Chemical and aerosol characterisation of the troposphere over West Africa during the monsoon period as part of AMMA

During June, July and August 2006 five aircraft took part in a campaign over West Africa to observe the aerosol content and chemical composition of the troposphere and lower stratosphere as part of the African Monsoon Multidisciplinary Analysis (AMMA) project. These are the first such measurements in this region during the monsoon period. In addition to providing an overview of the tropospheric composition, this paper provides a description of the measurement strategy (flights performed, instrumental payloads, wing-tip to wing-tip comparisons) and points to some of the important findings discussed in more detail in other papers in this special issue. The ozone data exhibits an "S" shaped vertical profile which appears to result from significant losses in the lower troposphere due to rapid deposition to forested areas and photochemical destruction in the moist monsoon air, and convective uplift of ozone-poor air to the upper troposphere. This profile is disturbed, particularly in the south of the region, by the intrusions in the lower and middle troposphere of air from the southern hemisphere impacted by biomass burning. Comparisons with longer term data sets suggest the impact of these intrusions on West Africa in 2006 was greater than in other recent wet seasons. There is evidence for net photochemical production of ozone in these biomass burning plumes as well as in urban plumes, in particular that from Lagos, convective outflow in the upper troposphere and in boundary layer air affected by nitrogen oxide emissions from recently wetted soils. This latter effect, along with enhanced deposition to the forested areas, contributes to a latitudinal gradient of ozone in the lower troposphere. Biogenic volatile organic compounds are also important in defining the composition both for the boundary layer and upper tropospheric convective outflow. Mineral dust was found to be the most abundant and ubiquitous aerosol type in the atmosphere over Western Africa. Data collected within AMMA indicate that injection of dust to altitudes favourable for long-range transport (i.e. in the upper Sahelian planetary boundary layer) can occur behind the leading edge of mesoscale convective system (MCS) cold-pools. Research within AMMA also provides the first estimates of secondary organic aerosols across the West African Sahel and have shown that organic mass loadings vary between 0 and 2 μg m−3 with a median concentration of 1.07 μg m−3. The vertical distribution of nucleation mode particle concentrations reveals that significant and fairly strong particle formation events did occur for a considerable fraction of measurement time above 8 km (and only there). Very low concentrations were observed in general in the fresh outflow of active MCSs, likely as the result of efficient wet removal of aerosol particles due to heavy precipitation inside the convective cells of the MCSs. This wet removal initially affects all particle size ranges as clearly shown by all measurements in the vicinity of MCSs.

Report of the 2010 assessment of the scientific assessment panel: future ozone and its impact on surface UV

