional (3-D) images of a cylindrical volume, was used for quantitative imaging of left ventricular 3-D wall geometry and function in experimentally induced canine left ventricular myocardial infarction. Impaired regional myocardial function was induced by myocardial ischemia or infarction in four mongrel dogs by closed-chest occlusion of the proximal left anterior descending (LAD) coronary artery. At intervals of 6-14 weeks post occlusion, the dogs were scanned with the DSR during biatrial contrast injection. The 3-D shape, extent, and function of hypokinetic myocardium was measured from the DSR images utilizing measurement of the rate of local systolic wall thickening to detect regions of normal, ischemic, or scarred myocardium. The results were compared to scar size and anatomic distribution measured at postmortem examination. The anatomic extent and relationship of hypocontractile to normally contracting muscle was visualized by computer generated, pseudo 3-D shaded surface displays of the left ventricular chamber and by topographic projections of regional wall thickening rates onto a map of the left ventricular endocardial surface. The location of myocardial infarction and the surrounding zone of impaired function is clearly defined by this 3-D CT scanning procedure. The display method presented here provides both localization and quantification of the volume of ischemic and infarcted myocardium.     

The ternary system H2O–Fe(NO3)3–Co(NO3)2 isotherms 0 and 15 °C

The solid–liquid equilibria of the ternary system H₂O–Fe(NO₃)₃–Co(NO₃)₂ were studied by using a synthetic method based on conductivity measurements.

Two isotherms were established at 0 and 15 °C, and the stable solid phases which appear are the iron nitrate nonahydrate (Fe(NO₃)₃·9H₂O), the iron nitrate hexahydrate (Fe(NO₃)₃·6H₂O), the cobalt nitrate hexahydrate (Co(NO₃)₂·6H₂O) and the cobalt nitrate trihydrate (Co(NO₃)₂·3H₂O).     

Ornamental Plant Efficiency for Heavy Metals Phytoextraction from Contaminated Soils Amended with Organic Materials

Accumulation of heavy metals (HMs) by ornamental plants (OPs) from contaminated agriculture soils is a unique technique that can efficiently reduce the metal load in the food chain. Amaranthus tricolor L. has attractive characteristics acquiring a higher growth rate and large biomass when grown at heavy metal contaminated soils. Site-specific detailed information is not available on the use of A. tricolor plant in metal phytoremediation from the polluted sites. The study aimed to enhance the uptake of HMs (Pb, Zn, and Cu) via amending poultry litter extract (PLE), vinasse sugarcane (VSC), and humic acid (HA) as natural mobilized organic materials compared to ethylene diamine tetraacetic acid (EDTA), as a common mobilized chemical agent by A. tricolor plant. The studied soils collected from Helwan, El-Gabal El-Asfar (Cairo Governorate), Arab El-Madabeg (Assiut Governorate), Egypt, and study have been conducted under pot condition. Our results revealed all organic materials in all studied soils, except EDTA in EL-Gabal El-Asfar soil, significantly increased the dry weight of the A. tricolor plant compared to the control treatment. The uptake of Pb and Zn significantly (p > 0.05) increased due to applying all organic materials to the studied soils. HA application caused the highest uptake as shown in Pb concentration by more than 5 times in Helwan soil and EDTA by 65% in El-Gabal El-Asfar soil while VSC increased it by 110% in El-Madabeg soil. Also, an increase in Zn concentration due to EDTA application was 58, 42, and 56% for Helwan, El-Gabal El-Asfar, and El-Madabeg soil, respectively. In all studied soils, the application of organic materials increased the remediation factor (RF) than the control. El-Madabeg soil treated with vinasse sugarcane gave the highest RF values; 6.40, 3.26, and 4.02% for Pb, Zn, and Cu, respectively, than the control. Thus, we identified A. tricolor as a successful ornamental candidate that, along with organic mobilization amendments, most efficiently develop soil health, reduce metal toxicity, and recommend remediation of heavy metal-contaminated soils. Additionally, long-term application of organic mobilization amendments and continued growth of A. tricolor under field conditions could be recommended for future directions to confirm the results.     

Selenium Alleviates the Adverse Effect of Drought in Oilseed Crops Camelina (Camelina sativa L.) and Canola (Brassica napus L.)

Drought poses a serious threat to oilseed crops by lowering yield and crop failures under prolonged spells. A multi-year field investigation was conducted to enhance the drought tolerance in four genotypes of Camelina and canola by selenium (Se) application. The principal aim of the research was to optimize the crop yield by eliciting the physio-biochemical attributes by alleviating the adverse effects of drought stress. Both crops were cultivated under control (normal irrigation) and drought stress (skipping irrigation at stages i.e., vegetative and reproductive) conditions. Four different treatments of Se viz., seed priming with Se (75 μM), foliar application of Se (7.06 μM), foliar application of Se + Seed priming with Se (7.06 μM and 75 μM, respectively) and control (without Se), were implemented at the vegetative and reproductive stages of both crops. Sodium selenite (Na₂SeO₃), an inorganic compound was used as Se sources for both seed priming and foliar application. Data regarding physiochemical, antioxidants, and yield components were recorded as response variables at crop maturity. Results indicated that WP, OP, TP, proline, TSS, TFAA, TPr, TS, total chlorophyll contents, osmoprotectant (GB, anthocyanin, TPC, and flavonoids), antioxidants (APX, SOD, POD, and CAT), and yield components (number of branches per plant, thousand seed weight, seed, and biological yields were significantly improved by foliar Se + priming Se in both crops under drought stress. Moreover, this treatment was also helpful in boosting yield attributes under irrigated (non-stress) conditions. Camelina genotypes responded better to Se application as seed priming and foliar spray than canola for both years. It has concluded that Se application (either foliar or priming) can potentially alleviate adverse effects of drought stress in camelina and canola by eliciting various physio-biochemicals attributes under drought stress. Furthermore, Se application was also helpful for crop health under irrigated condition.