969 resultados para 6015 PLANETARY SCIENCES: COMETS AND SMALL BODIES Dust


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BACKGROUND: With many atypical antipsychotics now available in the market, it has become a common clinical practice to switch between atypical agents as a means of achieving the best clinical outcomes. This study aimed to examine the impact of switching from olanzapine to risperidone and vice versa on clinical status and tolerability outcomes in outpatients with schizophrenia in a naturalistic setting. METHODS: W-SOHO was a 3-year observational study that involved over 17,000 outpatients with schizophrenia from 37 countries worldwide. The present post hoc study focused on the subgroup of patients who started taking olanzapine at baseline and subsequently made the first switch to risperidone (n=162) and vice versa (n=136). Clinical status was assessed at the visit when the first switch was made (i.e. before switching) and after switching. Logistic regression models examined the impact of medication switch on tolerability outcomes, and linear regression models assessed the association between medication switch and change in the Clinical Global Impression-Schizophrenia (CGI-SCH) overall score or change in weight. In addition, Kaplan-Meier survival curves and Cox-proportional hazards models were used to analyze the time to medication switch as well as time to relapse (symptom worsening as assessed by the CGI-SCH scale or hospitalization). RESULTS: 48% and 39% of patients switching to olanzapine and risperidone, respectively, remained on the medication without further switches (p=0.019). Patients switching to olanzapine were significantly less likely to experience relapse (hazard ratio: 3.43, 95% CI: 1.43, 8.26), extrapyramidal symptoms (odds ratio [OR]: 4.02, 95% CI: 1.49, 10.89) and amenorrhea/galactorrhea (OR: 8.99, 95% CI: 2.30, 35.13). No significant difference in weight change was, however, found between the two groups. While the CGI-SCH overall score improved in both groups after switching, there was a significantly greater change in those who switched to olanzapine (difference of 0.29 points, p=0.013). CONCLUSION: Our study showed that patients who switched from risperidone to olanzapine were likely to experience a more favorable treatment course than those who switched from olanzapine to risperidone. Given the nature of observational study design and small sample size, additional studies are warranted.

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This thesis is devoted to investigations of three typical representatives of the II-V diluted magnetic semiconductors, Zn1-xMnxAs2, (Zn1-xMnx)3As2 and p-CdSb:Ni. When this work started the family of the II-V semiconductors was presented by only the compounds belonging to the subgroup II3-V2, as (Zn1-xMnx)3As2, whereas the rest of the materials mentioned above were not investigated at all. Pronounced low-field magnetic irreversibility, accompanied with a ferromagnetic transition, are observed in Zn1-xMnxAs2 and (Zn1-xMnx)3As2 near 300 K. These features give evidence for presence of MnAs nanosize magnetic clusters, responsible for frustrated ground magnetic state. In addition, (Zn1-xMnx)3As2 demonstrates large paramagnetic response due to considerable amount of single Mn ions and small antiferromagnetic clusters. Similar paramagnetic system existing in Zn1-xMnxAs2 is much weaker. Distinct low-field magnetic irreversibility, accompanied with a rapid saturation of the magnetization with increasing magnetic field, is observed near the room temperature in p- CdSb:Ni, as well. Such behavior is connected to the frustrated magnetic state, determined by Ni-rich magnetic Ni1-xSbx nanoclusters. Their large non-sphericity and preferable orientations are responsible for strong anisotropy of the coercivity and saturation magnetization of p- CdSb:Ni. Parameters of the Ni1-xSbx nanoclusters are estimated. Low-temperature resistivity of p-CdSb:Ni is governed by a hopping mechanism of charge transfer. The variable-range hopping conductivity, observed in zero magnetic field, demonstrates a tendency of transformation into the nearest-neighbor hopping conductivity in non-zero magnetic filed. The Hall effect in p-CdSb:Ni exhibits presence of a positive normal and a negative anomalous contributions to the Hall resistivity. The normal Hall coefficient is governed mainly by holes activated into the valence band, whereas the anomalous Hall effect, attributable to the Ni1-xSbx nanoclusters with ferromagnetically ordered internal spins, exhibits a low-temperature power-law resistivity scaling.