SCIENTIFIC SUMMARY Globally averaged total column ozone has declined over recent decades due to the release of ozone-depleting substances (ODSs) into the atmosphere. Now, as a result of the Montreal Protocol, ozone is expected to recover from the effects of ODSs as ODS abundances decline in the coming decades. However, a number of factors in addition to ODSs have led to and will continue to lead to changes in ozone. Discriminating between the causes of past and projected ozone changes is necessary, not only to identify the progress in ozone recovery from ODSs, but also to evaluate the effectiveness of climate and ozone protection policy options. Factors Affecting Future Ozone and Surface Ultraviolet Radiation • At least for the next few decades, the decline of ODSs is expected to be the major factor affecting the anticipated increase in global total column ozone. However, several factors other than ODS will affect the future evolution of ozone in the stratosphere. These include changes in (i) stratospheric circulation and temperature due to changes in long-lived greenhouse gas (GHG) abundances, (ii) stratospheric aerosol loading, and (iii) source gases of highly reactive stratospheric hydrogen and nitrogen compounds. Factors that amplify the effects of ODSs on ozone (e.g., stratospheric aerosols) will likely decline in importance as ODSs are gradually eliminated from the atmosphere. • Increases in GHG emissions can both positively and negatively affect ozone. Carbon dioxide (CO2)-induced stratospheric cooling elevates middle and upper stratospheric ozone and decreases the time taken for ozone to return to 1980 levels, while projected GHG-induced increases in tropical upwelling decrease ozone in the tropical lower stratosphere and increase ozone in the extratropics. Increases in nitrous oxide (N2O) and methane (CH4) concentrations also directly impact ozone chemistry but the effects are different in different regions. • The Brewer-Dobson circulation (BDC) is projected to strengthen over the 21st century and thereby affect ozone amounts. Climate models consistently predict an acceleration of the BDC or, more specifically, of the upwelling mass flux in the tropical lower stratosphere of around 2% per decade as a consequence of GHG abundance increases. A stronger BDC would decrease the abundance of tropical lower stratospheric ozone, increase poleward transport of ozone, and could reduce the atmospheric lifetimes of long-lived ODSs and other trace gases. While simulations showing faster ascent in the tropical lower stratosphere to date are a robust feature of chemistry-climate models (CCMs), this has not been confirmed by observations and the responsible mechanisms remain unclear. • Substantial ozone losses could occur if stratospheric aerosol loading were to increase in the next few decades, while halogen levels are high. Stratospheric aerosol increases may be caused by sulfur contained in volcanic plumes entering the stratosphere or from human activities. The latter might include attempts to geoengineer the climate system by enhancing the stratospheric aerosol layer. The ozone losses mostly result from enhanced heterogeneous chemistry on stratospheric aerosols. Enhanced aerosol heating within the stratosphere also leads to changes in temperature and circulation that affect ozone. • Surface ultraviolet (UV) levels will not be affected solely by ozone changes but also by the effects of climate change and by air quality change in the troposphere. These tropospheric effects include changes in clouds, tropospheric aerosols, surface reflectivity, and tropospheric sulfur dioxide (SO2) and nitrogen dioxide (NO2). The uncertainties in projections of these factors are large. Projected increases in tropospheric ozone are more certain and may lead to reductions in surface erythemal (“sunburning”) irradiance of up to 10% by 2100. Changes in clouds may lead to decreases or increases in surface erythemal irradiance of up to 15% depending on latitude. Expected Future Changes in Ozone Full ozone recovery from the effects of ODSs and return of ozone to historical levels are not synonymous. In this chapter a key target date is chosen to be 1980, in part to retain the connection to previous Ozone Assessments. Noting, however, that decreases in ozone may have occurred in some regions of the atmosphere prior to 1980, 1960 return dates are also reported. The projections reported on in this chapter are taken from a recent compilation of CCM simulations. The ozone projections, which also form the basis for the UV projections, are limited in their representativeness of possible futures since they mostly come from CCM simulations based on a single GHG emissions scenario (scenario A1B of Emissions Scenarios. A Special Report of Working Group III of the Intergovernmental Panel on Climate Change, Cambridge University Press, 2000) and a single ODS emissions scenario (adjusted A1 of the previous (2006) Ozone Assessment). Throughout this century, the vertical, latitudinal, and seasonal structure of the ozone distribution will be different from what it was in 1980. For this reason, ozone changes in different regions of the atmosphere are considered separately. • The projections of changes in ozone and surface clear-sky UV are broadly consistent with those reported on in the 2006 Assessment. • The capability of making projections and attribution of future ozone changes has been improved since the 2006 Assessment. Use of CCM simulations from an increased number of models extending through the entire period of ozone depletion and recovery from ODSs (1960–2100) as well as sensitivity simulations have allowed more robust projections of long-term changes in the stratosphere and of the relative contributions of ODSs and GHGs to those changes. • Global annually averaged total column ozone is projected to return to 1980 levels before the middle of the century and earlier than when stratospheric halogen loading returns to 1980 levels. CCM projections suggest that this early return is primarily a result of GHG-induced cooling of the upper stratosphere because the effects of circulation changes on tropical and extratropical ozone largely cancel. Global (90°S–90°N) annually averaged total column ozone will likely return to 1980 levels between 2025 and 2040, well before the return of stratospheric halogens to 1980 levels between 2045 and 2060. • Simulated changes in tropical total column ozone from 1960 to 2100 are generally small. The evolution of tropical total column ozone in models depends on the balance between upper stratospheric increases and lower stratospheric decreases. The upper stratospheric increases result from declining ODSs and a slowing of ozone