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A non-isothermal model based on linear driving force approximation for a system like CO2 – moisture – N2 – molecular sieve, 5A predicted the experimental results satisfactorily for simultaneous adsorption of CO2 and moisture in a fixed bed. Moisture being the strongly adsorbed component forces carbon dioxide (weakly adsorbed component) to be rolled up. The thermophysical and transport properties of moisture mainly governs the dynamics of the process, control or manipulation of which could give better separation by adsorption of one component from the other lying together in a stream. The major parameters are inlet adsorbate concentration, particle Reynolds number, bed diameter to bed length ratio, Schmidt number, Equilibrium Distribution coefficient, Sherwood number, and Kutateladze number. Un modele non isotherme base sur l'approximation de la force motrice lineaire pour un systeme comme un tamis moleculaire de Co2-humidite-N2, 5A, permet de predire de maniere satisfaisante les resultats experimentaux pour l'adsorption simultanee du CO2 et de l'humidite dans un lit fixe. L'humidite etant le composant fortement adsorbe force le dioxyde de carbone (composant faiblement adsorbe) a retourner. Les proprietes thermophysiques et de transport gouvernent principalement la dynamique du procede, dont le controle ou la manipulation pourrait donner une meilleure separation par adsorption d'un composant a partir d'un autre dans un meme courant. Les principaux parametres sont la concentration d'adsorbat a l'entree, le nombre de Reynolds des particules, le rapport entre le diametre et la longueur de lit, le nombre de Schmidt, le coefficient de distribution d'equilibre, le nombre de Sherwood et le nombre de Kutateladze.

Arecoline is an alkaloid of betel nut of Areca catechu. Betel nut is chewed by millions of people in the world and it causes oral and hepatic cancers in human. It has therapeutic value for the treatment of Alzheimer and schizophrenia. Arecoline has immunosuppressive, mutagenic and genotoxic effects in laboratory animals. It also affects endocrine functions. The objective of this study was to investigate the effects of arecoline on pineal-testicular axis in rats. Since pineal activity is different between day and night, the current study is undertaken in both the photophase and scotophase. The findings were evaluated by ultrastructural and hormonal studies of pineal and testicular Leydig cells, with quantitations of fructose and sialic acid of sex accessories. Arecoline treatment (10 mg/kg body weight daily for 10 days) caused suppression of pineal activity at ultrastructural level by showing dilatation of the cisternae of the rough endoplasmic reticulum (RER), large autophagosome-like bodies with swollen mitochondrial cristae, numerous lysosomes, degenerated synaptic ribbons and reduced number of synaptic-like microvesicles. Moreover, pineal and serum N-acetylserotonin and melatonin levels were decreased with increased serotonin levels in both the gland and serum. In contrast, testicular Leydig cell activity was stimulated with abundance of smooth endoplasmic reticulum (SER), electron-dense core vesicles and vacuolated secretory vesicles, and increased testosterone level in the arecoline recipients. Consequently, the testosterone target, like prostate, was ultrastructurally stimulated with abundance of RER and accumulation of secretory vesicles. Fructose and sialic acid concentrations were also significantly increased respectively in the coagulating gland and seminal vesicle. These results were more significant in the scotophase than the photophase. The findings suggest that arecoline inhibits pineal activity, but stimulates testicular function (testosterone level) and its target organs presumably via muscarinic cholinergic receptor in rats.

Experimental data for the simultaneous adsorption of CO2 and moisture with variations of some process variables, such as inlet adsorbate concentration, particle Reynolds number, and bed diameter to bed length ratio, have been generated to see their effects on the efficiency of adsorption of CO2 and moisture. Presence of moisture strongly affects the CO2 adsorption behaviour leading to roll up of CO2 concentration breakthrough curves, whereas the presence of CO2 has an insignificant effect on the moisture adsorption behaviour. Des donnees experimentales d'adsorption simultanee de CO2 et d'humidite avec des variations de certaines variables de procede, tels la concentration d'adsorbat, le nombre de Reynolds des particules et le rapport entre le diameatre et la hauteur du lit, ont ete produites afin de voir leurs effets sur l'efficacite d'adsorption du CO2 et de l'humidite. La presence d'humidite influe fortement sur le comportement d'adsorption de CO2, ce qui donne des courbes de transition en forme de rouleaux pour la concentration de CO2, tandis que la presence de CO2 a un effet negligeable sur l'adsorption de l'humidite.

Investigations were carried out to find out the role of higher and lower ambient temperatures together with short and long photoperiods on ovarian growth and secretion of steroids (estradiol-17 beta and progesterone) in the adult female soft-shelled turtle Lissemys punctata punctata during the preparatory, recrudescent, and quiescent phases of its seasonal reproductive cycle. In each phase, females were treated with 3 degrees C higher and 3 degrees C lower than the mean highest and lowest ambient temperatures in association with short and long photoperiods for short-term (4 week) and long-term (8 weeks or more) durations. Short-term high-temperature treatment significantly stimulated ovarian growth and secretion of estradiol-17 beta during the preparatory phase. Eight-week treatment failed to exercise further stimulation over 4-week treatment, whereas 10-week treatment caused regressive changes of ovary (atresia of follicles). Both short- and long-term high-temperature treatments caused degeneration of ovarian follicles during the recrudescent phase. Low-temperature treatment slowed down ovarian growth and secretion in both the preparatory and recrudescent phases. In the quiescent phase, low- as well as high-temperature treatments exercised little influence over the refractory ovarian growth and secretion. Photoperiod appeared to have no effect on female reproduction in any phase. Thus, high temperature is suggested to have a triggering role on ovarian growth and secretion of estrogen at the early preparatory phase, but once the ovarian function sets in, high temperature seems to have a regressive rather than stimulatory effect on ovarian growth and function.

