Both cetaceans in the Brazilian Amazon show sustained, profound population declines over two decades

<div><p>Obligate river dolphins occur only in the rivers of Asia and South America, where they are increasingly subject to damaging pressures such as habitat degradation, food competition and entanglement in fishing gear as human populations expand. The Amazon basin hosts two, very different, dolphins—the boto or Amazon river dolphin (<i>Inia geoffrensis</i>) and the smaller tucuxi (<i>Sotalia fluviatilis</i>). Both species have wide geographical ranges and were once considered to be relatively abundant. Their IUCN Red List conservation status of Data Deficient (DD), due to limited information on threats, ecology, population numbers and trends, did not initially cause alarm. However, the development of dolphin hunting to provide fish bait at around the beginning of this millennium broadly coincided with the onset of a widespread perception that numbers of both species were in decline. Consequently, the need for population trend data to inform conservation advice and measures became urgent. This paper presents a 22-year time series of standardised surveys for both dolphins within the Mamirauá Reserve, Amazonas State, Brazil. Analysis of these data show that both species are in steep decline, with their populations halving every 10 years (botos) and 9 years (tucuxis) at current rates. These results are consistent with published, independent information on survival rates of botos in this area, which demonstrated a substantial drop in annual survival, commencing at around the year 2000. Mamirauá is a protected area, and is subject to fewer environmental pressures than elsewhere in the region, so there is no reason to suspect that the decline in dolphins within the Reserve is more pronounced than outside it. If South America's freshwater cetaceans are to avoid following their Asian counterparts on the path to a perilous conservation status, effective conservation measures are required immediately. Enforcement of existing fishery laws would greatly assist in achieving this.</p></div

Placentation in dolphins from the Amazon River Basin: the Boto, Inia geoffrensis, and the Tucuxi, Sotalia fluviatilis

A recent reassessment of the phylogenetic affinities of cetaceans makes it timely to compare their placentation with that of the artiodactyls. We studied the placentae of two sympatric species of dolphin from the Amazon River Basin, representing two distinct families. The umbilical cord branched to supply a bilobed allantoic sac. Small blood vessels and smooth muscle bundles were found within the stroma of the cord. Foci of squamous metaplasia occurred in the allanto-amnion and allantochorion. The interhemal membrane of the placenta was of the epitheliochorial type. Two different types of trophoblastic epithelium were seen. Most was of the simple columnar type and indented by fetal capillaries. However, there were also areolar regions with tall columnar trophoblast and these were more sparsely supplied with capillaries. The endometrium was well vascularised and richly supplied with actively secreting glands. These findings are consistent with the current view that Cetacea are nested within Artiodactyla as sister group to the hippopotamids

Radiative Corrections to the Aharonov-Bohm Scattering

We consider the scattering of relativistic electrons from a thin magnetic flux tube and perturbatively calculate the order $\alpha$, radiative correction, to the first order Born approximation. We show also that the second order Born amplitude vanishes, and obtain a finite inclusive cross section for the one-body scattering which incorporates soft photon bremsstrahlung effects. Moreover, we determine the radiatively corrected Aharonov-Bohm potential and, in particular, verify that an induced magnetic field is generated outside of the flux tube.Comment: 14 pages, revtex, 3 figure

Cylindrically symmetric inhomogeneous dust collapse with a zero expansion component

We investigate a class of cylindrically symmetric inhomogeneous Λ-dust spacetimes which have a regular axis and some zero expansion component. For Λ \neq 0, we obtain new exact solutions to the Einstein equations and show that they are unique, within that class. For Λ = 0, we recover the Senovilla– Vera metric and show that it can be locally matched to an Einstein–Rosen type of exterior. Finally, we explore some consequences of the matching, such as trapped surface formation and gravitational radiation in the exterior.We thank Jose Senovilla for suggesting solutions of the form (8) and (9) and for other very useful comments which led to substancial improvements in the paper. IB and FM are supported by Portuguese Funds through Fundacao para a Cincia e Tecnologia (FCT), within the Projects UID/MAT/00013/2013 and PTDC/MAT-ANA/1275/2014. FM and NOS acknowledge a grant received from UERJ and thank the warm hospitality from Instituto de Fisica, UERJ, Rio de Janeiro, where a great part of this work was completed. MFAdaSilva acknowledges the financial support from FAPERJ (no. E-26/171.754/2000, E-26/171.533.2002, E-26/170.951/2006, E-26/110.432/2009 and E-26/111.714/2010), Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) Brazil (no. 450572/2009-9, 301973/2009-1 and 477268/2010-2) and Financiadora de Estudos e Projetos (FINEP) Brazil.info:eu-repo/semantics/publishedVersio

Morphology, morphometry and ultrastructure of the Amazonian manatee (Sirenia: Trichechidae) spermatozoa

This study describes the morphological, morphometric and ultrastructural characteristics of the Amazonian manatee Trichechus inunguis (Natterer, 1883) spermatozoon. The spermatozoa were obtained from a urine sample of an adult T. inunguis kept in captivity. The spermatozoa were analyzed by light and transmission electron microscopy. The head of Amazonian manatee spermatozoa had a flat oval shape and a well distinguishable midpiece. The mean dimensions of the spermatozoa were: head length, 7.49 ± 0.24 µm; head width, 3.53 ± 0.19 µm; head thickness, 1.61 ± 0.13 µm; midpiece length, 11.36 ± 0.34 µm; flagellum length, 40.91 ± 1.94 µm; total tail length, 52.16 ± 1.06 µm; total spermatozoon length, 60.08 ± 1.40 µm. The Amazonian manatee spermatozoa were similar in shape to other sirenian spermatozoa; however, presenting a different size. This study describes, for the first time, the morphometric and ultrastructural characteristics of the Amazonian manatee spermatozoa, and also demonstrates the possible use of spermatozoa retrieved from urine samples for biological studies