destruction resulting from GHG-induced cooling. Ozone decreases in the lower stratosphere mainly result from an increase in tropical upwelling. From 1960 until around 2000, a general decline is simulated, followed by a gradual increase to values typical of 1980 by midcentury. Thereafter, although total column ozone amounts decline slightly again toward the end of the century, by 2080 they are no longer expected to be affected by ODSs. Confidence in tropical ozone projections is compromised by the fact that simulated decreases in column ozone to date are not supported by observations, suggesting that significant uncertainties remain. • Midlatitude total column ozone is simulated to evolve differently in the two hemispheres. Over northern midlatitudes, annually averaged total column ozone is projected to return to 1980 values between 2015 and 2030, while for southern midlatitudes the return to 1980 values is projected to occur between 2030 and 2040. The more rapid return to 1980 values in northern midlatitudes is linked to a more pronounced strengthening of the poleward transport of ozone due to the effects of increased GHG levels, and effects of Antarctic ozone depletion on southern midlatitudes. By 2100, midlatitude total column ozone is projected to be above 1980 values in both hemispheres. • October-mean Antarctic total column ozone is projected to return to 1980 levels after midcentury, later than in any other region, and yet earlier than when stratospheric halogen loading is projected to return to 1980 levels. The slightly earlier return of ozone to 1980 levels (2045–2060) results primarily from upper stratospheric cooling and resultant increases in ozone. The return of polar halogen loading to 1980 levels (2050–2070) in CCMs is earlier than in empirical models that exclude the effects of GHG-induced changes in circulation. Our confidence in the drivers of changes in Antarctic ozone is higher than for other regions because (i) ODSs exert a strong influence on Antarctic ozone, (ii) the effects of changes in GHG abundances are comparatively small, and (iii) projections of ODS emissions are more certain than those for GHGs. Small Antarctic ozone holes (areas of ozone <220 Dobson units, DU) could persist to the end of the 21st century. • March-mean Arctic total column ozone is projected to return to 1980 levels two to three decades before polar halogen loading returns to 1980 levels, and to exceed 1980 levels thereafter. While CCM simulations project a return to 1980 levels between 2020 and 2035, most models tend not to capture observed low temperatures and thus underestimate present-day Arctic ozone loss such that it is possible that this return date is biased early. Since the strengthening of the Brewer-Dobson circulation through the 21st century leads to increases in springtime Arctic column ozone, by 2100 Arctic ozone is projected to lie well above 1960 levels. Uncertainties in Projections • Conclusions dependent on future GHG levels are less certain than those dependent on future ODS levels since ODS emissions are controlled by the Montreal Protocol. For the six GHG scenarios considered by a few CCMs, the simulated differences in stratospheric column ozone over the second half of the 21st century are largest in the northern midlatitudes and the Arctic, with maximum differences of 20–40 DU between the six scenarios in 2100. • There remain sources of uncertainty in the CCM simulations. These include the use of prescribed ODS mixing ratios instead of emission fluxes as lower boundary conditions, the range of sea surface temperatures and sea ice concentrations, missing tropospheric chemistry, model parameterizations, and model climate sensitivity. • Geoengineering schemes for mitigating climate change by continuous injections of sulfur-containing compounds into the stratosphere, if implemented, would substantially affect stratospheric ozone, particularly in polar regions. Ozone losses observed following large volcanic eruptions support this prediction. However, sporadic volcanic eruptions provide limited analogs to the effects of continuous sulfur emissions. Preliminary model simulations reveal large uncertainties in assessing the effects of continuous sulfur injections. Expected Future Changes in Surface UV. While a number of factors, in addition to ozone, affect surface UV irradiance, the focus in this chapter is on the effects of changes in stratospheric ozone on surface UV. For this reason, clear-sky surface UV irradiance is calculated from ozone projections from CCMs. • Projected increases in midlatitude ozone abundances during the 21st century, in the absence of changes in other factors, in particular clouds, tropospheric aerosols, and air pollutants, will result in decreases in surface UV irradiance. Clear-sky erythemal irradiance is projected to return to 1980 levels on average in 2025 for the northern midlatitudes, and in 2035 for the southern midlatitudes, and to fall well below 1980 values by the second half of the century. However, actual changes in surface UV will be affected by a number of factors other than ozone. • In the absence of changes in other factors, changes in tropical surface UV will be small because changes in tropical total column ozone are projected to be small. By the middle of the 21st century, the model projections suggest surface UV to be slightly higher than in the 1960s, very close to values in 1980, and slightly lower than in 2000. The projected decrease in tropical total column ozone through the latter half of the century will likely result in clear-sky surface UV remaining above 1960 levels. Average UV irradiance is already high in the tropics due to naturally occurring low total ozone columns and high solar elevations. • The magnitude of UV changes in the polar regions is larger than elsewhere because ozone changes in polar regions are larger. For the next decades, surface clear-sky UV irradiance, particularly in the Antarctic, will continue to be higher than in 1980. Future increases in ozone and decreases in clear-sky UV will occur at slower rates than those associated with the ozone decreases and UV increases that occurred before 2000. In Antarctica, surface clear-sky UV is projected to return to 1980 levels between 2040 and 2060, while in the Arctic this is projected to occur between 2020 and 2030. By 2100, October surface clear-sky erythemal irradiance in Antarctica is likely to be between 5% below to 25% above 1960 levels, with considerable uncertainty. This is consistent with multi-model-mean October Antarctic total column ozone not returning to 1960 levels by 2100. In contrast, by 2100, surface clear-sky UV in the Arctic is projected to be 0–10% below 1960 levels.