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The technological advances and new organisation of the economy together with a change in ideas in consumer habits andlifestyle that have happened in the last 25 years have placed us in a new state of capitalism. The spatial translation of thisnew state has been immediate and implies among other changes the overcoming of the concept of scale. Commercialspaces and those of leisure and tourism offer us an unbeatable opportunity of exemplifying these changes because they arethe most effected by the new postmodern tendencies

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The thesis discusses the regulation of foodstuffs and medicines, and particularly the regulation of functional foods. Legal systems investigated are the EU and China. Both are members of the WTO and Codex Alimentarius, which binds European and Chinese rules together. The study uses three Chinese berries as case examples of how product development faces regulation in practice. The berries have traditional uses as herbal medicines. Europe and China have similar nutrition problems to be resolved, such as obesity, cardiovascular disease, and diabetes. The three berries might be suitable raw materials for functional foods. Consumer products with health-enhancing functions, such as lowering blood pressure, might legally be classifi ed either as foodstuffs or medicines. The classifi cation will depend on functions and presentation of the product. In our opinion, food and medicine regulation should come closer together so the classifi cation issue would no longer be an issue. Safety of both foodstuffs and medicines is strictly regulated. With medicines, safety is a more relative concept, where benefi ts of the product are compared to side-effects in thorough scientifi c tests and trials. Foods, on the other hand, are not allowed to have side-effects. Hygiene rules and rules on the use of chemicals apply. In China, food safety is currently at focus as China has had several severe food scandals. Newly developed foods are called novel foods, and are specifi cally regulated. The current European novel food regulation from 1997 treats traditional third country products as novel. The Chinese regulation of 2007 also defi nes novel foods as something unfamiliar to a Chinese consumer. The concepts of novel food thus serve a protectionist purpose. As regards marketing, foods are allowed to bear health claims, whereas medicines bear medicinal claims. The separation is legally strict: foods are not to be presented as having medicinal functions. European nutrition and health claim regulation exists since 2006. China also has its regulation on health foods, listing the permitted claims and how to substantiate them. Health claims are allowed only on health foods. The European rules on medicines include separate categories for herbal medicines, traditional herbal medicines, and homeopathic medicines, where there are differing requirements for scientifi c substantiation. The scientifi c and political grounds for the separate categories provoke criticism. At surface, the Chinese legal system seems similar to the European one. To facilitate trade, China has enacted modern laws. Laws are needed as the country moves from planned economy to market economy: ‘rule of law’ needs to replace ‘rule of man’. Instead of being citizens, Chinese people long were subordinates to the Emperor. Confucius himself advised to avoid confl ict. Still, Chinese people do not and cannot always trust the legal system, as laws are enforced in an inconsistent manner, and courts are weak. In China, there have been problems with confl icting national and local laws. In Europe, the competence of the EU vs. the competence of the Member States is still not resolved, even though the European Commission often states that free trade requires harmonisation. Food and medicine regulation is created by international organisations, food and medicine control agencies, standards agencies, companies and their organisations. Regulation can be divided in ‘hard law’ and ‘soft law’. One might claim that hard law is in crisis, as soft law is gaining importance. If law is out of fashion, regulation certainly isn’t. In the future, ‘law’ might mean a process where rules and incentives are created by states, NGOs, companies, consumers, and other stakeholders. ‘Law’ might thus refer to a constant negotiation between public and private actors. Legal principles such as transparency, equal treatment, and the right to be heard would still be important.

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The year 2013 marks the centennial of that wondrous year in which Niels Bohr proposed a novel theory about the constitution of atoms and small molecules after which the way we regard atoms and their behaviour began to be drastically altered. Bohr drew on several sources for his original description of the atoms, most importantly on spectroscopy and Balmer's equation thereof, the new quantum hypothesis advanced a few years earlier by Planck, and the planetary atom proposed by Rutherford. Although Bohr's ideas were to be eventually overtaken by the advent of quantum mechanics, his theory was the basis of a new thinking about atoms and molecules which constitutes an invaluable asset in the development of science ever since.

