Estudo do poder germinativo da semente de manga

The author studied the storage of seeds of mango trees with the aim of Keeping high its ability of germination. Seven means of storage were tried, with two temperatures: environment temperature (22 to 27 degrees Centigrade) and cold store room (5 degrees centigrade). The methods of storage tried were: 1 - The frewit kept complete. 2 - Seeds taken within the stone. 3 - Seeds taken out of the stone. 4 - Stones heated with a Fungicida (Zineb). 5 - Stones cut laterally and heated with a fungicide (Zineb). 6 - Seeds (out of sones) heated with Zineb. 7 - Stones steatified with sand. The best results were obtained for seeds kept within whole fruits, probably owing to protection provided by outer layers. The use of fungicide imposed the sanitary aspect of seeds and stones. Storage in cold store room (5 degrees Centigrade) injured the seeds and stones in all cases. Germinating power was kept high up to 70 days for complete fruits. It seems that biggers fruits were more favorable to keep high the ability of theirs seeds to germinate.

Morfología del aparato digestivo de Enteroctopus megalocyathus y Loligo sanpaulensis (Mollusca, Cephalopoda)

A detailed description of the morphology of the digestive organs of Enteroctopus megalocyathus (Gould, 1852) and Loligo sanpaulensis Brakoniecki, 1984 is given. The mandibles, the crop diverticulum, a doubly coiled caecum, the loop of the medium intestine and the appendages of the digestive gland are first described for E. megalocyathus. The most outstanding finding in L. sanpaulensis is the location of the single posterior salivary gland, wholly embedded in the digestive gland.

Stoneflies from the Philippines (Plecoptera)

v.42:no.6(1958)

Aspectos parasitários observados no local inoculado com esporozoitos de Plasmodium Gallinaceum

The following is a summary of the studies made on the development of Plasmodium gallinaceum sporozoites inoculated into normal chicks. Initially large numbers of laboratory reared Aëdes aegypti were fed on pullets heavily infected with gametocytes. Following the infectious meal the mosquitoes were kept on a diet of sugar and water syrup until the appearance of the sporozoites in the salivary glands. Normal chicks kept in hematophagous arthropod proof cages were then inoculated either by bite of the infected mosquitoes or by subcutaneous inoculations of salivary gland suspensions. By the first method ten mosquitoes fed to engorgement on each normal chick and were then sacrificed immediately afterwards to determine the sporozoite count. By the second method five pairs of salivary glands were dissected out at room temperature, triturated in physiological saline and inoculated subcutaneously. The epidermis and dermis at the site of inoculation were excised from six hours after inoculation to forty eight hours after appearance of the parasites in the blood stream and stretched out on filter paper with the epithelial surface downward. The dermis was then curretted. Slides were made of the scrapings consisting of connective tissue and epithelial cells of the basal layers which were fixed by metyl alcohol and stained with Giemsa for examination under the oil immersion lens. Skin fragments removed from normal chicks and from regions other than the site of inoculation in the infected chicks were used as controls. In these, only the normal histological aspect was ever encountered. In the biopsy made at the earliest period following inoculation clearly defined elongated forms with eight or more chromatin granules arranged in rosary formation were found. The author believes these to be products of the sporozoite evolution. Search for transition stages between these forms and sporozoites is planned in biopsies to be taken immediately following inoculation and at given intervals up to the six hour period. 1.) 6 and 12 hour periods. The bodies referred to above found in the first period in great abundance, apparently in proportion to the large numbers of sporozoites inoculated, were perceptibly reduced in numbers in the second period. 2.) 18 hour period. Only one biopsy was examined. This presented a binuclear body shown in Fig. 1, having a more or less hyaline protoplasm staining an intense blue and a narrow vacuole delimiting the cell boundaries. The two chromatin grains were quite large presenting a clearly defined nuclear texture. 3.) 24 hour period. A similar body to that above (Fig. 2) was seen in the only preparation examined. 4.) 60 hour period. The exoerythrocytic schizonts were found more frequently from this period onward. Several such were found no longer to contain the previously described vacuoles (Fig. 3). 5.) 84 hour period. Cells bearing eight or more schizonts were frequently encountered here. That these are apparently not bodies in process of division may be seen in Fig. 4. From this time onward small violet granules similar to volutine grains appeared constantly in the schizont nucleus and protoplasm. These are definitely not hemozoin. The above observations fell within the incubation period as repeated examinations of the peripheral and visceral blood were negative. Exoery-throcytic parasites also were never encountered in the viscera at this time. Exoerythrocytic schizonts searched for at site of inoculation 1, 24 and 48 hours after the incubation period were present in large number at all three times with apparent tendency to diminish as the number within the blood stream increased. Many of them presented the violet granules mentioned above. The appearance of the chromatin and the intensity of staining of the protoplasm varied from body to body which doubtless corresponds to the evolutionary stage of each. This diversity of aspect may frequently be seen in the parasites of the same host cell (Fig. 5.). These findings lend substance to the theory that the exoerythrocytic forms are the link between the sporozoites and the pigmented parasites of the red blood corpuscles. The explanation of their continued presence in the organism after infection of the blood stream takes place and their presence in cases infected by the inoculation blood does not come within the scope of this work. Large scale observations shortly to be undertaken will be reported in more detail particularly observations on the first evolutionary phases of the sporozoite within the organism of the vertebrate host.