Evidence for changes in stratospheric transport and mixing over the past three decades based on multiple data sets and tropical leaky pipe analysis

Variability in the strength of the stratospheric Lagrangian mean meridional or Brewer-Dobson circulation and horizontal mixing into the tropics over the past three decades are examined using observations of stratospheric mean age of air and ozone. We use a simple representation of the stratosphere, the tropical leaky pipe (TLP) model, guided by mean meridional circulation and horizontal mixing changes in several reanalyses data sets and chemistry climate model (CCM) simulations, to help elucidate reasons for the observed changes in stratospheric mean age and ozone. We find that the TLP model is able to accurately simulate multiyear variability in ozone following recent major volcanic eruptions and the early 2000s sea surface temperature changes, as well as the lasting impact on mean age of relatively short-term circulation perturbations. We also find that the best quantitative agreement with the observed mean age and ozone trends over the past three decades is found assuming a small strengthening of the mean circulation in the lower stratosphere, a moderate weakening of the mean circulation in the middle and upper stratosphere, and a moderate increase in the horizontal mixing into the tropics. The mean age trends are strongly sensitive to trends in the horizontal mixing into the tropics, and the uncertainty in the mixing trends causes uncertainty in the mean circulation trends. Comparisons of the mean circulation and mixing changes suggested by the measurements with those from a recent suite of CCM runs reveal significant differences that may have important implications on the accurate simulation of future stratospheric climate.

Analysis and modeling of active occupancy of the residential sector in Spain: an indicator of residential electricity consumption

The growing energy consumption in the residential sector represents about 30% of global demand. This calls for Demand Side Management solutions propelling change in behaviors of end consumers, with the aim to reduce overall consumption as well as shift it to periods in which demand is lower and where the cost of generating energy is lower. Demand Side Management solutions require detailed knowledge about the patterns of energy consumption. The profile of electricity demand in the residential sector is highly correlated with the time of active occupancy of the dwellings; therefore in this study the occupancy patterns in Spanish properties was determined using the 2009–2010 Time Use Survey (TUS), conducted by the National Statistical Institute of Spain. The survey identifies three peaks in active occupancy, which coincide with morning, noon and evening. This information has been used to input into a stochastic model which generates active occupancy profiles of dwellings, with the aim to simulate domestic electricity consumption. TUS data were also used to identify which appliance-related activities could be considered for Demand Side Management solutions during the three peaks of occupancy.

