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This paper focuses on the relation between the rheological and the morphological properties of immiscible polymer blends. Polystyrene droplets (PS) have been synthesized in the laboratory. The blends of EVA2840/PS at ratios 90/10, 70/30, and 50/50 (wt%/wt%) were prepared by Rheomix HAAKE 600VR internal batch mixer with roller rotor. Rheological tests were made at a temperature of 140 °C. Rheological measurements using a rotational rheometer with parallel-plate geometry are considered in order to lead to a better understanding of the dispersion of the PS droplets. Rheological examinations showed that the storage, the loss moduli, and the complex viscosity of blends have an extra elasticity at lower frequency. As a result, analysis of Han diagrams revealed that EVA2840/PS blend are immiscible.

This study deals with the behavior of a recycled polyethylene terephthalate (PET)/polypropylene (PP) blends. The compatibilizing effect has been investigated to examine the recycling feasibility in industrial production. The compatibilizing efficiency of olefinic copolymers containing epoxy groups for a/polypropylene (PET/PP) blends was examined using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), mechanical testing and rheological one. The effect of ethylene-glycidyl methacrylate (E-GMA, 92/8 wt%, Lotader AX8840) and ethylene–methyl acrylate-glycidyl methacrylate (E-MA-GMA, 68/24/8 wt%, Lotader AX8900) copolymers was investigated. The blends of PET/PP/compatibilizer at compositions 80/15/5, 85/11.25/3.75, 90/7.5/2.5 and 95/3.75/1.25 (wt%) were prepared by melt mixing in a single-screw extruder. Test specimens were prepared by compression moulding at processing temperatures of 250 °C. The incorporation of the compatibilizers has a large effect on the dispersion of the PP phase. Moreover, the copolymer was more efficient than the terpolymer. Especially, E-GMA was found to improve the elongation at break of the blends containing 80 % PET.

Lawsonia inermis L., (Lythraceae), commonly known as henna, Is a shrub or small tree frequently cultivated in India, the middle East, and along the African coast of the Mediterranean Sea (Hutchison and Dalzial 1954). Powdered leaves of this plant, in the form of a paste; axe used as a cosmetic for staining hands and hair. The dyeing property, as well as the antispasmodic (Fahim and Hossein 1954) and bacteriostatic properties (Hoffmann et al. 1947), were attributed to the presence of lawsone (1); a 2-hydroxy-l,4-naphthoquinone. The occurrence of gallic acid, flavonoids, coumarins, xan-thones, and phenolic glycosides in Lawsonia leaves has also been reported (Anand et al. 1992).

An ELISA-assay for the detection and the semi-quantitative determination of taxane diterpenoids structurally related to taxol found in Taxus sp. has been developed. The antiserum was raised in rabbits using a 2'-succinyltaxol-bovine serum albumin conjugate as immunogen. The working range of the assay was from 1 to 100 ng of taxol. In order to improve the production of taxol, preliminary experiments have been performed on crude extracts of several Taxus sp.; the results indicate that the present immunoassay is an useful tool for the rapid screening of species, varieties or individual plants out of a large population as well as for tissue cultures analysis.

Conflicting opinions exist concerning clinical and pathological presentation, as well as evolution and prognosis, of breast cancer in young women. The roles of associated pregnancy and lactation on these parameters is also unclear. These two conditions are studied in the present work through the comparison of two breast cancer patient age groups: patients under the age of 30 (Group A) and premenopausal patients aged 45–49 (Group B). Rapidly growing and/or inflammatory breast cancer (rapidly progressing breast cancer: RPBC) — a special form of Breast Cancer with a poor prognosis very frequent in the Tunisian breast cancer population — was more often present among Group A patients. This difference is a consequence of the more frequent association of this breast cancer group with pregnancy or lactation; nearly all the cases of breast cancer associated with pregnancy or lactation are RPBC. For breast cancer without the pregnancy/lactation association, the younger group generally shows poorer histological grading and more severe evolution. The number of patients in our study is not really sufficient to allow statistically significant conclusions, but it does seem clear that young age and associated pregnancy/lactation are aggravating factors in Tunisian breast cancer patients.

Based on two pretreatment evaluations, doubling time (DT) was calculated in 75 cases of invasive breast cancer (BC). The cases studied were more or less equally distributed between three DT groups: fast-growing tumors (DT less than 90 days), intermediate cases (DT between 90 and 180 days), and slow-growing tumors (DT greater than 180 days. A correlation was found to exist between DT and patient age and, to an even greater extent, between DT and pathologic prognostic indicators such as histologic grading and nuclear grade. Inflammatory symptoms were not associated with DT, but were closely related to the size of the tumor and regional lymph node involvement. The date of detection of distant metastases depended heavily on the DT of the BC:BC with shorter DT = earlier metastatic spread. The presence of inflammatory signs was also decisive: within each DT category, inflammatory BC metastases were both more frequent and precocious.

L'etude des proprietes rheologiques a l'etat fondu de materiaux composites a base de farines de bois ou de bois retifie et de polyethylene basse densite apolaire ou de copolymeres d'ethylene polaires, a ete effectuee a differentes vitesses de cisaillement. Le comportement des melanges varie avec le degre de torrefaction du bois et la nature polaire ou apolaire de la matrice. Une interpretation de ces differences de comportement, basees sur les interactions fibres-matrices, a ete proposee. Des mesures d'essais mecaniques, effectuees sur des eprouvettes composites, confirment les resultats presentes a l'etat fondu. // Investigation of the molten state properties of composite materials based on powdered pine or torrefied pines and low density polyethylene or ethylene copolymers is carried out at different shear rates. Mixtures with a polyethylene matrix exhibit a different behaviour compared to those based on copolymers. An interpretation of these differences based on fibre/matrix interactions is proposed. Mechanical tests carried out on composite test-bars corroborate the results obtained from the molten state.

Clinical and radiographic examination of 581 patients with histologically veri-fied breast cancer has permitted us to define a subgroup having a significantly poorer prognosis than other patients. Their condition, called “poussee evolu-tive” (rapidly progressing), is characterized by rapid tumor growth and/or inflammation adjacent to the tumor. Statistical analysis of the survival of Mo patients (412 of the 581) shows that the diagnosis of “poussee evolutive” provides prognostic information beyond that given by T and N classifications and after delay between initial symptoms and diagnosis has been considered. Six years of clinical experience with this condition are discussed. Cancer 40:376–382, 1977.