Distribuição geográfica da fauna e flora da Baía de Guanabara

The author studied, the horizontal and vertical distribution of most common part of the flora and fauna of the bay of Guanabara at Rio de Janeiro. In this paper the eulittoral, poly, meso and oligohaline regions were localised and studied; and the first chart of its distribution was presented (fig. 2). The salinity of superficial waters was established through determinations based on 30 trips inside the buy for collecting biological materials. Some often 409 determinations which were previous reported together with the present ones served for the eleboration of a salinity map of the bay of Guanabara (fig. 1). This map of fig. 2 shows the geographic locations of the water regions. EULITTORAL WATER REGIME — Fig. 3 shows the diagram scheme of fauna and flora of this regime. Sea water salinity 34/1.000, density mean 1.027, transparent greenish waters, sea coast with moderate bursting waves. Limpid sea shore with white sand, gneiss with the big barnacle Tetraclita squamosa var. stalactifera (Lam. Pilsbry. Vertical distributions: barna¬cles layers with a green region in which are present the oyster Ostrea pa-rasitica L., the barnacles Tetraclita, Chthamalus, Balanus tintinnabulum var. tintinnabulum (L.) e var. antillensis Pilsbry in connection with several mollusca and the sea beatle Isopoda Lygia sp. Covered by water and exposed to air by the tidal ritms, there is a stratum of brown animals that is the layer of mussels Mytilus perna L., with others brown and chestnut animals : the Crustacea Pachygrapsus, the little crab Porcellana sp., the stone crab Me-nippe nodifrons Stimpson, the sea stars Echinaster brasiliensis (Mull. & Tr.), Astropecten sp. and the sea anemones Actinia sp. Underneath and never visible there is a subtidal region with green tubular algae of genus Codium and amidst its bunches the sea urchin Lycthchinus variegatus (Agass.) walks and more deeply there are numerous sand-dollars Encope emarginata (Leske). The microplancton of this regime is Ceratiumplancton. POLYHALINE WATER REGIMB — Water almost sea water, but directly influenced by continental lands, with rock salts dissolved and in suspension. Salinity: 33 to 32/1.000. This waters endure the actions of the popular nicknamed «water of the hill» (as the waters of mesohaline and oligohaline regimes), becoming suddenly reddish during several hours. That pheno¬menon returns several times in the year and come with great mortality of fishes. In these waters, according to Dr. J. G. FARIA there are species of Protozoa : Peridinea, the Glenoidinium trochoideum St., followed by its satellites which he thinks that they are able to secret toxical substances which can slaughter some species of fishes. In these «waters of the hill» was found a species of Copepoda the Charlesia darwini. In August 1946 the west shore of the Guanabara was plenty of killed fishes occupying a area of 8 feet large by 3 nautical miles of lenght. The enclosure for catching fishes in the rivers mouthes presents in these periods mass dead fishes. The phenomenon of «waters of the hill» appears with the first rains after a period of long dryness. MESOHALINE WATER REGIME — Fig. 4 shows the the diagramm scheme. Salt or brackish water from 30 to 17/1.000 salinity, sometimes until 10/1.000. Turbid waters with mud in suspension, chestnut, claveyous waters; shore dirty black mud without waving bursting; the waters are warmer and shorner than those of the polihaline regime. Mangrove shore with the mangrove trees : Rhizophora mangle L., Avicennia sp., Laguncularia sp., and the »cotton tree of sea» Hibiscus sp. Fauna: the great land crab «guaimú» Cardisoma guanhumi Latr., ashore in dry firm land. There is the real land crab Ucides cordatus (L.) in wetting mud and in neigh¬ bourhood of the burrows of the fiddler-crabs of genus Uca. On stones and in the roots of the Rhizophora inhabits the brightly colored mangrove-tree-crab («aratu» Portuguese nickname) Goniopsis cruentata (Latreille) and the sparingly the big oyster Ostrea rhizophorae Guild. Lower is the region of barnacles Balanus amphitrite var. communis Darwin and var. niveus Darwin; Balanus tintinnabulum var. tintinnabulum (L.) doesn't grow in this brackish water; lower is the region of Pelecipoda with prepollency of Venus and Cytherea shell-fishes and the Panopeus mud crab; there are the sea lettuce Ulva and the Gastreropod Cerithium. The Paguridae Clibanarius which lives in the empty shells of Gasteropod molluscs, and the sessile ascidians Tethium plicatum (Lesuer) appears in some seasons. In the bottom there is a black argillous mud where the «one landed shrimps» Alpheus sp. is hidden. OLIGOHALINE WATER REGIME — The salinity is lower than 10/1.000. average 8/1.000. There are no barnacles and no sea-beetles Isopods of genus Lygia; on the hay of the shore there are several graminea. This brackish water pervades by mouthes of rivers and penetrates until about 3 kilometers river above. While there is some salt dissolved in water, there are some mud crabs of the genus Uca, Sesarma, Metasesarma and Chasmagnatus. The presence of floating green plants coming from the rivers in the waters of a region indicated the oligohaline waters, with low salt content because when the average of NaCl increases above 8/1.000 these plants die and become rusty colored.