The role of anomalous SST and surface fluxes over the Southeastern North Atlantic in the explosive development of windstorm Xynthia

In late February 2010 the extraordinary windstorm Xynthia crossed over Southwestern and Central Europe and caused severe damage, affecting particularly the Spanish and French Atlantic coasts. The storm was embedded in uncommon large-scale atmospheric and boundary conditions prior to and during its development, namely enhanced sea surface temperatures (SST) within the low-level entrainment zone of air masses, an unusual southerly position of the polar jet stream, and a remarkable split jet structure in the upper troposphere. To analyse the processes that led to the rapid intensification of this exceptional storm originating close to the subtropics (30°N), the sensitivity of the cyclone intensification to latent heat release is determined using the regional climate model COSMO-CLM forced with ERA-Interim data. A control simulation with observed SST shows that moist and warm air masses originating from the subtropical North Atlantic were involved in the cyclogenesis process and led to the formation of a vertical tower with high values of potential vorticity (PV). Sensitivity studies with reduced SST or increased laminar boundary roughness for heat led to reduced surface latent heat fluxes. This induced both a weaker and partly retarded development of the cyclone and a weakening of the PV-tower together with reduced diabatic heating rates, particularly at lower and mid levels. We infer that diabatic processes played a crucial role during the phase of rapid deepening of Xynthia and thus to its intensity over the Southeastern North Atlantic. We suggest that windstorms like Xynthia may occur more frequently under future climate conditions due to the warming SSTs and potentially enhanced latent heat release, thus increasing the windstorm risk for Southwestern Europe.

Timing and depositional environments of a Middle Pleistocene glaciation of northeast England: New evidence from Warren House Gill, County Durham

At various times during the Quaternary, north-eastern England was a zone of confluence between dynamic ice lobes sourced from the Pennines, northern Scotland, the Cheviots, and Scandinavia. The region thus has some of the most complex exposures of Middle to Late Pleistocene sediments in Britain, with both interglacial and glacial sediments deposited in terrestrial and marine settings. We investigated sedimentary sequences exposed on the coastline of County Durham at Warren House Gill, and present a new model of British and Fennoscandian Ice Sheet interaction in the North Sea Basin during the Middle Pleistocene. The stratigraphy at Warren House Gill consists of a lower diamicton and upper estuarine sediments, both part of the Warren House Formation. They are separated from the overlying Weichselian Blackhall and Horden tills by a substantial unconformity. The lower diamicton of the Warren House Formation is re-interpreted here as an MIS 8 to 12 glaciomarine deposit containing ice-rafted lithics from north-eastern Scotland and the northeast North Sea, and is renamed the ‘Ash Gill Member’. It is dated by lithological comparison to the Easington Raised Beach, Middle Pleistocene Amino Acid Racemisation values, and indirectly by optically stimulated luminescence. The overlying shallow subaqueous sediments were deposited in an estuarine environment by suspension settling and bottom current activity. They are named the ‘Whitesides Member’, and form the uppermost member of the Warren House Formation. During glaciation, ice-rafted material was deposited in a marine embayment. There is no evidence of a grounded, onshore Scandinavian ice sheet in County Durham during MIS 6, which has long been held as the accepted stratigraphy. This has major implications for the currently accepted British Quaternary Stratigraphy. Combined with recent work on the Middle Pleistocene North Sea Drift from Norfolk, which is now suggested to have been deposited by a Scottish ice sheet, the presence of a Scandinavian ice sheet in eastern England at any time during the Quaternary is becoming increasingly doubtful.

