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O manejo sustentável dos recursos hídricos e da terra é atualmente uma das principais prioridades na agenda de muitos países ao redor do mundo, o que exige informações sobre as mudanças na cobertura da terra em bacias hidrográficas. Neste estudo, mapas de 1984, 1996, 2005 e 2016 foram desenvolvidos utilizando-se composições falsa-cor e o Índice de Vegetação por Diferença Normalizada (NDVI) para identificar as principais mudanças ocorridas na bacia do Córrego Guariroba. Essa bacia hidrográfica é uma Área de Proteção Ambiental desde 1995, quando se tornou a fonte de abastecimento urbana da capital do estado de Mato Grosso do Sul, Brasil. Para tanto, o software livre QGIS e imagens Landsat foram usados para determinar as mudanças no uso e ocupação da terra. Essas informações permitiram a discussão das possíveis pressões e consequências ambientais das mudanças nesses períodos. A bacia hidrográfica tem estado sob intensa atividade agropecuária, com a maior parte de sua superfície sendo ocupada por pastagens para a pecuária e silvicultura de eucalipto. Os resultados indicam que a influência direta das atividades humanas reduziu drasticamente a cobertura natural na área, com implicações para o cumprimento da legislação do Código Florestal. Os usos antrópicos da terra representam mais de 57% da cobertura total do solo em todos os anos, atingindo 79,70% em 2005. Em 2016, houve um aumento na recuperação da vegetação nativa, mas apesar desse incremento o uso humano da terra continua alto (74,09%). Parte do pequeno ganho de vegetação nativa deve-se aos planos de reflorestamento realizados a partir de 2010. A sedimentação do reservatório de água é visível em 2016, formando bancos de areia que se estendem por cerca de 700 m na porção distal do Córrego Guariroba. Os resultados deste estudo podem ser aplicados para uma possível revisão do plano de manejo da bacia, considerando-se a gestão de seus recursos hídricos integrados ao planejamento ambiental e ao desenvolvimento econômico. Esse tipo de análise pode auxiliar no processo de tomada de decisão de órgãos governamentais, de forma que as bacias utilizadas para o abastecimento de água apresentem restrições de uso da terra, devido ao risco de redução na quantidade e a qualidade da água

This paper reports on the social, cultural, and demographic factors affecting Kuwaiti commuters. The objectives were to 1) investigate the awareness of Kuwaitis of transportation problems, 2) examine the perceptions of Kuwaitis of daily traffic congestion and how it affects them emotionally and physically, and the main objective 3) study the attitudes of Kuwaitis towards using public buses. An online survey was used to examine these factors, and a sample of five hundred transportation system users was obtained. The primary findings showed significant associations between the use of public transport buses and the user’s nationality, gender, age, education, and income level. Men are 2.6 times more likely to use buses, and non-Kuwaiti residents are 6.4 times more likely to use them. In relation to the perceptions of daily traffic congestion, findings indicate that with increase in travel time, commuters, in general, developed more negative feelings, such as exhaustion and stress. A large proportion of the sample population is aware of current local transportation problems and future transportation projects. The results of this study fill a gap in the knowledge of the socioeconomic and cultural factors that influence the success of sustainable public transportation solutions to the traffic challenges found in Kuwait. This knowledge is also crucial to foreign consultants working on planning and transportation projects in the region. It is recommended that officials use this new knowledge on cultural factors to develop integrated land use and transportation plans of the urban areas in Kuwait and to develop more effective and sustainable transportation demand management policies in support of UN Sustainable Development Goals that Kuwait has signed up to pursue.

Remote sensing technology has been applied to monitor anthropogenic changes in the landscape that produce impacts on natural resources, such as environmental degradation, changes in the hydrological cycle and in ecosystems structure and functioning. As digital change detection may be a difficult task to perform, this study proposes a simple and logical technique to display land cover changes using Landsat imagery. Open source geoprocessing tools were used to acquire information for mapping changes on the land surface. The Normalized Difference Vegetation Index (NDVI) and Normalized Difference Water Index (NDWI) derived from satellite images of four dates between 1984 and 2016 were used in RGB composites. The method was used to map gains and losses of vegetation cover and liquid water content in a spatiotemporal scale. The results indicate that this change detection method can effectively reflect the variations occurred over the years. Although both indices have similar responses, NDWI may provide opposite information to NDVI in certain areas, such as in wetlands and riparian zones, presenting wetness losses even in places that exhibit gains in vegetation. This method has applicability to other regions for deriving historical changes.

The paired watershed approach is the most popular tool for quantifying the effects of forest watershed management on water sustainability. But this approach does not often address the critical factor of water stored in the landscape. Future work needs to quantify storage in paired watershed studies to inform sustainable water management.