Anatomy and histology of Embolyntha batesi MacLahlan, 1877 (Embiidina)

The Embioptera are rather generalized insects whose internal anatomy is simple and not subject to great modifications. For this reason these insects form an ideal group for elementary anatomical and histological studies (fig. 2). The digestive tract is a long, simple tube without convolutions or diverticulae from the buccal cavity to the rectum. The buccal structures are of the chewing type. The oesophagus and ingluvia are differentiated only by slight dilation of their walls. In nymphs and females the proventriculus is very distinct due to folds which flatten as the structure becomes packed with food. The enteron is the largest in such forms and in both sexes limited caudally by the Malpighian tubules. The proctodeus has six large rectal papillae. The nervous system is complete with only the fifth abdominal segment lacking a ganglion in the metathorax includes the ganglion of the first abdominal segment. The brain exhibits very clear structure in histological sections. The tracheal system includes two pairs of thoracic spiracles and eight abdominal pairs. Only th metathoracic spiracle has an air expiration function; all others serve for inspiration. Various structures in the spiracles protect the atrium. The circulatory system includes a long, simple dorsal vessel which extends forward from the ninth abdominal segment into the cranium. It opens anteriorly near the circumoesophageal connectives. The dorsal vessel has a pair of ostia and valves corresponding to each abdominal and thoracic segment. It lacks the diverticulae or folds commonly found in more highly evolved insects. The excretory system is represented by Malphighian tubules, pericardial cells, and fat-body. The number and disposition of Malpighian tubules is variable within the order. The pericardial cells are localized around the entire dorsal vessel up to the opening of the aorta in the head. The fat-bodies form compact layers in the dorsal and ventral regions of the body. In males they are more developed in the abdominal region. The mandibles, maxillae, and salivary glands are of a simple type with very few cytological modifications. Only the salivary glands which extend into the mesothoracic region show appreciable specialization. The reproductive system is bi-sixual and shows considerable sexual dimorphism. Males have five pair of testes with a metameric disposition, two distinct ducts, two epidymis, and the ejaculatory organs. The accessory glands vary in number and size and open in the anterior portion of the ejaculatory duct. The female reproductive organs are of the panoistic type. The system includes five pairs of ovarioles, two long paired oviducts a small, unpaired oviduct and the spermatheca which opens in the vagina. Reproduction usually involves a union of male and female gametes, and eggs are usually laid in clusters attached to a substrate.