Genetic algorithm inversion of the average 1D crustal structure using local and regional earthquakes

Knowing the best 1D model of the crustal and upper mantle structure is useful not only for routine hypocenter determination, but also for linearized joint inversions of hypocenters and 3D crustal structure, where a good choice of the initial model can be very important. Here, we tested the combination of a simple GA inversion with the widely used HYPO71 program to find the best three-layer model (upper crust, lower crust, and upper mantle) by minimizing the overall P- and S-arrival residuals, using local and regional earthquakes in two areas of the Brazilian shield. Results from the Tocantins Province (Central Brazil) and the southern border of the Sao Francisco craton (SE Brazil) indicated an average crustal thickness of 38 and 43 km, respectively, consistent with previous estimates from receiver functions and seismic refraction lines. The GA + HYPO71 inversion produced correct Vp/Vs ratios (1.73 and 1.71, respectively), as expected from Wadati diagrams. Tests with synthetic data showed that the method is robust for the crustal thickness, Pn velocity, and Vp/Vs ratio when using events with distance up to about 400 km, despite the small number of events available (7 and 22, respectively). The velocities of the upper and lower crusts, however, are less well constrained. Interestingly, in the Tocantins Province, the GA + HYPO71 inversion showed a secondary solution (local minimum) for the average crustal thickness, besides the global minimum solution, which was caused by the existence of two distinct domains in the Central Brazil with very different crustal thicknesses. (C) 2010 Elsevier Ltd. All rights reserved.

Branch and Bound Algorithm for Multiprocessor Scheduling

The multiprocessor task graph scheduling problem has been extensively studied asacademic optimization problem which occurs in optimizing the execution time of parallelalgorithm with parallel computer. The problem is already being known as one of the NPhardproblems. There are many good approaches made with many optimizing algorithmto find out the optimum solution for this problem with less computational time. One ofthem is branch and bound algorithm.In this paper, we propose a branch and bound algorithm for the multiprocessor schedulingproblem. We investigate the algorithm by comparing two different lower bounds withtheir computational costs and the size of the pruned tree.Several experiments are made with small set of problems and results are compared indifferent sections.

Population structure of pond-raised Macrobrachium amazonicum with different stocking and harvesting strategies

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

Spontaneous Blinking in Patients With Graves' Upper Eyelid Retraction

Purpose: To describe spontaneous blink kinematics in Graves' upper eyelid retraction (UER).Methods: The magnetic search coil technique was used to record spontaneous blinks of 15 healthy subjects (aged 23-56 years, 15 eyelids) and 15 patients with Graves' UER (aged 22-62 years, 15 eyelids) during a 5-min period of video observation, and the signals were digitized at 200 Hz (12 bits). Overall, a total of 2,798 blinks were recorded for the controls and 1,860 for the patients. The distance between pupil center and upper eyelid margin in the primary position of gaze (MRD) was measured with the Image J software.Results: The blinking rate of patients was lower than that of control subjects, with a mean (+/-SEM) blinking rate (blinks/min) of 13.0 +/- 1.7 for patients and of 20.0 +/- 2.1 for the controls (t = 2.58, P = 0.016). There were no statistically significant differences in blink amplitude between controls (22.7 +/- 3.1 degrees) and Graves' patients (24.7 +/- 3.3 degrees). However, while only 22% of the blinks performed by controls were smaller than MRD, this rate was 78% for patients. In addition, in blinks larger than 25, patients showed lower down-phase velocity than controls.Conclusions: Patients with Graves' UER show reduced blinks rates and abnormal blink kinematics, which might be related to the development of exposure keratitis in this disease.

Ultrastructural morphology and morphometry of the normal corneal endothelium of adult crossbred pig

O endotélio corneal é uma monocamada de células poligonais. A integridade e saúde dessa camada são essenciais para a manutenção da transparência corneal normal. Este estudo reportou pela primeira vez, de forma detalhada, a morfologia ultra-estrutural e a morfometria do endotélio corneal de suínos adultos mestiços à microscopia eletrônica de varredura (MEV). A superfície endothelial corneal apresentou um padrão regular de células poligonais, com predomínio da forma hexagonal e de bordas celulares nítidas. O núcleo foi observado como protuberância arredondada no centro da célula. Também foram observados os cílios (2-4) em apenas algumas células da região periférica da córnea, as aberturas das vesículas pinocitóticas na proximidade dos cílios, as microvilosidades, as varas da borda e as bordas celulares em formato de zigzag. A área celular média foi significativamente maior (P<0,05) no centro da córnea do que na periferia, com um coeficiente de variação menor no centro da córnea. A densidade celular média foi significativamente maior na periferia (P<0,05) e 43,9% maior que os dados reportados por outros autores na microscopia especular, o que demonstra o efeito da retração celular durante o processamento das amostras. O valor médio do número de lados das células (pleomorfismo) foi de 5,9, o que evidencia um predomínio do formato hexagonal. A percentagem de células hexagonais foi significativamente maior no centro (P<0,001). Os parâmetros obtidos nesta pesquisa servirão de base para estudos futuros sobre o efeito de medicamentos, cirurgias intracamerulares ou soluções para armazenamento de córneas para transplantes no endotélio corneal do suíno.

