Tratamiento de las aguas residuales provenientes de la industria de medicamentos

El principal problema que se presenta en la industria farmacéutica actual es la carencia de soluciones tecnológicas nacionales para el tratamiento de los residuos líquidos. Diversas producciones de medicamentos novedosos y de avanzada generan aguas residuales no caracterizadas ni evaluadas anteriormente por algún proceso. La disposición de ellas produce serios impactos en los recursos hídricos, con incumplimiento de las regulaciones y normas ambientales vigentes. Los antibióticos pertenecen al grupo de medicamentos que han sido detectados en lagos y corrientes de diferentes partes del mundo y la presencia de estos compuestos en el ambiente ha provocado el aumento de la toxicidad de los organismos acuáticos y el surgimiento de especies de bacterias con resistencia antibiótica. Se cuenta con una base de datos de los diversos vertimientos de más de 15 centros de producción de medicamentos. Las tecnologías desarrolladas basadas en los tratamientos de película fija anaerobios y aerobios, así como la aplicación del ozono, fueron efectivas

Mechanical Bonds and Topological Effects in Radical Dimer Stabilization

While mechanical bonding stabilizes tetrathiafulvalene (TTF) radical dimers, the question arises: what role does topology play in catenanes containing TTF units? Here, we report how topology, together with mechanical bonding, in isomeric [3]- and doubly interlocked [2]catenanes controls the formation of TTF radical dimers within their structural frameworks, including a ring-in-ring complex (formed between an organoplatinum square and a {2+2} macrocyclic polyether containing two 1,5-dioxynaphthalene (DNP) and two TTF units) that is topologically isomeric with the doubly interlocked [2]catenane. The separate TTF units in the two {1+1} macrocycles (each containing also one DNP unit) of the isomeric [3]catenane exhibit slightly different redox properties compared with those in the {2+2} macrocycle present in the [2]catenane, while comparison with its topological isomer reveals substantially different redox behavior. Although the stabilities of the mixed-valence (TTF2)^(•+) dimers are similar in the two catenanes, the radical cationic (TTF^(•+))_2 dimer in the [2]catenane occurs only fleetingly compared with its prominent existence in the [3]catenane, while both dimers are absent altogether in the ring-in-ring complex. The electrochemical behavior of these three radically configurable isomers demonstrates that a fundamental relationship exists between topology and redox properties

Meso- and macrozooplankton communities in the Weddell Sea, Antarctica

The present paper describes composition and abundance of meso- and macrozooplankton in the epipelagic zone of the Weddell Sea and gives a systematic review of encountered species regarding results of earlier expeditions. Material was sampled from 6 February to 10 March 1983 from RV Polarstern with a RMT 1+8 m (320 and 4500 μm mesh size). In agreement with topography and water mass distribution three distinct communities were defined, clearly separated by cluster analysis: The Southern Shelf Community has lowest abundances (approx. 9000 ind./1000 m3). Euphausia crystallorophias and Metridia gerlachei are predominating. Compared with the low overall abundance the number of regularly occurring species is high (55) due to many neritic forms. Herbivores and omnivores are dominating (58% and 35%). The North-eastern Shelf Community has highest abundances (about 31 000 ind./1000 m3). It is predominated by copepodites I–III of Calanus propinquus and Calanoides acutus (61%). The faunal composition is characterized by both oceanic and neritic species (64). Fine-filter feeders are prevailing (65%). The Oceanic Community has a mean abundance of approximately 23 000 ind./1000 m3, consisting of 61 species. Dominances are not as pronounced as in the shelf communities. Apart from abundant species like Calanus propinquus, Calanoides acutus, Metridia gerlachei, Oithona spp. and Oncaea spp. many typical inhabitants of the Eastwind Drift are encountered. All feeding types have about the same importance in the Oceanic Community