Factors influencing the development of Plasmodium gallinaceum in Aedes fluviatilis

Aedes fluviatilis is susceptible to infection by Plasmodium gallinaceum and is a convenient insect host for the malaria parasite in countries where Aedees aegypti cannot be maintained in laboratories. In South America, for instance, the rearing of A. aegypti the main vector of urban yellow fever, is not advaisable because of the potential health hazard it represents. Our results of the comparative studies carried out between the sporogonic cycle produced with two lines of P. gallinaceum parasites into A. fuviatilis were as follows. As proved for A. aegypti, mosquito infection rates were variable when A. fluviatilis blood-fed on chicks infected with and old syringe-passaged strain of P. gallinaceum. Oocysts developed in 41% of those mosquitos and the mean peak of oocyst production was 56 per stomach. Salivary gland infections developed in about 6% of the mosquitos. The course of sporogony was unrelated to the size of the inoculum administered to chicks or to the route by which the birds were infected. The development of infected salivary glands was unrelated to oocyst production. Sporogony of P. gallinaceum was more uniform when mosquitos blood-fed on chicks infected with a sporozoite-passaged strain. Oocysts developed in about 50% of those mosquitoes and the mean peak of oocyst production was 138 per stomach, with some individuals having as many as 600-800 oocysts. Infected salivary glands developed in a mean of 27% of the mosquitos but, in some batches, was a high as 50%. Patterns of salivary gland parasitism were similar to those of oocyst production. The course of sporogony of P. gallinaceum in A. fluviatilis is analized in relation to degree of parasitemia and gametocytemia in the vertebrate host.