While alpha rhythm asymmetry among normals is thoroughly documented, the significance of this finding in patients is not well known. The occurrences of alpha amplitude asymmetry in 82 clinical referrals of neuropsychiatric patients was studied in this research. Two separate means of quantifying the alpha asymmetry were used: The first by visual inspection; and the second by measurement in a standard manner. A handedness questionaire was administered and indicated that 77 of the sample were right- and five were left-handed patients. By measurement, the mean overall differences in the alpha amplitude between the hemisphere was small (4 per cent) and non-significant. Seventeen patients showed a difference of 15 per cent or greater, and in two the difference reached 33 per cent. It was concluded that alpha asymmetry must be interpreted with care because it was found that there was an association between left-temporal abnormalities and ipsilateral alpha enhancement, and the greater degrees of asymmetry were found in normal EEGs.

Background and purpose: A prostamide analogue, bimatoprost, has been shown to be effective in reducing intraocular pressure, but its precise mechanism of action remains unclear. Hence, to elucidate the molecular mechanisms of this effect of bimatoprost, we focused on pharmacologically characterizing prostaglandin FP receptor (FP) and FP receptor variant (altFP) complexes. Experimental approach: FP receptor mRNA variants were identified by reverse transcription-polymerase chain reaction. The FP-altFP4 heterodimers were established in HEK293/EBNA cells co-expressing FP and altFP4 receptor variants. A fluorometric imaging plate reader was used to study Ca2+ mobilization. Upregulation of cysteine-rich angiogenic protein 61 (Cyr61) mRNA was measured by Northern blot analysis, and phosphorylation of myosin light chain (MLC) by western analysis. Key results: Six splicing variants of FP receptor mRNA were identified in human ocular tissues. Immunoprecipitation confirmed that the FP receptor is dimerized with altFP4 receptors in HEK293/EBNA cells co-expressing FP and altFP4 receptors. In the studies of the kinetic profile for Ca2+ mobilization, prostaglandin F2α (PGF2α) elicited a rapid increase in intracellular Ca2+ followed by a steady state phase. In contrast, bimatoprost elicited an immediate increase in intracellular Ca2+ followed by a second phase. The prostamide antagonist, AGN211335, selectively and dose-dependently inhibited the bimatoprost-initiated second phase of Ca2+ mobilization, Cyr61 mRNA upregulation and MLC phosphorylation, but did not block the action of PGF2α. Conclusion and implications: Bimatoprost lacks effects on the FP receptor but may interact with the FP-altFP receptor heterodimer to induce alterations in second messenger signalling. Hence, FP-altFP complexes may represent the underlying basis of bimatoprost pharmacology.

Research results on the effects of land cover change on water resources vary greatly and the topic remains controversial. Here we use published data worldwide to examine the validity of Fuh's equation, which relates annual water yield (R) to a wetness index (precipitation/potential evapotranspiration; P/PET) and watershed characteristics (m). We identify two critical values at P/PET=1 and m=2. m plays a more important role than P/PET when m 2. When P/PET 1, suggesting that any land cover changes in non-humid regions (P/PET

Carex bigelowii–Racomitrium lanuginosum moss heath has high conservation value in Britain, being one of the most extensive near-natural habitats and also the preferred habitat of dotterel (Eudromias morinellus). This rare and attractive bird has declined in Britain in the past century, and loss of Racomitrium heath due to heavy sheep grazing and/or nitrogen deposition is probably responsible. Erection of snow fencing for a ski corridor across Carex–Racomitrium heath on Glas Maol, a mountain rising to 1068 m in the eastern Highlands, affected sheep (Ovis aries) usage, and so gave an opportunity to compare trends in botanical composition under different grazing intensities. We began monitoring in 1990, four years after the fence’s erection, and report trends up to 2002/03. Adjacent to the fencing (0–10 m away) sheep usage was much increased due to improved shelter, and C. bigelowii and R. lanuginosum declined, the latter sharply. Racomitrium cover was already reduced by a third in 1990, and fell by a further third over the next 12 years. Grass cover increased to nearly equal Carex cover 16 years after the fence erection. Dicranum fuscescens also spread but lichens declined. There was longer snow-lie near the fence, this being correlated with sheep usage despite somewhat different incidence, and logistic regression showed that for the 1990–1996/97 period Racomitrium loss was rather more closely related to snow-lie than to sheep pellet-group density, whereas Agrostis increase was highly significantly related to pellet-group density. Distant to the fence the composition of the Carex–Racomitrium heath changed little over 12 years of monitoring. Agrostis increased and C. bigelowii declined, both changes being significant but much smaller than adjacent to the fence. Also Polytrichum alpinum increased significantly and some lichens declined. For Racomitrium there was a fall of only 2.5% from its initial cover of 40% in 1990. Since the dung counts showed only a negligible reduction in sheep usage between plots at 13–15 and 43–45 m from the fence, the trends in composition recorded at positions 19–20 and 39–40 m from the fence apply to the extensive moss heath used by the dotterel on Glas Maol. These birds still nest in the distant zone, and we judge that the condition of the Carex–Racomitrium heath will remain satisfactory for them unless sheep usage increases by 25% or more. However, the ongoing loss of lichens and the sparsity of Vaccinium myrtillus imply that the current level of sheep grazing has appreciably modified this community from its former pristine condition.

