The ventilatory response to environmental hypercarbia in the South American rattlesnake, Crotalus durissus

To study the effects of environmental hypercarbia on ventilation in snakes, particularly the anomalous hyperpnea that is seen when CO(2) is removed from inspired gas mixtures (post-hypercapnic hyperpnea), gas mixtures of varying concentrations of CO(2) were administered to South American rattlesnakes, Crotalus durissus, breathing through an intact respiratory system or via a tracheal cannula by-passing the upper airways. Exposure to environmental hypercarbia at increasing levels, up to 7% CO(2), produced a progressive decrease in breathing frequency and increase in tidal volume. The net result was that total ventilation increased modestly, up to 5% CO(2) and then declined slightly on 7% CO(2). on return to breathing air there was an immediate but transient increase in breathing frequency and a further increase in tidal volume that produced a marked overshoot in ventilation. The magnitude of this post-hypercapnic hyperpnea was proportional to the level of previously inspired CO(2). Administration of CO(2) to the lungs alone produced effects that were identical to administration to both lungs and upper airways and this effect was removed by vagotomy. Administration of CO(2) to the upper airways alone was without effect. Systemic injection of boluses of CO(2)-rich blood produced an immediate increase in both breathing frequency and tidal volume. These data indicate that the post-hypercapnic hyperpnea resulted from the removal of inhibitory inputs from pulmonary receptors and suggest that while the ventilatory response to environmental hypercarbia in this species is a result of conflicting inputs from different receptor groups, this does not include input from upper airway receptors.

RESPIRATORY RESPONSES IN A BRAZILIAN MILLIPEDE, PSEUDONANNOLENE-TRICOLOR, TO DECLINING OXYGEN PRESSURES

Oxygen uptake and the influence of declining oxygen pressures (Po2's) were examined in a Brazilian spirostreptid millipede, Pseudonannolene tricolor. The data were obtained in a Warburg respirometer at 25-degrees-C from both male and female animals, sexually inactive, in the intermolt stage, and fasting for 24 h. In a sudden exposure to a decreased Po2 the millipedes regulated respiration down to at least 71 mmHg O2. From a Po2 of 35 mmHg O2 downward the animals started to show oxyconformity. When the millipedes were exposed to a stepwise declining Po2 the results indicated only conformation. After exposure to hypoxia, P. tricolor showed a pattern of underrepayment on return to normoxia, but larger millipedes accumulated more O2 debt than smaller ones.

From Plinthic Acrisols to Plinthosols and Gleysols: iron and groundwater dynamics in the tertiary sediments of the upper Amazon basin

Topography has been reported to be the major factor ruling the spatial distribution of Acrisols, Plinthosols and Gleysols on the seasonally flooded, low elevation plateaux of the upper Amazon basin occupied by Tertiary (Ica & Solimoes) sediments. In this study, detailed morphological and mineralogical investigations conducted in a representative 25-ha site were combined with hydro-geochemical data to relate the vertical and lateral soil differentiations observed to the hydro-geological history of that part of the basin. As a result of the uplift of the Andes, several cuts in the extensive Tertiary marshlands have formed, at first, slightly incised plateaux of low elevation. There, weathering under hot and humid climates would have generated a reddish, freely drained and bioturbated topsoil layer and the vertical differentiation in subsoil sediments of a plinthite over an iron-depleted mottled clay. The second episode of soil differentiation is linked to the replacement of the forest by a savannah under the drier climates of the late Pleistocene, which favours surface runoff and the infill of the incisions by fine particles. This infill, combined with the return to the present humid climate, has then enabled the local groundwater to rise on the plateaux and to generate episaturation at the topsoil/subsoil transition close to the depressions. Nowadays, ferrous iron is released from the partly iron-depleted topsoil weathering front at high water levels during the rainy seasons. It moves from footslope to low-lying positions and from top to bottom in the soil profile according to the groundwater dynamics. The present general trend is thus to the lateral export of iron at high water levels due to subsurface and overland flows, its vertical transfer during the recession of the groundwater and accumulation in a nodular plinthite. In the latter, ferrous iron is adsorbed onto its softest iron masses where it feeds the neoformation of ferrihydrite that rapidly dehydrates into haematite.

If fleas developed a rite, It would be related to the dog

This article highlights a set of Wittgensteinian remarks on James Frazer's texts found in The Golden Bough, put it inside the context of creation of a conceptual framework for his renewed philosophical approach after his return to Cambridge, a period comprehended between 1929-1932, and delimits the ritualistic value of his grammatical method of philosophy.