Role of cytokines in secondary lymphoid organ development

Summary Secondary lymphoid organs are sites of antigen presentation, clonal expansion of B and lymphocytes, and affinity maturation of B lymphocytes. In the intestine, these immune functions occur mainly in Peyer's patches (PP). PP develop through the interplay of two main cell types, haematopoietic cells and meserichyrnal cells. One particular haematopoietic cell type was identified as the inductive cell type in the formation of both PP and lymph nodes and was therefore designated as lymphoid tissue inducer cell. For a successful PP organogenesis, the crucial molecular components involved in the crosstalk of inducer cells and their mesenchymal target cells are adhesion molecules, lymphotoxin (LT) family members, and cytokines. In particular, the interleukin 7 receptor (IL-7R) expressed on inducer cells is absolutely required. To investigate the contribution of the ligand for the IL-7R. the cytokine IL-7, in the process of PP formation, we analyzed double transgenic (TG) mice. These mice resulted from an interbreeding of an IL-7TG mouse strain where the transgene is under the control of the MHC class II promoter with a second transgenic mouse strain, which overexpresses a transactivator for MHC class II genes. Double TG offsprings revealed higher levels of IL-7 mRNA occuring earlier in embryogenesis. Consequently, double TG mice showed a striking phenotype with a 3- to 5-fold increase in PP numbers compared to single IL-7TG or control littermates. Analysis of embryonic double TG intestines demonstrated that the process of PP development was already elevated during development as early as the embryonic day 16.5. Importantly, inducer cells were significantly increased in numbers in these embryonic intestines. Furthermore, the expression of LT? mRNA, which at this early time point is exclusively expressed by inducer cells, was also increased in double TG animals. These data clearly indicate a direct influence of IL-7 on the expansion of lymphoid tissue inducer cells and on the availability of LT? leading to a higher frequency of developing PP in fetal life. Interestingly, in addition to an enhanced frequency of PP development, in double TG mice, three additional phenotypic differences were observed. i) Lymphocyte infiltration in various non-lymphoid organs, such as stomach, salivary gland, and liver. Subsequent analysis demonstrated that B lymphocytes were predominant within these tertiary lymphoid structures. ii) Ectopic lymph node-like structures containing both B and T lymphocytes were found near the inguinal lymph node. iii) Double TG mice had a severe bone resorption syndrome most likely as a consequence of the pro-osteoclastic effect of IL-7. Taken together, these results show that IL-7 plays a key role in the homeostasis of inducer cells, in the generation of PP in the gut, in the formation of ectopic lymphoid tissue, and in bone resorption. Résumé Les organes lymphoïdes secondaires sont les lieux de présentation des antigènes aux lymphocytes, permettant l'expansion des lymphocytes B et T et la maturation d'affinité des lymphocytes B. Dans l'intestin, ces fonctions immunitaires se déroulent dans les plaques de Peyer (PP). Ces plaques se développent grâce à l'interaction des cellules hématopoïétiques avec des cellules mésenchymales. Un type particulier de cellules hématopoïétiques a été identifié comme cellule inductrice dans la formation des PP et des ganglions lymphatiques et de ce fait a été désigné cellule inductrice des tissus lymphoïdes. Durant l'organogénèse des PP, les composants moléculaires cruciaux impliqués dans l'interaction des cellules inductrices et des cellules mésenchymales sont les molécules d'adhésion, les membres de la famille des lymphotoxines (LT) et les cytokines. En particulier, le récepteur de l'interleukine 7 (IL-7R) exprimé par les cellules inductrices est absolument nécessaire. Pour étudier le rôle du ligand de l'IL-7R, l'interleukine IL-7, dans la formation des PP, nous avons croisé une lignée de souris transgénique (TG) surexprimant IL-7 sous contrôle du promoteur MHC class Il avec une lignée de souris transgénique surexprimant un transactivateur des genes MHC class II. Les souris doubles TG présentent une concentration élevée d'ARNm de l'IL-7 durant l'embryogénèse, ce qui résulte en une augmentation du nombre de PP de 3 à 5 fois en comparaison aux souris ayant seul le transgène IL-7 et aux souris contrôles. L'analyse des intestins des souris doubles TG démontre que le processus de développement des PP était élevé dès le jour 16.5 du développement embryonnaire. L'augmentation du nombre des cellules inductrices dans ces intestins embryonnaires est signilicative. De plus l'expression de l'ARNm LT?, qui à ce stade précoce est exclusivement exprimé dans les cellules inductrices, est également augmenté dans les doubles TG. Ces résultats indiquent clairement une influence directe d'IL-7 sur l'expansion des cellules inductrices des tissues lymphoïdes et sur la synthèse de LT? induisant une augmentation des PP se développant durant la vie foetale. En plus du développement accru des PP dans les souris doubles TG, trois différences phénotypiques ont été observées. i) L'infiltration lymphocytaire dans différents organes non-lymphoïdes, comme l'estomac, les glandes salivaires et le foie. Des analyses complémentaires ont demontré que les lymphocytes B étaient prédominants dans ces structures lymphoïdes tertiaires. ii) Des structures de ganglions lymphatiques ectopiques contenant des lymphocytes B et T ont été trouvées près des ganglions lymphatiques inguinaux. iii) Les souris doubles TG présentent un syndrome de résorption osseuse sévère probablement dû à l'effet pro-osteoclaste d'IL-7. Globalement, ces résultats montrent que IL-7 joue un rôle clé dans l'homéostasie des cellules inductrices dans la génèse de PP de l'intestin, dans la formation des tissus lymphoïdes ectopiques et dans la résorption osseuse.