This study used a paired-catchment approach to investigate the effects of harvesting on streamflow for Camp Creek, a snowmelt-dominated stream in the southern interior of British Columbia. The drainage area for Camp Creek is 33.9 km2, and 27 percent of the area was harvested in response to a pine beetle infestation. Adjacent Greata Creek, with a drainage area of 40.7 km2, served as a control. Harvesting resulted in a significant increase in April flows, which persisted with no evidence of recovery through the 18-year post-treatment period, as well as a significant advance in the timing of peak flows relative to those for the control stream. No significant nor apparent changes in seven-day low flows were detected. Peak flows appeared to increase for smaller events, but not for larger events, although this result was not statistically significant. Detection of significant harvesting effects on low flows, peak flows and annual water yield may have been hampered by inherent differences between the two catchme...

Objectives: To determine if certain loggers are at increased risk of death during logging operations. Methods: Statistical analysis of 780 logger fatalities for a nine year period (1992–2000). Results: The major findings are: (1) treefallers suffer nearly 63% of all fatalities, (2) the region where the fatality occurred and the size of the employer were not significant factors that contributed to a high percentage of treefaller fatalities, and (3) the Northeast and Midwest regions showed a higher percentage of fatalities compared with the South and West regions. Conclusions: Overall, the logger fatality rate for 1992–2000, compared with 1980–88 has decreased slightly; however, treefallers continue to be the group of loggers who suffer the highest fatality rate.

The aim was to investigate the impacts of trampling on water loss and partitioning in vegetation with contrasting structure and species composition. A new design of weighing lysimeter was used in glasshouse experiments to compare evapotranspiration from intact and trampled blocks of vegetation. The lysimeter system was able to detect differences between treatments after only a few hours. Evapotranspiration was recorded for six communities, representative of cryptogam - vascular plant communities found in the Cairngorm Mountains of Scotland. Vegetation blocks of Racomitrium and Vaccinium/Hylocomium heath communities had the greatest cumulative evapotranspiration and lichen heath the least over 48 h. Blocks from three of the communities (Agrostis/Festuca grassland, Calluna wet heath, and lichen heath) were used in a trampling experiment with five levels of damage. Trampling progressively destroyed the structure of the vegetation of all communities and increased the rates of water loss from the blocks. The grassland community vegetation was the most resilient. These results help to link the massive changes in vegetation structure resulting from trampling to effects on water loss and microclimate.Key words: weighing lysimeter, evapotranspiration, recreation, trampling, cryptogams, montane vegetation.

In the last decade, environmental management has emerged as an exciting and relevant sub-discipline of geography in South Africa in line with global trends. The paper examines the relationship between geography and environmental management in South Africa; the role that geographer's are playing in this discipline; and the future of this relationship. The paper identifies eleven themes in the environmental management literature in South Africa and suggests that geography plays a crucial role in providing the theoretical foundation for the more applied paradigm of environmental management. It is proposed that South African geographers need to develop new approaches that challenge the status quo and lead to social, environmental and ecological justice.

The occurrence of Scots pine (Pinus sylvestris L.) seedlings and saplings (

The reductions in streamflow associated with timber plantations are of particular concern in South Africa and, as a means of sustaining flows, permits granted by the state for the establishment of plantations have required that plantings should be no closer than 20-50 m from streams and other waterbodies. This paper presents the results of three catchment experiments, analysed by the paired catchment method, that aimed to provide a quantitative evaluation of the water yield savings attributable to this practice. These experiments show conclusively that, for South African conditions, riparian vegetation is a more liberal user of water than vegetation in other parts of a catchment and that the clearing of indigenous forest or exotic trees in the riparian zone of the catchment will result in disproportionately greater gains in water yield than would result from clearing similar vegetation elsewhere in the catchment. First year flow increases from clearing of tall woody vegetation in the riparian zone ranged from 55 to 110 mm (9-44%) per 10% of catchment cleared. In the same catchments, clearing of similar vegetation in upslope (nonriparian positions) led to flow increases ranging from 27 to 35 mm (2.5-14%) per 10% of catchment cleared.