Phosphate forms in plant and their internal buffering in five soybean cultivars

Diferenças inter e intra-específicas na habilidade de suportar períodos de estresse nutricional podem dever-se à capacidade de armazenar e liberar íons dos vacúolos, e, ou, à intensidade de retranslocação de nutrientes em tais condições. Neste trabalho, pretendeu-se avaliar diferenças varietais quanto ao tamanho do pool não-metabólico de Pi; velocidade de liberação do Pi previamente armazenado (VLPi), quando o P citoplasmático cai a um valor limite; capacidade de transportar Pi de regiões menos ativas para aquelas mais ativas metabolicamente e definir compartimentos que são preferencialmente fontes e os que são preferencialmente drenos para o Pi, em condições de absorção limitada de P. Avaliaram-se a produção de matéria seca e os teores internos de Pi, orgânico (Po) e total solúvel em ácido (Pts), de diferentes órgãos de plantas dos cultivares de soja (Glycine max L. Merrill) Santa Rosa, Uberaba, IAC8, Doko e UFV1, submetidos a oito dias de omissão do elemento. A VLPi foi estimada como tangente às equações obtidas para Pi como função do perído de omissão no ponto médio do período de omissão em que houve maior decréscimo em Pi (zero a quatro dias de omissão de P), t = dois dias, considerando-se que -deltaPi/deltat expressa a velocidade de liberação de Pi. A capacidade interna de tamponamento de Pi (CTIPi) foi calculada como o inverso da VLPi. O cultivar Santa Rosa apresentou maior capacidade de armazenar Pi, quando o suprimento externo foi alto, liberando-o mais intensamente sob condições de baixo suprimento de P que os cultivares IAC8 e UFV1. O cultivar Uberaba mostrou-se superior ao Doko em sua habilidade de armazenar e utilizar o Pi. Folhas superiores mostraram ser o principal dreno para o Pi armazenado em folhas medianas e inferiores, seguidas por raízes e caules. Raízes comportaram-se como fontes ou drenos para o Pi. Raízes e folhas superiores apresentaram maiores (VLPi) e menores valores de CTIPi que folhas medianas e folhas inferiores, sendo o caule o compartimento com menor VLPi e maior CTIPi. Dentre as variedades, as diferenças foram pequenas, destacando-se a maior VLPi e menor CTIPi do cultivar Santa Rosa. O cultivar Doko apresentou a menor VLPi e maior CTIPi, enquanto Uberaba, IAC8 e UFV1 ocuparam posição intermediária quanto a essas características.

Adsorption of Cu(II) and Co(II) complexes on a silica gel surface chemically modified with 2-mercaptoimidazole

The isotherms of adsorption of MeX2 (Me = Cu2+, Co2+; X = Cl-, Br-, ClO4-) by silica gel chemically modified with 2-mercaptoimidazole (SiMI) were studied in acetone and ethanol solutions, at 25 degrees C. Covalently attached 2-mercaptoimidazole molecule to silica gel surface adsorbs MeX2 from solvent by forming a surface complex. The metal is bonded to the surface through the nitrogen atom of attached 2-mercaptoimidazole. At low loading, the electronic and ESR spectral parameters indicated that the Cu2+ complexes are in a distorted-tetragonal symmetry field. The d-d electronic transition spectra showed that for Cu(ClO4)(2) complex, the peak of absorption did not change for any degree of metal loading and for Cl- and Br- complexes, the peak maxima shifted to higher energy with lower metal loading. The CoX2(X = Cl-, Br-, ClO4-) analogues possess a distorted-tetrahedral field.