Vector salivation and parasite transmission

Saliva of blood-sucking arthropods contains substances that counteract the host's hemostatic and inflammatory reactions, allowing the arthropod to locate blood and keep it flowing during the blood meal. Parasites may manipulate this system in order to achieve increased transmission, both to vertebrate and to invertebrate hosts. Additionally, salivary pharmacological substances may locally immunosupress the delivery site, allowing initial colonization of the vertebrate host by the parasite.

Chirurgie

2007 was marked by a growing trend towards minimal invasive surgery and enhanced recovery, especially in visceral surgery. In comparison to the laparoscopic revolution in the eighties, Natural orifice transluminal endoscopic surgery (NOTES) must be watched on closely, and will probably have to be taken into account in a near future. Minimal invasive procedures in oesophageal cancer surgery have proved both efficient and oncologically safe. Implementation of Fast track protocols now permits a much faster patient's return to normal daily activity. In hepatobiliary and pancreatic surgery, multidisciplinary efforts have been done to better select patients, widen the indications and increase efficiency.

Genetic diversity and differentiation processes in the ploidy series of Olea europaea L.: a multiscale approach from subspecies to insular populations.

Geographical isolation and polyploidization are central concepts in plant evolution. The hierarchical organization of archipelagos in this study provides a framework for testing the evolutionary consequences for polyploid taxa and populations occurring in isolation. Using amplified fragment length polymorphism and simple sequence repeat markers, we determined the genetic diversity and differentiation patterns at three levels of geographical isolation in Olea europaea: mainland-archipelagos, islands within an archipelago, and populations within an island. At the subspecies scale, the hexaploid ssp. maroccana (southwest Morocco) exhibited higher genetic diversity than the insular counterparts. In contrast, the tetraploid ssp. cerasiformis (Madeira) displayed values similar to those obtained for the diploid ssp. guanchica (Canary Islands). Geographical isolation was associated with a high genetic differentiation at this scale. In the Canarian archipelago, the stepping-stone model of differentiation suggested in a previous study was partially supported. Within the western lineage, an east-to-west differentiation pattern was confirmed. Conversely, the easternmost populations were more related to the mainland ssp. europaea than to the western guanchica lineage. Genetic diversity across the Canarian archipelago was significantly correlated with the date of the last volcanic activity in the area/island where each population occurs. At the island scale, this pattern was not confirmed in older islands (Tenerife and Madeira), where populations were genetically homogeneous. In contrast, founder effects resulted in low genetic diversity and marked genetic differentiation among populations of the youngest island, La Palma.

A cronologia da descoberta dos transmissores da malária na Amazônia brasileira

In the Amazon Region of Brazil, during the first three decades of this century, anophelines of the subgenus Nyssorhynchus not precisely identified to species were regarded as the probable malaria vectors. In 1931 and 1933 Anopheles darlingi, and in 1942-1946 An. aquasalis were confirmed as carriers, the former in the interior, the latter along the coast, because of their habits and salivary gland infection. An. albitarsis and An. braziliensis seemed to be occasional, secondary vectors. Forty years later, through immunological tests, other species are being pointed as naturally infected: An. triannulatus, An. nuneztovari, An. oswaldoi, An. strodei, An. galvaoi and An. peryassui. The importance of all incriminated species except An. darlingi (the main vector wherever present) and An. aquasalis has yet to be measured.