The changes in streamflow following the removal of invasive wattle (Acacia mearnsii and A. longifolia) from riparian zones during the dry summer months in three small catchments in the Western Cape Province are described. Portable steel box weirs, with a 30° compound V-notch and equipped with Belfort water level recorders, were used to measure streamflow. Each of the three streams had a control catchment against which it was correlated during a pre-treatment period. The riparian zones of the treatment catchments were cleared after this period of calibration, and the response of stream-flow after treatment was recorded. In the three catchments there was a marked increase in streamflow after clearing of the riparian invasive vegetation. The streamflow increases in the three catchments were 8,8, 10,4 and 12 m3/day per ha cleared. The responses measured in these experiments are the result of changing from tall vegetation to minimal cover and represent a maximum response. Streamflow is expected to decrease aga...

The mountains of the Western Cape Province fulfil a vital water supply function in the region. For the protection of this water supply, it is important to understand natural soil erosion rates in t...

The reductions in streamiIow following the afforestation of grassland with Eucalyptus grands and Pinus pun& in the Mokobulaan research catchments on the Mpumalanga escarpment, and the subsequent response in streamflow to cleat-felling of the eucalypts are presented. Afforestation with eucalypts of an entire catchment with a virgin annual runoff of 236 mm, caused a statistically significant decrease in streamflow in the third year after planting and the stream dried up completely in the ninth year after planting. The eucalypts were clearfelled when 16 years old but full perennial streamflow did not return until five years later. Afforestation with pines of an entire catchment with a virgin annual runoff of 217 mm, produced a significant decrease in streamflow in the fourth year after planting and caused the stream to dry up completely in the twelfth year after planting. The drying up of the streams was not altogether surprising as the annual runoff was lower than the expected reductions owing to complete afforestation. The delayed return of streamflow in the clearfelled catchment is surprising though, and is attributed to the desiccation of deep, soil-water stores by the eucalypts. These stores had to be replenished before the streams could return to normal behaviour. Q 1997 Elsevier Science B.V.

The paired catchment method was used to test for the effects of thinning on the water yield in three afforested catchments in South Africa, namely, Biesievlei, Jonkershoek, 98% afforested with Pinus radiata (three thinnings); Westfalia catchment D, 100% afforested with Eucalyptus grandis (two thinnings); and Cathedral Peak CII that was 74% afforested with Pinus patula (one thinning). During and after two separate thinnings, each of which removed roughly one third of the stems in a maturing P. radiata plantation in the Biesievlei catchment, annual streamflow increased by between 10 and 71% (19–99 mm). These increases persisted for three and two years after the thinning, respectively. A final thinning in the same catchment removed only 22% of stems at an age of 28 yr. The following years (1977 and 1978) were wetter than average, and reductions in annual streamflow of 26 and 55% were recorded in these two years. At Westfalia catchment D and Cathedral Peak CII, the hydrological trends were entirely dominated by the rapidly declining streamflow caused by the developing E. grandis and P. patula plantations respectively. Any savings in water use that may have resulted from the thinning of these plantations were insufficient to affect the downward trend in annual streamflow. Thinnings may have had a minor effect of delaying or reducing the desiccation of these catchments but such effects could not be assessed due to natural variability and the limited resolution of the paired catchment method. The trends in total water yield from the catchments were generally mirrored in the dry season streamflow, and there were no strong indications that thinning effects are linked to a particular season.

In an effort aimed at locating highly stressed and destressed areas that may influence rockbursts, the US Bureau of Mines conducted an active 3-D seismic tomographic investigation between the 7100 and 7250 levels (2165 m to 2210 m depth) of the Homestake gold mine, Lead, South Dakota. Existing rock bolts were used to mount geophones and as strike points for introducing seismic energy (nominally 750 Hz) using an 8-lb sledge hammer. Approximately 2900 compressional wave travel time measurements were recorded spanning up to 155 m between drifts at several levels. Eight different reconstructions, computed using different uniform starting models, were averaged together to produce a robust final velocity model. The average velocity tomogram portrayed a heterogeneous structure (3–6.8 km/s). Regions of low-velocity correlated with known locations of drifts, stopes, ore shoots, and rockburst damage, while high-velocity regions were indicative of elevated levels of compressional stress. 3-D isoprobability surfaces were used to assess the degree of risk associated with anomalous regions; significant risk zones appeared adjacent to backfilled slopes and at the center of pillars indicating the likelihood of concentrated stress.

