Bisfosfonatos: síntese, análises químicas e aplicações farmacológicas

Bisphosphonates are drugs that have been widely used in different bone diseases, and have recently been used successfully against many parasites. Various synthetic routes to prepare different types of bisphosphonates have been described, with distinct potency and pharmacological activity. A number of analytical techniques are currently being used to analyze these drugs; among these, the high performance liquid chromatography (HPLC), with different systems of detection, is worth highlighting. However, the development of more sensitive methods is still necessary, once they are essential for bioavailability and bioequivalence studies. This paper reports the major synthesis routes, chemical analysis methodologies and pharmacological applications of bisphosphonates.

Crustacean and aquatic insect assemblages in the Mediterranean coastal ecosystems of Empord`a wetlands (NE Iberian peninsula)

Coastal wetlands are characterized by high biodiversity, which is one of the main criteria considered when establishing protection policies or when proposing adequate management actions. In this study, the crustacean and aquatic insect composition of the Empord`a wetlands is described. These two faunal groups contribute highly to the total biodiversity in these wetlands but are seldom considered when managing natural areas. A selection (84 sampling points) of all water body types present in the Empord`a wetlands were sampled monthly (surber and dip net with a 250 μm mesh). Sampling was carried out during 3 surveys (1991-92, 1996-97 and 1999-2000). A rich fauna of 125 crustacean and 295 aquatic insect taxa was identified. We characterized each water body type using the most abundant species and the relative species richness of the taxonomic groups. A classification of the water body types, according to similarity between inventories, groups the brackish and hyperhaline systems in one cluster and the various freshwater systems in another one. Among freshwater systems, lotic waters and freshwater wetlands have a high similarity, whereas rice fields and freshwater springs have a low similarity

Metodologías de enseñanza y aprendizaje reflexivos en la universidad. Una investigación centrada en la percepción de estudiantes de grado de la Universidad de Girona

The aim of the research presented in this article is to understand undergraduate students’ appraisal of the influence of reflective learning methodology in different aspects of their learning, and to obtain evidence of the main difficulties encountered by students and the main contributions of this kind of methodology into their learning process. The study was conducted in four different degree courses (Social education, Environmental sciences, Nursing, and Psychology) at the University of Girona Through the development of a self-report reflective learning questionnaire and its application to 162 students who participated in the experiences, we conclude that reflective learning can be positively assessed as having great potential to train university undergraduates

Uso de artigos científicos em uma disciplina de Físico-Química

This paper describes the use of primary chemistry literature in a fifth-semester physical chemistry course for undergraduate chemistry students. The main goal is to expose students to the primary literature of physical chemistry, demonstrating how they can benefit from using it. The assignment addresses issues in chemical education such as scientific writing, relating lecture material to the real world, and conducting literature searches. The student evaluation of this assignment, consisting of two surveys and one focus group, showed its usefulness. The details of the evaluation instruments and their results are provided. Out of 45 students enrolled in the course, 30 (67%) students completed the assignment.

Carotenoids production: microorganisms as source of natural dyes

Carotenoids are natural dyes synthesized by plants, algae and microorganisms. Application in many sectors can be found, as food dyeing and supplementation, pharmaceuticals, cosmetics and animal feed. Recent investigations have shown their ability to reduce the risks for many degenerative diseases like cancer, heart diseases, cataract and macular degeneration. An advantage of microbial carotenoids is the fact that the cultivation in controlled conditions is not dependent of climate, season or soil composition. In this review the advances in bio-production of carotenoids are presented, discussing the main factors that influence the microbial production of these dyes in different systems.

Quantificação dos isômeros ácido L-ascórbico e ácido D-iso-ascórbico em geleias de frutas por cromatografia líquida de alta eficiência

Ascorbic acid has important nutritional characteristics such as high antioxidant potential, preventing diverse damage and diseases in the tissues and the process of aging. Different isomeric forms of the ascorbic acid can be found in nature and each one have different potential antioxidant and different activity pro-vitamin C. This work examined a method to detect and quantify the isomers L-ascorbic acid (LAA) and D-iso-ascorbic acid (DIAA) in jelly fruit. The method showed acceptable selectivity, linearity, repeatability and recovery. DIAA was not found in the analyzed samples, but LAA was found up to 605 mg in 100 g of sample.

Constituintes químicos dos galhos de Simaba guianensis subesp. ecaudata (Cronquist)

Simaba guianensis subesp. ecaudata (Simaroubaceae) is a tree found in the Brazilian Amazon. This work describes for the first time the fractionation of stems of this species that resulted in the isolation of the cytotoxic triterpene piscidinol A, the alkaloid 9-methoxycanthin-6-one, caryophyllene oxide, also isolated for the first time from this species and a new alkaloid (6-methoxy-(9H-β-carbolin-1-il)-(Z)-2-propenoic acid). Quantification of 9-methoxycanthin-6-one in different extracts and fractions of stems of S. guianensis by high performance liquid chromatography was also performed. The concentration of 9-methoxycanthin-6-one in methanolic and aqueous extracts were inferior to the known cytotoxic concentration of this compound.