Culex saltanensis Dyar, 1928: natural vector of Plasmodium juxtanucleare in Rio de Janeiro, Brazil

Searching for the natural vector of Plasmodium juxtanucleare in an enzootic locality: Granjas Calábria (33% of the chickens infected), Jacarepaguá, in Rio de Janeiro, Brazil, 13 comparative captures of mosquitoes were carried out, simultaneously on man (out-doors) and on chiken (in a poultry-yard), between 6 and 9 p.m., from September to March 1989. Culex saltanensis was the most frequent species in captures on chicken, accounting for 41.7% of the mosquitoes collected on this bait, showing to be highly ornithophilic (90% captured on chicken versus 10% on man). Seven specimens of Cx. saltanensis were found naturally infected in granjas Calábria: five with mature pedunculate oocysts and two with sporozoites (on in the haemocoele and one in the salivary glands). These sporozoites porudced an infection by P. juxtanucleare in a chick, which had parasitemia on day 41 after inoculation. One Cx. coronator was found with mature pedunculate oocysts. Culex saltanensis was regarded as primary vector of P. juxtanucleare in Rio de Janeiro for being highly ornithophilic and in enough density to maintain the transmission, having been found with infective sporozoites in its salivary glands, and being susceptible to the parasite and able to transmit experimentally it by the bite.

The distribution of agglutinins and lytic activity against Trypanosoma rangeli and erythrocytes in Rhodnius prolixus and Triatoma infestans tissue extracts and haemolymph

Haemolymph, heads, salivary glands, crops, midguts, hindguts, and Malpighian tubules from Rhodnius prolixus and Triatoma infestans were extracted in phosphate or Tris buffer saline with calcium, and tested for agglutination and lytic activities by microtitration against both vertebrateerythrocytes and cultured epimatigote forms of Trypanosoma rangeli. Haemagglutination activity against rabbit erythrocytes was found in the crop, midgut and hindgut extracts of T. infestans but only in the haemolymph of R. prolixus. Higher titres of parasite agglutinins were found in R. prolixus haemolymph than T. infestans, whilst the converse occurred for the tissue extracts. In addition, the extracts of T. infestans salivary glands, but not those of R. prolixus, showed a trypanolytic activity that was heat-inactivated and was not abolished by pre-incubation with any of the sugars or glycoproteins tested. T. infestans, which is refractory to infection by T. rangeli, thus appears to contain a much wider distribution of agglutinating and trypanolytic factors in its tissues than the more susceptible species, R. prolixus

Anàlisi socio-ambiental de les bordes de la Vall d'Estaon (Pallars Sobirà) i de la biodiversitat associada

Aquest projecte ha estat desenvolupat entre l’octubre de 2008 i el juliol de 2009 per un equip d’estudiants de Ciències Ambientals de la Universitat Autònoma de Barcelona. L’objecte d’estudi principal han estat les bordes, construccions agroramaderes utilitzades tradicionalment per a emmagatzemar l’herba i estabular-hi el bestiar. D’altra banda, pel que fa la biodiversitat, s’ha realitzat un estudi de la vegetació de pedra seca, i una primera aproximació a l’estudi dels rat-penats, espècies protegides que utilitzen les bordes com a refugi. L’àmbit d’estudi ha estat la Vall d'Estaon dins el municipi de Vall de Cardós, a la comarca del Pallars Sobirà, Catalunya. Tota la superfície d’estudi es troba dins de l’àmbit del Parc Natural de l’Alt Pirineu (PNAP) i, per tant, sota la seva protecció. Per a la realització d’aquest estudi, s’ha utilitzat la metodologia emprada en el projecte del Bosc de Virós (Mestres et al.,2007). S’elabora un inventari de bordes i un altre de biodiversitat a partir de les dades recopilades amb la observació al camp i es realitzen entrevistes als gestors de la zona, antics i nous propietaris. En l’anàlisi dels resultats, s’observa que les bordes han perdut la seva funcionalitat tradicional i moltes d’elles s’han abandonat. Aquests fets provoquen la degradació d’aquestes construccions i la conseqüent pèrdua de patrimoni. D’altra banda la idea de recuperar les activitats tradicionals esdevé poc realista i es combina amb la impossibilitat d’aplicar nous usos per la protecció que exerceix la figura de Parc Natural. Així doncs, les bordes es troben enmig d’una situació estàtica i paradoxal entre la voluntat i desig de conservació i l'imminent i accelerat procés d’abandonament i degradació.