SYNOPSIS Some areas of forestry estates, including unplantable ones, may be zoned and managed for nature conservation. This paper is an analysis of the results of studies of plants, birds and small mammals at Jonkershoek, Stellenbosch, to determine whether pine plantations are “inhospitable” to ecological and demographic processes required for the persistence of these biota in native habitat “islands” within forestry areas. The present study indicates that pine plantations are not unqualified “inhospitable seas”. However, the human-assisted dominance of the pines over the indigenous vegetation eliminates many species of the original habitat and reduces the numbers, or the frequency of occurrence, of the remaining species. There were significantly fewer vertebrate-pollinated, indigenous, plant species in the plantation sample than in the mountain fynbos one, and significantly more vertebrate-dispersed, native, plant species. Vertebrate pollinators were infrequently recorded in, or absent from, mature pine ...

SYNOPSIS The paired catchment method was used to measure the effects of riparian zone clearing and clearfelling on streamflow, stormflows and water quality. The forested riparian zone of a 39,6 ha, humid Northern Province catchment, amounting to 10 % of the catchment area, was cleared and kept clear of vegetation. Two years later the entire catchment was cleared by bulldozing and burning its cover of indigenous evergreen forest and scrub forest, and replanted to Eucalyptus grandis seedlings. The riparian clearing resulted in a small 55 mm (9 %) increase in streamflow in the first year, and mean increases per storm in quickflow volume of 2,32 mm (71 %), in stormflow volume of 4,60 mm (76 %) and in storm response ratio by 2,37 % (a 50 % increase). By the second year these effects were diminished, and total flow was reduced by 56 mm (19 %) below expected flow. Clearfelling and replanting of the catchment had similarly small effects on streamflow and stormflows. This could be ascribed partly to a serious drou...

Mining-induced stress-field changes pose both safety and economic hazards. In an effort aimed at developing technology for mitigating such hazards, the Bureau of Mines together with Hecla Mining Company conducted an active 3-D seismic tomographic investigation of anomalous rockmass conditions in a large underground, high-grade, remnant ore pillar, at the Lucky Friday mine near Mullan, ID. Roughly 2400 P-wave traveltime measurements, were simultaneously inverted to obtain a velocity distribution. The resulting velocity structure appears extremely heterogeneous (1.5–6.0 km/s) and well correlated with mechanical models indicating the transfer of stress in direct response to mining. Regions of anomalous ground (intense fracturing or high-stress) were identified using threshold probabilities; the minimum velocity regions surrounding drifts indicate a zone of stress relief that extends up to three drift diameters into the rockmass, while regions of maximum velocity above and below mined-out portions of veins indicate the likelihood of concentrated stress. Active tomographic imaging provides the engineer with a flexible tool for routine underground 3-D monitoring of mechanical conditions in large mine structures.

Streamflow and its storm-flow elements in four catchments were analyzed by the paired catchment method for a response to fire. Prior to burning two of the catchments were vegetated with over-mature fynbos (the indigenous scrub vegetation of the southwestern Cape, South Africa), one was afforested with Pinus radiata and the fourth with Eucalyptus fastigata. One of the fynbos catchments was burned in a prescribed fire in the late dry season. The other catchments burned in wildfires. Neither of the fynbos catchments showed a change in storm-flow. Annual total flow increases of around 16% were in agreement with model predictions, being related to the reductions in transpiration and interception. The manner of streamflow generation appeared to have remained unaltered despite the presence of some water repellency in the soils and consequent overland flow on some steep midslope sites. The two timber plantation catchments experienced large and significant increases in storm-flows and soil losses, while total flow increased by 12% in the pine catchment and decreased marginally in the eucalypt catchment. The pattern of the storm-flow increases was similar in both cases. After fire, storm hydrographs were higher and steeper though their duration was little changed. The respective first year increases in the pine and eucalypt catchments were 290% and 1110% for peak discharge, 201% and 92% for quick-flow volume, and 242% and 319% for storm response ratio. These fire effects are considered to be due to changes in storm-flow generation consistent with an increased delivery of overland flow (surface runoff) to the stream channel. This was caused, in part, by reduced infiltration resulting from water repellency in the soils of the burned catchments. Overall the hydrological effects of fire are related to numerous interactive factors, including the degree of soil heating, the vegetation type and soil properties.

[1] Changes in vegetation cover can significantly affect streamflow. Two common methods for estimating vegetation effects on streamflow are the paired catchment method and the time trend analysis technique. In this study, the performance of these methods is evaluated using data from paired catchments in Australia, New Zealand, and South Africa. Results show that these methods generally yield consistent estimates of the vegetation effect, and most of the observed streamflow changes are attributable to vegetation change. These estimates are realistic and are supported by the vegetation history. The accuracy of the estimates, however, largely depends on the length of calibration periods or pretreatment periods. For catchments with short or no pretreatment periods, we find that statistically identified prechange periods can be used as calibration periods. Because streamflow also responds to climate variability, in assessing streamflow changes it is necessary to consider the effect of climate in addition to the effect of vegetation. Here, the climate effect on streamflow was estimated using a sensitivity-based method that calculates changes in rainfall and potential evaporation. A unifying conceptual framework, based on the assumption that climate and vegetation are the only drivers for streamflow changes, enables comparison of all three methods. It is shown that these methods provide consistent estimates of vegetation and climate effects on streamflow for the catchments considered. An advantage of the time trend analysis and sensitivity-based methods is that they are applicable to nonpaired catchments, making them potentially useful in large catchments undergoing vegetation change.