How to drag with a worn-out mouse? Searching for social justice through collaboration

We consider what a concern for social justice in terms of social inclusion might mean for teacher education, both practising and prospective, with particular reference to the use of information and communication technology (ICT) in mathematics education taking place at a borderland school. Our discussion proceeds through the following steps: (1) We explore what a borderland position might denote to address what social inclusion might mean. (2) We consider the significance of mathematics education and the use of ICT for processes of social inclusion. (3) We briefly refer to the Interlink Network, as many of our observations emerge as reflections on this project. (4) We present different issues that will be of particular importance with respect to teacher education if we want to establish a mathematics education for social inclusion. These issues concern moving away from the comfort zone, establishing networks, identifying new approaches, moving beyond prototypical research, and getting in contact. This brings us to (5) final considerations, where we return to the notion of social justice. © Springer Science+Business Media B.V. 2009.

Structural reforms, macroeconomic fluctuations and income distribution in Brazil

Includes bibliography

Capital flows to Latin America: third quarter 2001

Events in Argentina dominated most of the third quarter of 2001 until September 11, when the terrorist attacks against the United States prompted a sell-off of emerging markets assets, increasing uncertainty and risk aversion against a background of global economic slowdown. Emerging markets' short term prospects to tap international capital markets deteriorated significantly. In the third quarter of 2001, Latin American countries issued US$7.6 billion in bonds, following US$11.2 billion in the second quarter and US$13.2 billion in the first quarter, which had been a jump from only US$2.9 billion in the last quarter of 2000. At first, it seemed that the pace of debt issuance would slow down considerably given Argentina's troubles in July, as Argentina's bond auction at the beginning of the month was poorly received, forcing the government to shorten the maturity of the new debt and to pay rates as high as those during the Russian crisis in 1998. By August, however, emerging markets rebounded strongly on the back of a new US$8 billion IMF assistance package to Argentina, with both Mexico and Brazil successfully launching large issues. International markets displayed considerable flexibility as investors gave Mexico's US$1.5 billion 30- year bond and Brazil's JPY200 billion two-year samurai issue a warm reception. This return to capital markets was interrupted by the events of September 11, which caused debt issuance to fall sharply in September and October. Following the events of September 11, EMBI+ spreads widened above 1,000 basis points for the first time in nearly two years. According to J.P. Morgan there was a 3.7% market decline in September, which brought year-to-date returns for the EMBI+ to only 0.06%. Emerging markets debt, however, fared better than most other fixed income and equity markets in the immediate aftermath of the attacks. U.S. high-yield market suffered its worst month since August 1998, declining by 6.5%, while the S&P 500 and Nasdaq declined by 8.2% and 17%, respectively. Emerging equity markets suffered even greater declines, with losses as severe as 24% in local currency terms and 31% in U.S. dollar terms.