The early systemic and gastrointestinal oxygenation effects of hemorrhagic shock resuscitation with hypertonic saline and hypertonic saline 6% dextran-70: A comparative study in dogs

The smaller volemic state from hypertonic (7.5%) saline (HS) solution administration in hemorrhagic shock can determine lesser systemic oxygen delivery and tissue oxygenation than conventional plasma expanders. In a model of hemorrhagic shock in dogs, we studied the systemic and gastrointestinal oxygenation effects of HS and hyperoncotic (6%) dextran-70 in combination with HS (HSD) solutions in comparison with lactated Ringer's (LR) and (6%) hydroxyethyl starch (HES) solutions. Forty-eight mongrel dogs were anesthetized, mechanically ventilated, and subjected to splenectomy. A gastric air tonometer was placed. in the stomach for intramucosal gastric CO2 (Pgco(2)) determination and for the calculation of intramucosal. pH (pHi):[pHi = pHa - log(Pgco(2)/Paco(2))].The dogs were hemorrhaged (42% of blood volume) to hold mean arterial blood pressure at 40-50 mm Hg over 30 min and were then resuscitated with LR (n = 12) in a 3:1 relation to removed blood volume; HS (n = 12), 6 mL / kg; HSD (n = 12), 6 mL / kg; and HES (mean molecular weight, 200 kDa; degree of substitution, 0.5) (n = 12) in a 1:1 relation to the removed blood volume. Hemodynamic, systemic, and gastric oxygenation variables were measured at baseline, after 30 min of hemorrhage, and 5, 60, and 120 min after intravascular fluid resuscitation. After fluid resuscitation, HS showed significantly lower arterial pH and mixed venous Po-2 and higher systemic oxygen uptake index and systemic oxygenation extraction than LR and HES (P < 0.05), whereas HSD showed significantly lower arterial pH than LR and HES (P < 0.05). Only HS and HSD did not return arterial pH and pHi to control levels (P < 0.05). In conclusion, all solutions improved systemic and gastrointestinal oxygenation after hemorrhagic shock in dogs. However, the HS solution showed the worst response in comparison to LR and HES solutions in relation to systemic oxygenation, whereas HSD showed intermediate values. HS and HSD solutions did not return regional oxygenation to control values.

Relationship of upper-limb and thoracic muscle strength to 6-min walk distance in COPD patients

Study objectives: This study was developed to investigate the influence of thoracic and upperlimb muscle function on 6-min walk distance (6MWD) in patients with COPD.Design: A prospective, cross-sectional study.Setting: the pulmonary rehabilitation center of a university hospital.Patients: Thirty-eight patients with mild to very severe COPD were evaluated.Measurements and results: Pulmonary function and baseline dyspnea index (BDI) were assessed, handgrip strength, maximal inspiratory pressure (Pimax), and 6MWD were measured, and the one-repetition maximum (1RM) was determined for each of four exercises (bench press, lat pull down, leg extension, and leg press) performed on gymnasium equipment. Quality of life was assessed using the St. George Respiratory Questionnaire (SGRQ). We found statistically significant positive correlations between 6MWD and body weight (r = 0.32; p < 0.05), BDI (r = 0.50; p < 0.01), FEV, (r = 0.33; p < 0.05), PImax (r = 0.53; p < 0.01), and all values of 1RM. A statistically significant negative correlation was observed between 6MWD and dyspnea at the end of the 6-min walk test (r = -0.29; p < 0.05), as well as between 6MWD and the SGRQ activity domain (r = -0.45; p < 0.01) and impact domain (r = -0.34; p < 0.05) and total score (r = -0.40; p < 0.01). Multiple regression analysis selected body weight, BDI, Pimax, and lat pull down IRM as predictive factors for 6MWD (R-2 = 0.589).Conclusions: the results of this study showed the importance of the skeletal musculature of the thorax and upper limbs in submaximal exercise tolerance and could open new perspectives for training programs designed to improve functional activity in COPD patients.