First-motion analyses of digital seismic records and an assessment of damage provided conclusive evidence that a fault-slip source mechanism was responsible for a Richter magnitude 2 that occurred at the Lucky Friday Mine on April 13, 1990. This event was the first time that movement along an argillite bed had been observed after the macroseismic monitoring system had been installed. The physical evidence of a shear-slip type failure established confidence in using double-couple, first-motion analyses for the macroseismic system. The U.S. Bureau of Mines is conducting this research as part of its mission to enhance safety by reducing rockburst hazards in mines.

[1] The longer-term effects of afforestation with Pinus radiata and Eucalyptus grandis on streamflows were analyzed using data from two paired-catchment experiments in South Africa. The experiments are rare in that they have been maintained over longer periods than the typical rotation period for industrial timber plantations in the tropics or subtropics. In both experiments the planting treatments led to large reductions in streamflow, which increased with the age of the trees and were positively related to water availability. The pine plantation caused peak reductions in yield over a 5-year period of 44 mm a−1 or 7.7% a−1 for each 10% of catchment planted when the trees were between 10 and 20 years old. The eucalypt plantation caused peak reductions over a 3-year period of 48 mm a−1 and 10% a−1 for each 10% of catchment planted. However, as the plantations matured (over 30 years of age in the case of pines and over 15 years of age in the case of eucalypts) the flow reduction trend was reversed, and streamflow effects appear to be tending toward preafforestation levels. The longer-term effects of planted forests need not be as harmful on the water yield of catchments as has been predicted from shorter-term studies. The implication of these results is that if trees are grown on very long rotations, they may be used for restoring degraded catchments or as a means of storing carbon without completely denuding available water resources.

Background and purpose: A prostamide analogue, bimatoprost, has been shown to be effective in reducing intraocular pressure, but its precise mechanism of action remains unclear. Hence, to elucidate the molecular mechanisms of this effect of bimatoprost, we focused on pharmacologically characterizing prostaglandin FP receptor (FP) and FP receptor variant (altFP) complexes. Experimental approach: FP receptor mRNA variants were identified by reverse transcription-polymerase chain reaction. The FP-altFP4 heterodimers were established in HEK293/EBNA cells co-expressing FP and altFP4 receptor variants. A fluorometric imaging plate reader was used to study Ca2+ mobilization. Upregulation of cysteine-rich angiogenic protein 61 (Cyr61) mRNA was measured by Northern blot analysis, and phosphorylation of myosin light chain (MLC) by western analysis. Key results: Six splicing variants of FP receptor mRNA were identified in human ocular tissues. Immunoprecipitation confirmed that the FP receptor is dimerized with altFP4 receptors in HEK293/EBNA cells co-expressing FP and altFP4 receptors. In the studies of the kinetic profile for Ca2+ mobilization, prostaglandin F2α (PGF2α) elicited a rapid increase in intracellular Ca2+ followed by a steady state phase. In contrast, bimatoprost elicited an immediate increase in intracellular Ca2+ followed by a second phase. The prostamide antagonist, AGN211335, selectively and dose-dependently inhibited the bimatoprost-initiated second phase of Ca2+ mobilization, Cyr61 mRNA upregulation and MLC phosphorylation, but did not block the action of PGF2α. Conclusion and implications: Bimatoprost lacks effects on the FP receptor but may interact with the FP-altFP receptor heterodimer to induce alterations in second messenger signalling. Hence, FP-altFP complexes may represent the underlying basis of bimatoprost pharmacology.

A wildfire in February 1986 destroyed most of an afforested research catchment in the southwestern Cape region of South Africa. The hydrological consequences of the fire were quantified using monitored pre-fire and post-fire stream flow and sediment data from the burned catchment and a nearby control catchment. Soil loss and soil wettability were also measured. In the first year after the fire, weekly stream flow totals increased by 12%, quick flow volumes increased by 201%, peak flow rates increased by 290% and catchment response ratio increased by 242%. Soil loss on overland flow plots ranged from 10 to 26 t ha−1, and suspended sediment and bedload yields each increased roughly four-fold following the fire. Wettability of the soils was greatly reduced by the passage of fire. Surface soil layers (0–10 mm) were burned clean of any inherent water repellency by the passage of a hot fire, but more severe repellency, in broader bands, was induced in deeper soil levels by the heating of the soil. It is postulated that the widespread development of water repellency in the soil led to overland flow during larger rainstorms, which in turn caused the markedly altered hydrological behaviour of the catchment and the high soil losses relative to the unburned condition.