The course and kinetics of nonisothermal bulk polymerization of multifunctional acrylates were studied by dynamic differential scanning calorimetry (DSC). Measurements were carried out for four straight-chain monomers, diethylene glycol diacrylate (DEGDA), triethylene glycol diacrylate (TEGDA), tetraethylene glycol diacrylate (TTGDA), and poly(ethylene glycol)diacrylate (PEGDA) (mol. wt. 600), to study the effect of the backbone chain length, atmosphere, and type of initiator on the crosslinking kinetics. 4,4′-Azobis(4-cyanovaleric acid) (1.0%, w/w) was used as a free-radical initiator. From the dynamic scanning of polymerization of DEGDA at five heating rates (2–30°C/min), the average heat of polymerization (ΔHp) was found to be 524.2 J/g. An activation energy of 108.8 kJ/mol and preexponential factor 5.34 × 1012 s−1 were obtained from the Arrhenius plot, In dα/dt. The rate of polymerization was found manyfold greater at 20–60% conversion than at the initial stage (2–8% conversion). Polymerization was studied under both nitrogen and air atmosphere. The results corresponded well with the theory of oxygen inhibition. Different types of initiators, e.g., 4,4′-azobis(4-cyanovaleric acid) (ABCVA), 2,2′-azobisisobutyronitrile (AIBN), and benzoyl peroxide (BPO) were used for polymerization and ABCVA was found to be the most efficient among all. © 1995 John Wiley & Sons, Inc.

Scanning electron and light microscopic studies reveal significant changes in the endometrial histophysiology of the soft-shelled turtle Lissemys punctata punctata during its seasonal reproductive cycle. Scanning electron microscopy shows the entire oviductal mucosa to be only slightly folded throughout the non-breeding period (regressive, quiescent, preparatory and recrudescent phases). With the onset of the breeding phase, the mucosa shows extensive foldings and convolutions. The adluminal mucosal lining of the non-breeding oviduct is covered by a tall, dense ciliary bed, interrupted by a few fissures and pits. Microvilli-bordered secretory cells only appear amongst the ciliated cells during the breeding phase. Light microscopic study reveals the mucosal epithelium to be low pseudostratified columnar throghout the non-breeding period. The breeding epithelium, on the other hand, is tall columnar and does contain clearly distinguishable ciliated and secretory cell types. Submucosal glands only appear for a short period (ovulation to oviposition) in the infundibulum and isthmus regions of the oviduct, but these glands are observed throughout the reproductive cycle in the tube and uterus. The secretory activity of the submucosal glands, which occur only during the peak breeding stages, involves release of vesicular secretory materials through the gland openings. The stimulated endometrial histology and activity during the breeding phase coincide with increased levels of serum estrogen and progesterone, whereas the regressed and inactive state of the endometrium is paralleled by decreased levels of these ovarian steroids. © 1995 Wiley-Liss, Inc.

In the presence of excess hydrogen peroxide and formic acid the latex stage epoxidation of natural rubber is pseudo–first order in nature. A kinetic model is developed to predict the maximum extent of epoxidation for the reaction system and its variation with increasing acid concentration. Th dependence of the overall rate constant on acid concentration is also studied.

Study of the oviduct of the pied myna (Sturnus contra contra) throughout the year reveals that oviductal weight, length, surface epithelial height and glycogen content are low during August to January (nonbreeding phase), partially increase during February to April (pre-breeding phase), maximally increase in May (breeding phase) and decrease in June and July (post-breeding phase). In the nesting cycle, there is greatest growth in all the regions of the oviduct from early nest-building to the egg-laying period and this is followed by rapid involution during incubation and nestling periods. Some notable features in the oviduct of the pied myna are described: 1) All five regions of the oviduct (infundibulum, magnum, isthmus, uterus, and vagina) are clearly distinguishable when studied from serial sections of the oviduct even during the nonbreeding phase of the annual ovarian cycle. 2) There is a strong correlation between initiation of tubular gland formation and the onset of nestbuilding activity. 3) The distal part of the magnum is differentiated into a 'mucous region' having well developed basal nonciliated cells. 4) A sixth zone can be identified between the magnum and isthmus. Sperm hostlike glands exist at the cranial end of the zone. 5) Several circular epithelial invaginations are evident in the intermucosal folds and their size decreases in centripetal order in the vagina. 6) The pattern and degree of regression are different in various regions of the oviduct. A close synchrony between ovarian and oviducal cycles is indicated in the pied myna (Sturnus contra contra).

Atretic follicles of the ovary of the Indian pied myna (Sturnus contra contra) were studied in birds collected each month throughout the year. Histological examination included histochemical techniques for 3β-hydroxy-steroid dehydrogenase (3β-HSDH) and for lipids. Atretic follicles were mainly of two types: nonbursting (lipoidal and cystic) and bursting (Types I-VI). Nonbursting atresia was observed in the smaller follicles (500 μm in diameter), whereas larger follicles (500 μm in diameter, viz., small developing, large developing, and yolky follicles) showed exclusively a bursting type of atresia. Sudanophilic lipid was found in both types (lipoidal and cystic) of nonbursting atresia, but was present only in early stages of bursting atresia. Activity of 3β-HSDH was absent in nonbursting atresia, but present in early stage of bursting atresia. Nonbursting atresia was common throughout the year and higher in frequency than the bursting type. Bursting atresia was common during March through May and attained its peak level during the nesting cycle.