Capital flows to Latin America: fourth quarter 2002

Includes bibliography

Capital flows to Latin America: recent developments

The external environment has deteriorated sharply as a result of the spiraling financial turmoil, and has led to a weakening in commodity prices and fears of a worldwide recession. Latin America and the Caribbean's fastest expansion in 40 years may be threatened as the global credit crunch makes financing scarce and squeezes demand for the region's commodities. This time around the region is better positioned to weather the crisis than in the past, given improvements in macroeconomic and financial policies as well as a reduced net dependency on external capital inflows. However, Latin American markets are feeling the effects of the crisis through a slowdown in capital inflows, large declines in stock price indexes, significant currency adjustments and an increase in debt spreads. Volatility has soared, with the closely watched Chicago Board Options Exchange Volatility Index moving to an all-time high of 70.33 on October 17, indicating that fear (rather than greed) has been ruling the markets.After reaching record lows in May 2007, emerging markets bond spreads are now above pre-Asian crisis levels. The JPMorgan EMBI+ Latin American composite widened by 146 basis points in the third quarter, with spreads reaching 448 basis points at the end of September. Spreads have widened sharply in recent weeks as foreign investors cut back regional exposure for the safety of U.S. Treasuries. The ongoing lack of liquidity and subsequent liquidation of assets is leading to a collapse in asset prices and a sharp widening in spreads. Daily spreads in October have risen to levels not seen since December 2002, making it much more difficult for governments that need financing to get it. Risk premiums for Latin corporates and sovereigns have risen substantially, but have remained well below U.S. junk (high-yield) bonds. Latin corporates are facing a steep rise in foreign exchange borrowing costs (although less than firms in other emerging markets), which raises concerns that refinancing risks will climb.So far, emerging markets vulnerabilities have been more focused on corporates, as sovereigns have improved public debt dynamics and countries' financing needs are under control. Market performance has been driven by the rapid deterioration of emerging markets bank and corporate market, as well as ongoing losses in emerging markets equities. From January to September 2008, the Morgan Stanley Capital International (MSCI) Latin American Index lost almost 28%, while the Emerging Markets Index lost 37% and the G-7 Index lost 24%. While in 2007 the Latin America component gained 47%, almost nine times as much as the MSCI-G7 index for developed markets, since mid-September 2008 stocks in Latin America have been doing worse than stocks in developed countries, as concerns about access to credit and the adverse impact of sharp falls in commodity prices and in local currencies contribute to increased risk aversion and to outflows of capital. Many governments in the region have used revenue from the commodity boom to pay down debt and build reserves. Now, facing a global financial crisis and the threat of recession in developed countries, the biggest question for Latin America is how long and deep this cyclical downturn will be, and how much it is going to reduce commodity prices. Prices for commodities such as soy, gold, copper and oil, which helped fund the region's boom, have fallen 28% since their July 2 high, according to the RJ/CRB Commodity Price Index. According to Morgan Stanley (in a September 29 report), should prices return to their 10-year average, Latin America's balanced budgets would quickly revert to a deficit of 4.1% of GDP. As risk aversion increases, investors are rapidly pulling out massive amounts of money, creating problems for local markets and banks. There is an ongoing shortage of dollars (as investors liquidate assets in Latin American markets), and as currencies depreciate, inflation concerns increase despite the global slowdown. In Brazil and Mexico, central banks deployed billions of dollars of reserves to stem steep currency declines, as companies in these countries, believing their local currencies would continue to strengthen against the U.S. dollar, took debts in dollars. Some companies also made bets using currency derivatives that have led to losses in the billions of dollars. Dramatic currency swings have caused heavy losses for many companies, from Mexico's cement giant Cemex SAB to the Brazilian conglomerate Grupo Votorantim. Mexico's third-largest retailer, Controladora Comercial Mexicana, declared bankruptcy recently after reporting huge losses related to exchange rate bets. As concerns about corporate exposure to dollar-denominated derivatives increases, yields on bonds issued by many of Brazil's and Mexico's leading companies have started to rise, sharply raising the cost of issuing new debt. Latin American external debt issuance came to a halt in the third quarter of 2008, totaling only US$ 690 million. The cost of obtaining loans for capital expenditures, M&A and debt refinancing is also rising substantially for Latin American corporates amid contagion from the U.S. financial crisis. According to bankers, a protracted trend of shortening tenors and widening spreads has intensified in the past few weeks, indicating that bank lending is quickly following the way of bonds and equity. Finally, money transfers from Latin American migrants are expected to decline for the first time this decade, as a result of economic downturns in the U.S. and Spain, inflation and a weaker dollar. The Mexican Central Bank announced that money transfers from Mexicans living in the U.S. dropped a record 12.2% in August. In 2008, migrants from the region will send some 1.7% less in remittances year-on-year when adjusted for inflation, according to the IADB, compounding the adverse effects of the deepening financial turmoil.

Non-specific immune parameters and physiological response of Nile tilapia fed beta-glucan and vitamin C for different periods and submitted to stress and bacterial challenge

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Transrectal bladder prolapse secondary to pelvic fracture in two dogs

This report describes the exteriorisation of the urinary bladder in two dogs as a result of a laceration of the rectum from a traumatic pelvic fracture. Clinical examination and contrast radiography of the bladder were used as diagnostic tools. Both patients were treated with exploratory laparotomy, where traction of the bladder was utilised to pull the bladder through the traumatic rectal laceration allowing the organ to return to its normal anatomical position. This procedure was followed by surgical reconstruction of the rectum, resulting in effective resolution of each case.

Respiratory responses of the tropical millipede Plusioporus setiger (Broelemann, 1902) (Spirostreptida: Spirostreptidae) to normoxic and hypoxic conditions

1. 1. Oxygen consumption and its relationship to declining oxygen tension was examined in the tropical spirotreptid millipede, Plusioporus setiger. 2. 2. At 25°C and normoxia, the allometric equations relating the weight-specific oxygen consumption rates and body weight were V ̇O2 = 2.1266 × W-53 for males, and V ̇O2 = 2.0915 × W-64 for females, but no significant difference was detected from the b-values. 3. 3. Plusioporus setiger regulated respiration down to 35.40 mmHg O2 when suddenly exposed to a lowered oxygen tension, or 17.70 mmHg O2, when examined in a stepwise declining oxygen tension. 4. 4. O2 dependence indices ( K1 K2) were relatively low, also expressing regulation, but no relation to size (weight) was recorded. 5. 5. After exposure to hypoxia, P. setiger showed a typical pattern of under repayment, on the return to normoxia. © 1987.