The outcome of 38 children with endstage renal failure who entered a dialysis and renal transplant programme over a period of 16 years is reported. The initial care was given in an adult programme but in 1985 this was changed to a comprehensive and specifically paediatric programme. Patient survival was 97, 86 and 80% at 1, 5 and 10 years respectively. Thirty-four of the patients spent a mean period of 19 months (range 1-160 months) on dialysis with the preferred form of dialytic therapy being continuous ambulatory peritoneal dialysis. Primary cadaveric graft survival was 72 and 42% at 1 and 3 years respectively; although since 1985 1 year graft survival has risen to 90%. The major long term problems have been growth failure and poor social development. Eighty-seven per cent of children have been able to continue normal schooling, and of the 18 who have left school 14 (78%) are employed or undertaking tertiary education. Thus dialysis and transplantation has allowed not only excellent patient survival but also the achievement of satisfactory educational standards and subsequent employment for the majority of patients.

Preservation of rat kidneys by simple ice-storage has been demonstrated after 48 hr using the University of Wisconsin (UW) solution; hypothermic preservation of the rat kidney was dramatically improved. A modified UW solution without hydroxyethyl starch (HES) also gave uniform survival after 48 hr of storage, and even better function and morphology. Substitution of HES from another source also improved renal function when compared with UW (Dupont) and it is suggested that prolonged storage of UW solution prior to use may reduce its effectiveness. Reversing the Na:K ratio of the solution still allowed successful preservation, but significantly worsened morphology of the surviving kidney.

We surveyed 70 epileptic patients attending a general neurology clinic and 64 patients attending an epilepsy clinic to determine the incidence of alcohol-related seizures. Seven (10%) of the neurology clinic patients and 9 (15%) of the epilepsy clinic patients reported exacerbation of their seizures with alcohol. In the first group, two had been heavy drinkers when under-age, two had features of alcohol dependence, and three had experienced resolution of seizures following cessation of their drinking. In the second group, five drank 4 units/day or more, and one drank more heavily. The importance of alcohol in the causation of these patients’ seizures had not previously been appreciated. The relationship of alcoholism to epilepsy has been recognized for many years, but the role of alcohol in the exacerbation of primary epilepsy, and in triggering seizures in epileptic patients is often not recognized. Control of alcohol ingestion is an important factor in the management of epilepsy.

An increasing awareness of the occurrence and implications of soil water repellence has caused a surge in research activity addressing this phenomenon in recent years. This has involved not only the disciplines of hydrology, soil, and related environmental sciences, but increasingly also biology, chemistry, physics, and surface sciences, which has allowed elucidation of the causes and behaviour of soil water repellence based on first order principles. Furthermore, novel approaches and advances in technology have allowed examination of its causes and implications at increasingly coarse and fine spatial and temporal scales. The 19 papers presented in this special issue exemplify this trend by bringing together studies from diverse disciplines and presenting the latest advances regarding the origin, occurrence, controls, hydrological effects, and amelioration of soil water repellence. Here we aim to summarize, evaluate and set into context some of the new insights arising from these studies and also attempt to identify the key current and likely future research gaps related to water repellence in soils

The aim of this systematic review was to compare the safety and efficacy of laparoscopic live donor nephrectomy with the "gold" standard of open live donor nephrectomy.Three search strategies were devised to enable literature retrieval from the Medline, Current Contents, Embase, and Cochrane Library databases up until, and including, February 2000.Inclusion of a report was determined on the basis of a predetermined protocol, independent assessment by two reviewers, and a final consensus decision. English language reports were selected and acceptable study designs included randomized-controlled trials, controlled clinical trials, case series, or case reports. Each report was required to provide information on at least one of several safety and efficacy outcomes as detailed in the protocol.Twenty-five reports met the inclusion criteria. They were tabulated and critically appraised in terms of the methodology and design, sample size, outcomes, and the possible influence of bias, confounding, and chance.High level evidence comparing the safety and efficacy of laparoscopic live donor nephrectomy with open donor nephrectomy was not available at the time of this review. Limited low level evidence suggested that the laparoscopic approach might be advantageous regarding the donor's hospital stay, convalescence, pain, and resumption of employment.The ASERNIP-S Review Group concluded that the evidence-base for laparoscopic live donor nephrectomy was inadequate to make a safety and efficacy recommendation. Clinical and research recommendations were developed regarding the introduction and current practice of this procedure in Australia.