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Många förbränningsanläggningar som bränner utmanande bränslen såsom restfraktioner och avfall råkar ut för problem med ökad korrosion på överhettare och/eller vattenväggar pga. komponenter i bränslena som är korrosiva. För att minimera problemen i avfallseldade pannor hålls ångparametrarna på en relativt låg nivå, vilket drastiskt minskar energiproduktionen. Beläggningarna i avfallseldade pannor består till största delen av element som är förknippade med högtemperaturkorrosion: Cl, S, alkalimetaller, främst K och Na, och tungmetaller som Pb och Zn, och det finns också indikationer av Br-förekomst. Det låga ångtrycket i avfallseldade pannor påverkar också stålrörens temperatur i pannväggarna i eldstaden. I dagens läge hålls temperaturen normalt vid 300-400 °C. Alkalikloridorsakad (KCl, NaCl) högtemperaturkorrosion har inte rapporterats vara relevant vid såpass låga temperaturer, men närvaro av Zn- och Pb-komponenter i beläggningarna har påvisats förorsaka ökad korrosion redan vid 300-400 °C. Vid förbränning kan Zn och Pb reagera med S och Cl och bilda klorider och sulfater i rökgaserna. Dessa tungmetallföreningar är speciellt problematiska pga. de bildar lågsmältande saltblandningar. Dessa lågsmältande gasformiga eller fasta föreningar följer rökgasen och kan sedan fastna eller kondensera på kallare ytor på pannväggar eller överhettare för att sedan bilda aggressiva beläggningar. Tungmetallrika (Pb, Zn) klorider och sulfater ökar risken för korrosion, och effekten förstärks ytterligare vid närvaro av smälta. Motivet med den här studien var att få en bättre insikt i högtemperaturkorrosion förorsakad av Zn och Pb, samt att undersöka och prediktera beteendet och motståndskraften hos några stålkvaliteter som används i överhettare och pannväggar i tungmetallrika förhållanden och höga materialtemperaturer. Omfattande laboratorie-, småskale- och fullskaletest utfördes. Resultaten kan direkt utnyttjas i praktiska applikationer, t.ex. vid materialval, eller vid utveckling av korrosionsmotverkande verktyg för att hitta initierande faktorer och förstå deras effekt på högtemperaturkorrosion.

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Cells of epithelial origin, e.g. from breast and prostate cancers, effectively differentiate into complex multicellular structures when cultured in three-dimensions (3D) instead of conventional two-dimensional (2D) adherent surfaces. The spectrum of different organotypic morphologies is highly dependent on the culture environment that can be either non-adherent or scaffold-based. When embedded in physiological extracellular matrices (ECMs), such as laminin-rich basement membrane extracts, normal epithelial cells differentiate into acinar spheroids reminiscent of glandular ductal structures. Transformed cancer cells, in contrast, typically fail to undergo acinar morphogenic patterns, forming poorly differentiated or invasive multicellular structures. The 3D cancer spheroids are widely accepted to better recapitulate various tumorigenic processes and drug responses. So far, however, 3D models have been employed predominantly in the Academia, whereas the pharmaceutical industry has yet to adopt a more widely and routine use. This is mainly due to poor characterisation of cell models, lack of standardised workflows and high throughput cell culture platforms, and the availability of proper readout and quantification tools. In this thesis, a complete workflow has been established entailing well-characterised 3D cell culture models for prostate cancer, a standardised 3D cell culture routine based on high-throughput-ready platform, automated image acquisition with concomitant morphometric image analysis, and data visualisation, in order to enable large-scale high-content screens. Our integrated suite of software and statistical analysis tools were optimised and validated using a comprehensive panel of prostate cancer cell lines and 3D models. The tools quantify multiple key cancer-relevant morphological features, ranging from cancer cell invasion through multicellular differentiation to growth, and detect dynamic changes both in morphology and function, such as cell death and apoptosis, in response to experimental perturbations including RNA interference and small molecule inhibitors. Our panel of cell lines included many non-transformed and most currently available classic prostate cancer cell lines, which were characterised for their morphogenetic properties in 3D laminin-rich ECM. The phenotypes and gene expression profiles were evaluated concerning their relevance for pre-clinical drug discovery, disease modelling and basic research. In addition, a spontaneous model for invasive transformation was discovered, displaying a highdegree of epithelial plasticity. This plasticity is mediated by an abundant bioactive serum lipid, lysophosphatidic acid (LPA), and its receptor LPAR1. The invasive transformation was caused by abrupt cytoskeletal rearrangement through impaired G protein alpha 12/13 and RhoA/ROCK, and mediated by upregulated adenylyl cyclase/cyclic AMP (cAMP)/protein kinase A, and Rac/ PAK pathways. The spontaneous invasion model tangibly exemplifies the biological relevance of organotypic cell culture models. Overall, this thesis work underlines the power of novel morphometric screening tools in drug discovery.