Provisioning Strategies of Antarctic Fur Seals and Chinstrap Penguins Produce Different Responses to Distribution of Common Prey and Habitat

Central-place foragers that must return to a breeding site to deliver food to offspring are faced with trade-offs between prey patch quality and distance from the colony. Among colonial animals, pinnipeds and seabirds may have different provisioning strategies, due to differences in their ability to travel and store energy. We compared the foraging areas of lactating Antarctic fur seals and chinstrap penguins breeding at Seal Island, Antarctica, to investigate whether they responded differently to the distribution of their prey (Antarctic krill and myctophid fish) and spatial heterogeneity in their habitat. Dense krill concentrations occurred in the shelf region near the colony. However, only brooding penguins, which are expected to be time-minimizers because they must return frequently with whole food for their chicks, foraged mainly in this proximal shelf region. Lactating fur seals and incubating penguins, which can make longer trips to increase energy gain per trip, and so are expected to be energy-maximizers, foraged in the more distant (>20 km from the island) slope and oceanic regions. The shelf region was characterized by more abundant, but lower-energy-content immature krill, whereas the slope and oceanic regions had less abundant but higher-energy-content gravid krill, as well as high-energy-content myctophids. Furthermore, krill in the shelf region undertook diurnal vertical migration, whereas those in the slope and oceanic regions stayed near the surface throughout the day, which may enhance the capture rate for visual predators. Therefore, we sug- gest that the energy-maximizers foraged in distant, but potentially more profitable feeding regions, while the time-minimizers foraged in closer, but potentially less profitable regions. Thus, time and energy constraints derived from different provisioning strategies may result in sympatric colonial predator species using different foraging areas, and as a result, some central-place foragers use sub- optimal foraging habitats, in terms of the quality or quantity of available prey.

Comparison of Endocrine Response to Stress Between Captive-Raised and Wild-Caught Bighorn Sheep

Stress hormones in Rocky Mountain bighorn sheep (Ovis canadensis canadensis), produced in response to environmental changes, road development, or high population density, may impact their immune systems to a threshold level that predisposes them to periodic, large-scale mortality. We compared the stress response to a novel environmental situation and repeated handling between bighorn sheep born and raised in captivity (CR) and bighorn sheep born in the wild (WC) and brought into captivity. We measured plasma epinephrine, norepinephrine, cortisol, and fecal glucocorticoid metabolites (FGM). Three weeks after each group’s arrival we used a one-time drop-net event to elicit an acute stress response, and we collected blood samples from each sheep over 35 minutes, as well as one fecal sample. We collected blood and fecal samples from both groups on 7 other occasions over the subsequent 6 months. We also collected fecal samples from the pen at approximately 24-hour intervals for 3 days following every handling event to monitor the stress response to handling. We found that CR sheep had a stronger autonomic nervous system response than WC sheep, as measured by epinephrine and norepinephrine levels, but we found a very similar hypothalamic–pituitary–adrenal axis (HPA) response, measured by cortisol levels, to the acute stress event of a drop-net restraint. We also found that once the WC sheep had acclimated, as indicated by the return to the initial baseline FGM levels within 12 weeks, the CR and WC groups’ HPA responses to sampling events were not significantly different from one another. Fecal samples can provide a noninvasive mechanism for managers to monitor baseline FGM for a given herd. Using long-term monitoring of FGM rather than values from a single point in time may allow managers to correlate these levels to outside influences on the herd and better understand the impacts of management changes, population density, or increased human developments on the health of the sheep population.

EXPERIMENTAL TREE TRIMMING TO CONTROL AN URBAN WINTER BLACKBIRD ROOST

Every fall millions of blackbirds come down the Mississippi Flyway to return to their winter roosts in Arkansas, Louisiana, and East Texas. When these roosts are located in urban areas, public pressure makes the more common chemical means of control impractical. A less destructive and more permanent method of control was sought. At Rice University, in Houston, Texas, there has been a blackbird roost of various sizes and durations since 1956. For the past two years we have had the opportunity both to study roosting blackbird biology and experiment with habitat alteration as a control method. This particular report concentrates on the results and interpretation of the tree- trimming program initiated in August 1974. The birds involved are primarily Brown-headed Cowbirds (Molothrus ater), along with Starlings (sturnus vulgaris), Common and Great-tailed Grackles (Quiscalus quiscula and Cassidix mexicanus), Red-winged Blackbirds (Agelaius phoenicus) and Robins (Turdus migratorius). The campus comprises 121 ha and was planted with live oaks (Quercus virginiana) in 1912. These trees retain their foliage throughout the winter and now form a closed canopy over some 5-6 ha. In the 60s and early 70s most of the birds that came to Houston for the winter roosted in a 64-ha woodlot 10 km north of campus. In January 1970, the U.S. Fish and Wildlife Roosting Survey reported one million birds at this site we call the North Loop. Fifteen- thousand birds were estimated at Rice.