Beta(s)-chromosome haplotypes are peculiar to specific regions of Africa and Asia and are associated with the occurrence of different fetal hemoglobin (Hb) levels in sickle cell patients. Among these haplotypes, beta(s)-chromosomes found in the Senegal and the Arab-India regions are associated with relatively high levels of HbF expression, whereas those around the Benin, Bantu, and the Cameroon regions show low levels of HbF expression. The roles of 5'HS2 and the 5' flanking (promoter region) region in the expression of globin genes are well documented. Haplotype specific variations are found in these regions and have been postulated to be involved in the regulation of HbF expression. In this study, we have analyzed the effect of sequence variations in regulatory regions of the Bantu 5'HS2 and 5' flanking region of the Ggamma gene on CAT expression. A diminution was observed in K562 cells when the promoter originated from the Bantu beta(s) chromosome. The decreased expression was independent of the origin of the 5'HS2 sequence--combinations of the Bantu promoter were measured with the Benin, Bantu, or Senegal 5'HS2 sequences in K562 cells. However, expression of the same plasmids in murine erythroleukemic (MEL) cells showed no difference in CAT expression among the various sequence combinations studied.

Uncemented porous-coated cobalt-chrome femoral stems have produced satisfactory short-term clinical results, although slightly inferior to the results of cemented total hip arthroplasty. Proximal femoral bone resorption, osteolysis and fibrous ingrowth have been reported with porous-coated stems. Hydroxyapatite-coated stems and titanium stems have been introduced to avoid these findings through improved fixation. Dual-energy x-ray absorptiometry allows quantitative examination of bone density changes after uncemented total hip arthroplasty. This study examines the host-bone response to hydroxyapatite-coated titanium and porous-coated cobalt-chrome stems of identical geometry in three paired bilateral cases at 5 to 7 years. Distinctly different patterns of femoral bone mineral density changes were observed with the two stem designs. The authors conclude that dual-energy x-ray absorptiometry is a promising technique allowing noninvasive analysis of uncemented stem fixation, and that the data from this study suggest improved fixation and stress transfer with hydroxyapatite-coated titanium stems.

There are five major haplotypes associated with sickle cell anemia (SS). Individuals homozygous for haplotypes 3 (Senegal) and 31 (Saudi Arabian) have high fetal hemoglobin (HbF) levels (15 to 30% of total hemoglobin) whereas individuals homozygous for haplotypes 17 (Cameroon), 19 (Benin), and 20 (Bantu) have low HbF levels (1 to 10%). We previously identified several point mutations in the LCR 5'HS-2 that were specific for haplotype 19 beta s chromosomes (compared to the GenBank HUMHBB reference sequence, T--G at position 8580, A--G at position 8598, and A--T at position 9114). We postulated that one or more of these mutations may alter the binding of specific trans-acting factors and ultimately affect the expression of HbF in these sickle cell patients. We performed gel mobility shift assays using 32P-end-labeled double-stranded 19mers corresponding to each of the LCR 5'HS-2 normal (GenBank) and mutant sequences. Nuclear extracts prepared from HeLa and HEL cells were used in our experiments and neither the normal nor mutant sequence at position 8580 bound trans-acting factors in either nuclear extract. The 8598 mutant increased binding of Sp1; using purified protein and both nuclear extracts. HEL extracts were used to quantify the increase in Sp1 binding to the 8598 mutation and we found an increase in binding of 66 and 47%, respectively, in two shifted bands. The 9114 mutation sharply decreased binding of an unknown trans-acting factor by 74%. This factor was present in both HeLa and HEL nuclear extracts.

A retrospective study was undertaken to determine the intraoperative blood loss and the subsequent need for blood transfusion in primary total knee arthroplasty. Fifty-six patients were operated on with the use of an arterial tourniquet (group 1), and 50 patients, without the use of a tourniquet (group 2). The mean intraoperative blood loss was significantly different between the two groups (P = 0.001). The 1-hour postoperative hemoglobin decrease was also significantly different between the two groups (P = 0.006). Thirty-four patients (61%) in group 1, and 32 patients in group 2 (64%) required a blood transfusion prior to discharge from the hospital. This difference was not significantly different. Although intraoperative blood loss was increased in the group when no tourniquet was used, the overall incidence of transfusion was the same between the two groups. It may therefore be justified to question the routine use of a tourniquet during total knee arthroplasty.

Three-dimensional seismic imaging has a number of important advantages over two-dimensional tomography, in artifact suppression and selfconsistency. However, the underdetermined or illconditioned nature of the inversion is typically more severe in three dimensions than in two. Methods for characterizing resolution and robustness are concomitantly more important for three-dimensional studies. Checkerboard resolution tests and robustness tests based on multiple inversion with different starting models provide means of evaluating the results of travel-time inversions for two underground mine sites.