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The modern business development of China began during 1978 and during the last decades Chinese have created one of the most dynamic and strongest economies in the world. China is now second largest trading power calculated in dollars. The special characteristic of this economic development is that it is not copy of any existing economy, instead the developments have been strongly influenced by the Chinese cultural characteristics. One cultural characteristic, guanxi, which is a “network of services and counter- services” is argued to be major component of successful business in China where these changes of services happen between people but also between companies. Obtaining introductions and the guanxi when doing business in China will give attentive audience and security for companies business. Despite the evidenced importance of guanxi, China´s business environment is rapidly changing towards Western economies, which might then reduce the importance of guanxi. Therefore the current impact of guanxi is a important topic to study. The main purpose of this study is to explore the impact of guanxi for Western big and small sized multinational companies´ business processes when doing business in China. This study looks What is the impact of guanxi in contemporary Chinese business environment for foreign companies doing business in China. Sub-questions in this research focus on what is the impact of guanxi on corporate reputation, management and negotiations. Findings present a mixed view where the importance of guanxi is not anymore critical, especially among younger people in the cities, however guanxi was clearly important outside the cities and when dealing with government officials. Efficient use of guanxi can be extremely profitable especially during early stages of business operations and guanxi plays role when bargaining prices and ensuring product quality from the factories. Therefore guanxi should be considered as essential element for successful business in China.

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This thesis presents an approach for formulating and validating a space averaged drag model for coarse mesh simulations of gas-solid flows in fluidized beds using the two-fluid model. Proper modeling for fluid dynamics is central in understanding any industrial multiphase flow. The gas-solid flows in fluidized beds are heterogeneous and usually simulated with the Eulerian description of phases. Such a description requires the usage of fine meshes and small time steps for the proper prediction of its hydrodynamics. Such constraint on the mesh and time step size results in a large number of control volumes and long computational times which are unaffordable for simulations of large scale fluidized beds. If proper closure models are not included, coarse mesh simulations for fluidized beds do not give reasonable results. The coarse mesh simulation fails to resolve the mesoscale structures and results in uniform solids concentration profiles. For a circulating fluidized bed riser, such predicted profiles result in a higher drag force between the gas and solid phase and also overestimated solids mass flux at the outlet. Thus, there is a need to formulate the closure correlations which can accurately predict the hydrodynamics using coarse meshes. This thesis uses the space averaging modeling approach in the formulation of closure models for coarse mesh simulations of the gas-solid flow in fluidized beds using Geldart group B particles. In the analysis of formulating the closure correlation for space averaged drag model, the main parameters for the modeling were found to be the averaging size, solid volume fraction, and distance from the wall. The closure model for the gas-solid drag force was formulated and validated for coarse mesh simulations of the riser, which showed the verification of this modeling approach. Coarse mesh simulations using the corrected drag model resulted in lowered values of solids mass flux. Such an approach is a promising tool in the formulation of appropriate closure models which can be used in coarse mesh simulations of large scale fluidized beds.