CASOS INVESTIGATIVOS E A RELAÇÃO COM O SABER: TRAJETÓRIA E PROCESSO DE APRENDIZAGEM DE ESTUDANTES DO ENSINO SUPERIOR NO TOCANTINS

In light of the theory of relationship with know of Bernard Charlot, aiming to understand the unique stories of the subject through a positive lecture, i.e., understanding the reality and the way the subjects read and interpret the world, this article attempts identify how higher education students solve an investigative case and learn the scientific knowledge using this theory. For this, we used narrative as a discourse genre to collect the data of 34 students who participated in the small group activities. After content analysis, the results showed that all groups of students solve the case in a similar way and in three stages, prevailing relations with know with the world, with others and with yourself. However, even if the resolution is similar, chemical learning differs between different groups and differs between the scientific content present in the case. From these results it is possible to identify the effectiveness of learning depends on the epistemic and identity relationships with know of each subject (relationship with yourself) because to learn the student must enter into an intellectual activity (investigative case), stay on it and develop the relationships with known necessary to master the normativity (chemical language).

Pientalon lämmitysjärjestelmän valinta

Lämmityskustannukset ovat merkittävä osa pientalon asumiskustannuksista. Oikealla lämmitysratkaisuvalinnalla voidaan saada merkittäviä säästöjä aikaiseksi. Lämmitysjärjestelmä on pitkäaikainen investointi ja järjestelmän vaihtaminen toiseen on usein kallista. Järjestelmän valinnassa tehtyä virhettä on siten vaikea korjata jälkikäteen. Jotta osataan valita kuhunkin tilanteeseen sopivin lämmitysratkaisu, täytyy tietää millaisia kustannuseriä eri vaihtoehdot sisältävät ja millainen merkitys niillä on kokonaiskustannuksiin. Lämmitysjärjestelmän valinnassa tulee huomioida asuntojen erilaiset energiantarpeet, tekniset ratkaisut ja käyttäjien mieltymykset. Edellä mainituista syistä lämmitysjärjestelmiä ei voida laittaa yleispätevään edullisuusjärjestykseen. Tässä työssä käsitellään esimerkkilaskelmien avulla joitain lämmitysjärjestelmäratkaisuja ja niiden kustannuksia. Vaikka työ ei käsitä kaikkia markkinoilla olevia vaihtoehtoja, työssä esitettyjä laskentamenetelmiä voidaan soveltaa myös muihin lämmitysjärjestelmiin.

Tiedon hallinta varastonhallintajärjestelmän hankinnassa

Diplomityössä toteutettiin varastonhallintajärjestelmän hankinta prosessoimalla tietoa hallitusti varastonhallinnan kehittämiseksi. Kvalitatiivinen tapaustutkimus tehtiin tietojohtamisen näkökulmasta käyttäjälähtöisen C-CEI –menetelmän avulla haastattelemalla ja havainnoimalla tapausyritystä. Haastatteluja tehtiin 10 kertaa. Tutkimuksessa kartoitettiin ja kilpailutettiin kotimaiset järjestelmätoimittajat, joita löydettiin 15. Näistä toimittajista 6 vastasi vaatimuksia ja teki tarjouksen. Tutkimuksen lopuksi tehtiin järjestelmän hankintaehdotus. Tutkimuksen teoreettinen viitekehys koostui tietojohtamisesta, varastonhallinnasta ja ohjelmistotuotannosta. Tutkimuksessa pääkysymyksenä esitettiin miten tietojohtamisen avulla voidaan tukea varastonhallintajärjestelmän hankintaa. Tutkimuksessa havaittiin, että tietojärjestelmän hankinta varastonhallinnan osalta on moniulotteinen liiketoiminnan kehittämistehtävä. Tietojärjestelmähankinta tulisi siten nähdä liiketoimintaa eteenpäin vievänä mahdollisuutena. Lisäksi loppukäyttäjän vaatimusten kartoittamiseen tulisi sitoutua huolella ja suhtautua kriittisesti eri järjestelmävaihtoehtoihin. Vaatimusmäärittelyn asettaminen ja vaatimusten priorisoiminen ovat haasteellisia tehtäviä. Tiedon hallinnan aikana saatiin selville, että loppukäyttäjän vaatimusten mukainen tarjouspyyntö edesauttaa ensinnäkin tarjousten tekemistä mutta myös niiden prosessointia ja analysointia. Vain oikealla tiedolla ja sen yhteyksillä on merkitystä. Tutkimuksen perusteella tietojärjestelmän hankinta suositellaan tehtäväksi hallitsemalla tietoa systemaattisesti erityisesti sen alkuvaiheen aikana. Tietojohtaminen virtaviivaistaa hankkeen etenemistä ja aikataulutusta, vähentää loppukäyttäjän kustannuksia tehokkaalla kilpailutusmenettelyllä, edistää kilpailukykyä ja luo hyvän lähtökohdan koko tietojärjestelmän hankinnan läpiviemiselle ja yhteistyö-suhteen rakentumiselle kauppakumppaneiden välille.