CHANGES IN PLASMA PROGESTERONE AND ESTRADIOL DURING NATURAL PROSTAGLANDIN F2a-INDUCED PARTURITION IN THE RABBIT

[EN] The influence of administration of natural prostaglandin F2a (PgF) on plasma progesterone (P4) and estradiol-17(l (E2) levels during the last days of pregnancy (days 29-32) was studied in 13 doe rabbits of the California x New Zealand White breed. Animals were allocated to receive either a single intramuscular injection of 800 or 1200μg of natural PgF on day 29 of pregnancy at 10 h (treated groups) or no injection (control group). AH does treated with PgF kindled within 60 h after injection, whereas the variation in birth time in control group was greater (79.2 ± 8.9 h). No influence of the prostaglandin treatment on mean plasma estradiol (5.2 pg/ml) and both litter size and born dead (7.2 ± 0.7 and 0.4 ± 0.6, respectively) was observed. A significant fall in progesterone concentration was defected in treated animals at 20 h on day 29 compared with control group (3.17 ± 0.22 and 3.47 ± 0.32 vs. 6.7 ± 1.4 ng/ml; P<0.05). Our results suggest that the induction of parturition with natural PgF has similar effects on plasma P4 levels and in synchronization of parturitions to synthetic analogues, although the dose administered is greater.[FR] L'inf/uence de f'administration de prostag/andine naturel/e F2a (PgF) sur le taux de progestérone (P4) et d'estradiol-17b (E2) plasmatique durant les demiers jours de la gestatlon (29-32 jours) a été étudié sur 13 tapines de race Calífomien x NZW Les animaux ont été répartis en trois lots, deux recevant une seule injection intramusculaire de 800 ou 1200 μg de PgF naturel/e, él 1 O heures, au 29eme jour de gestation, l'autre ne recevant aucune injection (lot contr61e). Toutes les lapines traitées avec PgF ont mis bas enviran 60 heures aprés l'injection, tandis que pour ce/les du groupe contr61e le moment de la mise bas a été plus variable: 79,2 ± 8,9 heures. Le traitement par la prostaglandine n'a pas eu d'influence sur le taux mayen d'CBstradiol plasmatique (5,2 pglml) ni sur la taille de la portée ou le nombre de mort-nés (7,2 ± O, 7 et 0.4 ± 0,6, respectivement). une chute significative de la concentration en progestérone, par rapport au groupe controle, a été observée chez les animaux traités él 20 heures au 29eme jour (3, 17 ±0,22 et 3.47 ± 0,32 vs 6,7 ± 1,4 ng/ml, P<0,05). Nos résultats suggerent que l'induction de la mise bas avec PgF naturel/e a des effets sur les taux de P 4 plasmatique et sur la synchronisation des mises-bas similaires él ceux de la mame molécule synthétique, bien que la dose administrée soit supérieure.Rebollar, P.; Alvariño, J.; Illera, J.; Silvan, C.; Lorenzo, P. (1997). CHANGES IN PLASMA PROGESTERONE AND ESTRADIOL DURING NATURAL PROSTAGLANDIN F2a-INDUCED PARTURITION IN THE RABBIT. World Rabbit Science. doi:10.4995/wrs.1997.312SWORD05

Quasiclassical trajectory calculations of the thermal rate coefficient for the oxygen atom + hydroxyl .fwdarw. oxygen + hydrogen atom reaction on realistic double many-body expansion potential energy surfaces for ground-state hydroperoxy

Quasi-classical trajectory calculations of the thermal rate coefficient for the title reaction have been carried out over the temperature range 250 5 T 5 2500 K by using two recently reported DMBE potential energy surfaces for the ground state of the hydroperoxyl radical. The results are compared with each other and with experiment. The agreement is god. Our results support previous theoretical calculations by Miller on the Melius-Blint potential energy surface in that nonstatistical ‘recrossing” effects are very important. For the DMBE I1 (DMBE 111) potential energy surface, these nonstatistical corrections are found to increase from a factor of about 1.2 (1.4) at 250 K to about 2.1 (2.5) at 2500 K. However, they are considerably smaller than the nonstatistical corrections reported by Miller (factors of about 2.2 and 3.3 at the above temperatures). Although due, of course, to topographical differences between the DMBE and Melius-Blint potential energy surfaces, such discrepancy stems also from the different definitions used for H02* complex in the simple chemical model 0 + OH e H02* -+ 0 2 + H