Acquired tetanus: clinical and epidemiological characteristics of patients in an university hospital

INTRODUCTION: Notwithstanding its substantial decline over the last two decades, acquired tetanus is still a serious health problem in most developing countries. Epidemiological transition is often cited as an explanation for this decline, the increase in vaccination coverage of children being the most obvious cause. Few studies have looked carefully at the current epidemiological patterns of acquired tetanus in developing countries. METHODOLOGY: A descriptive, retrospective (series of cases). An acute care 400 - bed university referral hospital situated in a densely populated and highly urbanized area in Southeastern Brazil (Campinas, SP). Patient records the data-base analysed were from the Epidemiological Surveillance Unit of the hospital. RESULTS: In the 57 month period from January 1989 to March 1996 fifty-three patients were admitted with a diagnosis of acquired tetanus. Fifty patients had clinical confirmation, 3 were otherwise diagnosed. Thirty-two (64%) were male and 18 (36%) female. Fourteen (28%) were from rural areas and 36 (72%) from urban. Mean age was 47.6 years, with a median of 49.5. Of the rural patients, 42.85% were under 30 years and 21.42% were over 50, mean age was 36.21 with a median of 34.5. Fewer urban patients were under 30 (13.88%) than over 50 (58.33%), mean age was 52.19 with a median of 54.5. Trismus was the most frequent (92.0%) clinical sign on admittance, followed by abdominal muscular rigidity (84.0%). Treatment measures were uniform and included tetanus immune globulin, antibiotics, surgical debridement of the wound when feasible, diazepan or curare depending on the intensity of spasms. In the second half of the study period, penicillin was replaced by metronidazol. Overall case fatality rate was 20%, in patients that had to receive curare, it was 60%. Hospitalization exceeded 21 days in 56% (28) of the cases, only 10% (5) had a hospital stay of less than 7 days. CONCLUSION: A high proportion of patients were from rural areas, despite an urbanization rate of more than 90%. In the Campinas region there are two different epidemiological patterns of acquired tetanus: a rural pattern, with a higher proportion of younger patients, determined by an inadequate immunization rate and an urban pattern, similar to that found in industrialized countries, with a higher proportion of older patients. RECOMMENDATIONS: There is an obvious need to immunize older individuals in urban areas and young adults in rural areas. The elimination of acquired tetanus will only be achieved with a wider and more intensive adult vaccination program.INTRODUÇÃO: O número de casos notificados de tétano acidental no Estado de São Paulo sofreu redução. O declínio do número de casos de qualquer doença sempre traz transformações no seu perfil epidemiológico, que devem sempre ser analisadas para aprimorar as medidas preventivas. Assim, foi analisado o perfil clínico e epidemiológico dos casos de tétano internados em hospital universitário de Campinas de 1989 a 1996. MATERIAL E MÉTODO: Estudo descritivo e retrospectivo (série de casos). Todos os pacientes com diagnóstico de tétano de janeiro de 1989 a março de 1996, internados no hospital universitário, foram analisados. RESULTADOS: Catorze (28%) eram da zona rural e 36 (72%) da zona urbana. A idade média foi de 47,6 anos e a mediana de 49,5. Dos pacientes da zona rural, 42,8% tinham até 30 anos e 21,42% tinham mais de 50 anos, sendo a média 36,21 e a mediana 34,5; dos pacientes da zona urbana, 13,9% tinham até 30 anos e 58,3% mais de 50 anos, sendo a média de 52,2 e a mediana de 54,5. A letalidade foi de 20%, mais elevada nos pacientes curarizados (60%). CONCLUSÃO: Na região estudada existem dois padrões epidemiológicos: o rural, com maior número de jovens, refletindo uma vacinação inadequada, e o urbano, semelhante ao dos países desenvolvidos, com predomínio das faixas etárias mais altas

Synthesis and thermochemical study of quinoxaline-N-oxides: enthalpies of dissociation of the N-O bond

The synthesis of three new quinoxaline mono-N-oxides derivatives, namely, 2-tert-butoxycarbonyl-3-methylquinoxaline-N-oxide, 2-phenylcarbamoyl-3-ethylquinoxaline-N-oxide, and 2-carbamoyl-3-methylquinoxaline-N-oxide, from their corresponding 1,4-di-N-oxides is reported. Samples of these compounds were used for a thermochemical study, which allowed derivation of their gaseous standard molar enthalpies of formation, Delta fHmo(g), from their enthalpies of formation in the condensed phase, Delta fHmo(cr), determined by static bomb combustion calorimetry, and from their enthalpies of sublimation, Delta crgHmo, determined by Calvet microcalorimetry. Finally, combining the Delta fHmo(g) for the quinoxaline-N-oxides derived in this work with literature values for the corresponding 1,4-di-N-oxides and atomic oxygen, the bond dissociation enthalpies for cleavage of the first N-O bond in the di-N-oxides, DH1(NO), were obtained and compared with existing data. Copyright (c) 2011 John Wiley & Sons, Ltd

Thermodynamic Properties of Three Pyridine Carboxylic Acid Methyl Ester Isomers

This article discusses the thermodynamic properties of three pyridine carboxylic acid methyl ester isomers

Absorption, partitioning, and export of nutrients by phenological stage in maize cultivated in Eastern Maranhão, Brazil.

This study aimed to evaluate the absorption, partitioning, and redistribution of nutrients by phenological stage of the maize crop, under the edaphoclimatic conditions of the municipality of Brejo, Maranhão, Brazil