EDTA- and DTPA-functionalized silica gel and chitosan adsorbents for the removal of heavy metals from aqueous solutions

Adsorbents functionalized with chelating agents are effective in removal of heavy metals from aqueous solutions. Important properties of such adsorbents are high binding affinity as well as regenerability. In this study, aminopolycarboxylic acid, EDTA and DTPA, were immobilized on the surface of silica gel, chitosan, and their hybrid materials to achieve chelating adsorbents for heavy metals such as Co(II), Ni(II), Cd(II), and Pb(II). New knowledge about the adsorption properties of EDTA- and DTPA-functionalizedadsorbents was obtained. Experimental work showed the effectiveness, regenerability, and stability of the studied adsorbents. Both advantages and disadvantages of the adsorbents were evaluated. For example, the EDTA-functionalized chitosan-silica hybrid materials combined the benefits of the silica gel and chitosan while at the same time diminishing their observed drawbacks. Modeling of adsorption kinetics and isotherms is an important step in design process. Therefore, several kinetic and isotherm models were introduced and applied in this work. Important aspects such as effect of error function, data range, initial guess values, and linearization were discussed and investigated. The selection of the most suitable model was conducted by comparing the experimental and simulated data as well as evaluating the correspondence between the theory behind the model and properties of the adsorbent. In addition, modeling of two-component data was conducted using various extended isotherms. Modeling results for both one- and twocomponent systems supported each other. Finally, application testing of EDTA- and DTPA-functionalized adsorbents was conducted. The most important result was the applicability of DTPA-functionalized silica gel and chitosan in the capturing of Co(II) from its aqueous EDTA-chelate. Moreover, these adsorbents were efficient in various solution matrices. In addition, separation of Ni(II) from Co(II) and Ni(II) and Pb(II) from Co(II) and Cd(II) was observed in two- and multimetal systems. Lastly, prior to their analysis, EDTA- and DTPA-functionalized silica gels were successfully used to preconcentrate metal ions from both pure and salty waters

The effect of wood supply and bleaching process on pulp brightness stability

One hundred different 5.5-year-old Eucalyptus grandis x Eucalyptus urophylla wood clones were cooked to kappa number 15-17.5 and the resulting kraft pulps oxygen-delignified to kappa 9.5-11.5 under fixed conditions, except for chemical charges. Thirteen samples showing large variations in effective alkali requirement, pulp yield and O-stage efficiency and selectivity were selected for brightness reversion studies. These samples were bleached to 90-91% ISO by DEDD and DEDP sequences and their brightness stability and chemical characteristics determined. Heat reversion of the eucalyptus kraft pulps was strongly influenced by the wood supply, with brightness loss varying in the range of 2.1-3.6 and 0.8-1.7 %ISO for ODEDD and ODEDP bleached pulps, respectively. Pulps bleached by the ODEDP sequence showed reversion values 1.3-1.9 % ISO lower than those bleached by the ODEDD sequence. Pulp carbonyl content decreased by 35-40% during the final peroxide bleaching stage. Carbonyl and carboxyl groups correlated positively with brightness reversion, as did permanganate number and acid soluble lignin. Pulp final viscosity and metal and DCM extractives contents showed no significant correlation with brightness reversion. Pulping, oxygen delignification and ECF bleaching performances also showed no correlation with brightness reversion.

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Comparison of metering mechanisms of corn seed

It was compared the performance of the metering mechanism of corn seeds (Zea mays) in direct seeding in an area of ​​200 ha, a property in Piraí do Sul, State of Paraná - PR, in Brazil. It was seeded 4 maize hybrids, 50 ha of each, with seeds of different sieves. The experiment was conducted in a randomized block design (RBD), with 3 treatments and 9 repetitions for each corn hybrid. The treatments were the pneumatic seed of metering mechanisms, horizontal perforated disc with and without ramp®. The plots were 40 m² and were distributed at the early, middle and late sowing. The variables analyzed in each corn hybrid were initial population, faulty spacing, multiple spacing, acceptable spacing, and yield components. As there were no significant differences in the variables, it was concluded that the quality of seeding with different systems of distribution was similar in the different sieves of distributed corn seeds.