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Degenerative myxomatous mitral valve (DMMV) is a heart disease of high incidence in small animal clinical medicine, affecting mainly older dogs and small breeds. Thus, a scientific investigation was performed in order to evaluate the clinical use of the medicines furosemide and enalapril maleate in dogs with this disease in CHF functional class Ib before and after the treatment was established. For this purpose 16 dogs with the given valve disease were used, separated into two groups: the first received furosemide (n=8) and the second received enalapril maleate (n=8) throughout 56 days. The dogs were evaluated in four stages (T0, T14, T28 and T56 day) in relation to clinical signs, hematological, biochemical and serum assessment, which included serum angiotensin converting enzyme (ACE) and aldosterone, as well as radiography, electrocardiography, Doppler-echocardiography and blood pressure. The results regarding the clinical, hematological and serum chemistry evaluations revealed no significant changes in both groups, but significant reductions in the values of ACE and aldosterone in the group receiving enalapril maleate were verified. The radiographic examination revealed reductions of VHS values and variable Pms wave of the electrocardiogram in both groups, but no changes in blood pressure values were identified. The echocardiogram showed a significant decrease of the variables LVDd/s in the studied groups and the FS% in animals that received only enalapril. Therefore, analysis of results showed that monotherapy based on enalapril maleate showed better efficiency of symptoms control in patients with CHF functional class Ib.

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A retrospective study of 24 cases of papillomas in dogs was performed from January 2001 to March 2011. Additionally, immunohistochemistry (IHC) was used to characterize and evaluate the samples. We found that disease was observed more in mixed breed dogs, ages ranging from 6 months to 10 years (mean 3.1 years), and there was no gender predilection. The main lesion sites were the skin (75%), lips (16.7%), and eyelids (8.3%). Upon histological evaluation, we observed papillary exophytic proliferation of squamous epithelium and papillary endophytic proliferation (inverted) in 87.5% and 12.5% of cases, respectively. The tumors were characterized by spinous layer hyperplasia (87.5%) with koilocytes (70.8%) and intranuclear pale basophilic inclusions bodies (8.3%), prominent granular layer with large amounts of keratohyalin granules (95.8%), and hyperkeratosis in the stratum corneum (100%). Positive immunostaining for Papillomavirus was found in 83.3% of cases, which were distributed between the granular layer and the stratum corneum. These findings indicate the following: that papillomas in dogs are caused by Papillomavirus, the viral cytopathic effect induces epithelial lesions, viral particles are found inside the cell nuclei, and inclusions bodies are rare.

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Tässä tutkimuksessa selvitetään ilman hitsauslisäainetta tapahtuvan laser–TIG–hybridihitsausprosessin soveltuvuus 6 mm ja 8 mm paksujen päittäisliitettyjen S355 K2 ja Laser 355 MC rakenneterästen hitsaukseen. Hitsien tarkastelussa huomio kiinnitetään hitsausnopeuteen, hitsien tunkeumaan, liittämistehokkuuteen, hitsien kovuuteen ja hitsausliitoksen ulkonäköön. Muita tutkittavia asioita ovat laser-TIG-hybridihitsattujen levyjen muodonmuutokset ja suuresta hitsausnopeudesta sekä pienestä t8/5 jäähtymisajasta johtuvat mahdolliset kylmähalkeamat. Laser-TIG-hybridihitsejä verrataan robotti-MAG- ja käsin MAG-hitseihin sekä kaarihitsausstandardin SFS-EN ISO 5817 hitsiluokkien mukaisiin raja-arvoihin. Laser-TIG-hybridihitsausprosessissa TIG-valokaari mahdollistaa tasaisen ja lähes roiskeettoman hitsin ja lasersäde aikaansaa syvän tunkeuman sekä tasalaatuisen juurihitsin. Laser-TIG-hybridihitsausprosessilla 6 mm paksut S355 K2 rakenneteräslevyt on mahdollista hitsata levyn yhdeltä puolelta kerralla valmiiksi. Paksummat 8 mm levyt voidaan hitsata levyn yhdeltä tai molemmilta puolilta suoritettavalla laser-TIG-hybridihitsauksella. Laser-TIG-hybridihitsausprosessilla hitsatut hitsit ovat hyvin siistejä ja lähes roiskeettomia. Verrattaessa laser-TIG-hybridihitsausprosessia muihin hitsausprosesseihin sen voidaan todeta olevan erittäin kilpailukykyinen 6 mm paksujen päittäisliitettyjen rakenneterästen hitsaamisessa, mutta se soveltuu myös 8 mm paksujen rakenneterästen hitsaamiseen. Tutkitut hitsit täyttävät kaarihitsausstandardin SFS-EN ISO 5817 B- ja D-hitsiluokkien mukaiset raja-arvot. Vertailukokeet 6 mm paksulla S355 rakenneteräksellä osoittavat, että yhdeltä puolelta suoritettavan laser-TIG-hybridihitsauksen hitsausnopeus on robotti-MAG-hitsaukseen verrattuna yli nelinkertainen ja MAG-käsinhitsaukseen verrattuna yli viisinkertainen. Laser-TIG-hybridihitsauksessa liittämistehokkuus on noin viisinkertainen robotti-MAGhitsaukseen verrattuna. Molemmilta puolilta suoritettavalla laser-TIG-hybridihitsauksella voidaan 8 mm paksulla S355 rakenneteräksellä saavuttaa noin kolminkertainen hitsausnopeus ja liittämistehokkuus robotti-MAG-hitsaukseen verrattuna. Laser-TIG-hybridihitsauksessa TIG-kaaren tuoman lisälämmön ansiosta suurillakin hitsausnopeuksilla (1 m/min) voidaan saavuttaa edulliset kovuusarvot. Kovuusmittausten tulosten perusteella 6 mm ja 8 mm paksujen S355 K2 ja Laser 355 MC rakenneterästen hitsit eivät ylittäneet kaarihitsausstandardin määrittelemää 350 HV kovuuden enimmäisrajaa. Laser-TIG-hybridihitsauksen edullisesta lämmöntuonnista johtuen levyjen pituus- ja poikittaissuuntaiset muodonmuutokset ovat noin 80 prosenttia pienemmät kuin käsin suoritettavassa MAG-hitsauksessa. Laser-TIG-hybridihitsausprosessilla käytetään I-railoa, mutta robotti-MAG- ja käsin MAG-hitsausprosesseilla joudutaan käyttämään V-railoa, jolloin lämmöntuonti ja siitä johtuvat muodonmuutokset ovat suuremmat. Korkea liittämistehokkuus ja edullinen lämmöntuonti merkitsevät vähäisempiä muodonmuutoksia ja siten merkittäviä säästöjä työ-, materiaali- ja energiakustannuksissa. 8 mm ja sitä paksummilla S355 rakenneteräksillä levyn yhdeltä puolelta suoritettava päittäisliitoksen hitsaaminen on laser-TIG hybridihitsauksella haastavaa, koska yli 200 A:n TIG-kaarivirralla suuri metallisula aiheuttaa avaimenreiän sulkeutumisen ja avaimenreiän alaosaan muodostuu kaasukuplia. Tästä voidaan tehdä sellainen johtopäätös, että päittäisliitettävien levyjen ilmarakoa pitäisi kasvattaa niin suureksi, että avaimenreiän sulavirtaus ei pääse estymään. Yli 0,25 mm:n ilmarako edellyttää lasersäteen vaaputusta tai säteen halkaisijan kasvattamista. Ilmaraon kasvattaminen edellyttää myös lisäaineen käyttöä. Tutkimustulosten perusteella laser-TIG-hybridihitsausprosessilla voidaan saavuttaa merkittäviä etuja ja kustannussäästöjä, joten sen hyödyntämistä kannattaa harkita 8 mm ja sitä ohuempien päittäisliitettävien tuotteiden konepaja- ja tehdastuotannossa. Laser-TIGhybridihitsausprosessi soveltuu esimerkiksi seuraavien tuotteiden hitsaamiseen: päittäisliitettävät levyt, palkit, koneenosat, putket, säiliöt ja erilaiset pyörähdyskappaleet.

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Abstract:Trematodes belonging to the family Eucotylidae, including Tanaisia(Paratanaisia)bragaiSantos, 1934are parasites of the kidney and ureter that affect several species of domestic and wild birds. Tanaisia bragaiis considered a low pathogenic parasite, but high worm burdens may determine clinical complications, including signs of apathy, weight loss, diarrhea and death. This paper describes the first report of infection by T. bragai in peacocks (Pavo cristatus), which constitutes a new host record and offers data on the lesions associated to this parasitism, although the degree of pathogenicity and parasite load may be considered mild. These birds did not exhibit clinical signs of parasitism. The macroscopic exam revealed discreet yellow spots on the liver. In the histological sections of the kidney, specimens of T. bragai were found in the collecting ducts, which were markedly dilated, with a thickened wall. Other findings included a mild inflammatory reaction in the wall of the ducts (but sometimes absent), flattening of lining epithelial cells and small, multifocal points of calcification around the collecting ducts. The microscopic examination of the parasites revealed trematodes with an elongated body, well-developed sub terminal oral sucker, pharynx present, short esophagus, cecum somewhat undulating or not, with blind end, testes symmetrical, equatorial, irregular in shape or slightly lobed, vitelline fields extending in both pre-ovarian and post ovarian fields, uterus very long, intercecal or sometimes overlapping the cecum and containing large quantities of eggs. The present findings suggest the need for further diagnostic studies on the prevalence of this trematode in peacocks as well as pathologic studies for the determination of the potential pathogenicity of this parasite in this species of bird. Moreover, infected peacocks could serve as carriers of T. bragai to be transferred to other bird species, thereby contributing to the dispersion of the parasite.

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Abstract: Mammary gland tumors are the most common type of tumors in bitches but research on survival time after diagnosis is scarce. The purpose of this study was to investigate the relationship between survival time after mastectomy and a number of clinical and morphological variables. Data was collected retrospectively on bitches with mammary tumors seen at the Small Animal Surgery Clinic Service at the University of Brasília. All subjects had undergone mastectomy. Survival analysis was conducted using Cox's proportional hazard method. Of the 139 subjects analyzed, 68 died and 71 survived until the end of the study (64 months). Mean age was 11.76 years (SD=2.71), 53.84% were small dogs. 76.92% of the tumors were malignant, and 65.73% had both thoracic and inguinal glands affected. Survival time in months was associated with age (hazard rate ratios [HRR] =1.23, p-value =1.4x10-4), animal size (HRR between giant and small animals =2.61, p-value =0.02), nodule size (HRR =1.09, p-value =0.03), histological type (HRR between solid carcinoma and carcinoma in a mixed tumor =2.40, p-value =0.02), time between diagnosis and surgery (TDS, with HRR =1.21, p-value =2.7x10-15), and the interaction TDS*follow-up time (HRR =0.98, p-value =1.6x10-11). The present study is one of the few on the subject matter. Several important covariates were evaluated and age, animal size, nodule size, histological type, TDS and TDS*follow up time were identified as significantly associated to survival time.

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A. peregrina var. falcata form mutualistic symbiosis with arbuscular mycorrhizal fungus. An anatomical and ultrastructural study was carried out to analyze some aspects of this simbiotic association as well as some root features. The results evidenced the presence of fibers with non-lignified thicked secondary walls in the stele and sparse papillae on root surface. A. peregrina var. falcata mycorrhizas presented features of Arum-type (intercellular hyphae) and Paris-type (extensive coils) arbuscular mycorrhiza. Their general appearance with extraradical hyphae, intracellular coils, intercellular hyphae and arbuscules, is in agreement with arbuscular mycorrhizas of several plants. The ultrastructural observations showed that in intercellular hyphae and arbuscules vacuoles were dominant and that in rough endoplasmatic reticulum and small vesicles seems to be associated with arbuscule senescence process.