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Land-use change is the single biggest driver of biodiversity loss in the tropics. Biodiversity models can be useful tools to inform policymakers and conservationists of the likely response of species to anthropogenic pressures, including land-use change. However, such models generalize biodiversity responses across wide areas and many taxa, potentially missing important characteristics of particular sites or clades. Comparisons of biodiversity models with independently collected field data can help us understand the local factors that mediate broad-scale responses. We collected independent bird occurrence and abundance data along two elevational transects in Mount Kilimanjaro, Tanzania and the Taita Hills, Kenya. We estimated the local response to land use and compared our estimates with modelled local responses based on a large database of many different taxa across Africa. To identify the local factors mediating responses to land use, we compared environmental and species assemblage information between sites in the independent and African-wide datasets. Bird species richness and abundance responses to land use in the independent data followed similar trends as suggested by the African-wide biodiversity model, however the land-use classification was too coarse to capture fully the variability introduced by local agricultural management practices. A comparison of assemblage characteristics showed that the sites on Kilimanjaro and the Taita Hills had higher proportions of forest specialists in croplands compared to the Africa-wide average. Local human population density, forest cover and vegetation greenness also differed significantly between the independent and Africa-wide datasets. Biodiversity models including those variables performed better, particularly in croplands, but still could not accurately predict the magnitude of local species responses to most land uses, probably because local features of the land management are still missed. Overall, our study demonstrates that local factors mediate biodiversity responses to land use and cautions against applying biodiversity models to local contexts without prior knowledge of which factors are locally relevant. [ABSTRACT FROM AUTHOR]

Aim We conduct the first assessment of likely future climate change impacts for biodiversity across the West African protected area ( PA) network using climate projections that capture important climate regimes (e.g. West African Monsoon) and mesoscale processes that are often poorly simulated in general circulation models ( GCMs). Location West Africa. Methods We use correlative species distribution models to relate species (amphibians, birds, mammals) distributions to modelled contemporary climates, and projected future distributions across the PA network. Climate data were simulated using a physically based regional climate model to dynamically downscale GCMs. GCMs were selected because they accurately reproduce important regional climate regimes and generate a range of regional climate change responses. We quantify uncertainty arising from projected climate change, modelling methodology and spatial dependency, and assess the spatial and temporal patterns of climate change impacts for biodiversity across the PA network. Results Substantial species turnover across the network is projected for all three taxonomic groups by 2100 (amphibians = 42.5% (median); birds = 35.2%; mammals = 37.9%), although uncertainty is high, particularly for amphibians and mammals, and, importantly, increases across the century. However, consistent patterns of impacts across taxa emerge by early to mid-century, suggesting high impacts across the Lower Guinea forest. Main conclusions Reducing (e.g. using appropriate climate projections) and quantifying uncertainty in climate change impact assessments helps clarify likely impacts. Consistent patterns of high biodiversity impacts emerge in the early and mid-century projections, while end-of-century projections are too uncertain for reliable assessments. We recommend that climate change adaptation should focus on earlier projections, where we have most confidence in species responses, rather than on end-of-century projections that are frequently used. In addition, our work suggests climate impact should consider a broad range of species, as we simulate divergent responses across taxonomic groups. [ABSTRACT FROM AUTHOR]

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In spite of high loss of biodiversity in landscapes converted to farmland or urban areas, a positive correlation exists between species richness and endemism and human population density at coarse spatial scales. Data representing precolonial and contemporary human population patterns in Africa were overlaid on species distribution data covering 4080 vertebrate species. Species richness tracks both the precolonial and the current human population density. Areas of high vertebrate endemism are particularly closely associated with precolonial population centres. This suggests that patterns of population growth in Africa were, more than today, governed by factors that also enhanced local species persistence and speciation. The traditional conservation focus on wilderness areas with few people, and generally rather low endemism, needs to be complemented with strategies for sustainable development in some of the densely populated areas. [ABSTRACT FROM AUTHOR]

The hippocampal formation (HF) plays a key role in novelty detection, but the mechanisms remain unknown. Novelty detection aids the encoding of new information into memory-a process thought to depend on the HF and to be modulated by the theta rhythm of EEG. We examined EEG recorded in the HF of rats foraging for food within a novel environment, as it became familiar over the next five days, and in two more novel environments unexpectedly experienced in trials interspersed with familiar trials over three further days. We found that environmental novelty produces a sharp reduction in the theta frequency of foraging rats, that this reduction is greater for an unexpected environment than for a completely novel one, and that it slowly disappears with increasing familiarity. These results do not reflect changes in running speed and suggest that the septo-hippocampal system signals unexpected environmental change via a reduction in theta frequency. In addition, they provide evidence in support of a cholinergically mediated mechanism for novelty detection, have important implications for our understanding of oscillatory coding within memory and for the interpretation of event-related potentials, and provide indirect support for the oscillatory interference model of grid cell firing in medial entorhinal cortex. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Presents abstracts of articles about urinary calculi, to be discussed at the Annual Scientific Meeting of the British Association of Urological Surgeons from June 23-27, 2003 in Manchester, England. `Can renal protocol CT be interpreted by the urologist?,' by S.S. Connolly et al.; `The management of upper tract urological stone disease,' by S.J. Symons et al.

Abstract. Biogeographical zones are described for terrestrial bird species endemic to the Afrotropics using up-to-date distributional data and multivariate statistical techniques. This provides an objective basis for a hierarchy of subregions, provinces and districts, based on a set of rules. Results are compared to previous studies at continental and regional scales. Biogeographical zones for passerines and non-passerines are compared and found to be similar. Peaks of species richness and narrow endemism are described for the six major subdivisions (subregions) identified by the cluster analysis. Coincidence of peaks of species richness and narrow endemism is found to be low, such that areas selected to represent high species richness tallies will often fail to represent narrow endemics. Strong regionalization of Afrotropical birds indicates the need to use a biogeographical framework in conservation priority setting exercises to ensure that unique, but species-poor, avifaunas are not neglected. [ABSTRACT FROM AUTHOR]

Examines the use of spiral computed tomography for the assessment of acute loin pain of renal colic. Evaluation on the accuracy and sensitivity of the method; Effectiveness of the method in patients with small stones; Ability to detect the presence of calculi.

Surface and leaf litter arthropod assemblages of the seasonal lowland coastal forests of eastern Tanzania were investigated from eleven sites over a 3-year period (1991–93). Pit-fall trap data show that four groups comprise more than 10% of the total sample: ants (Hymenoptera: Formicidae, 31%), grasshoppers and crickets (Orthoptera, 22%), beetles (Coleoptera: 17.39%) and spiders (Araneae: 13.48%). Arthropod abundance varies considerably with season, with greater total numbers of arthropods in all groups found in wetter periods. Arthropod abundance also varies considerably according to habitat, with greatest numbers found in forests with the most intact canopy cover, and in valley-bottom forest as compared to ridge-top forest; the valleys are normally both wetter and with a more complete and taller canopy. Tullgren Funnel data show that over 50% of the leaf litter fauna comprises tiny arthropods of the groups Collembola and Acarina. Abundance of arthropods in the leaf litter of these forests varies from a maximum of ≈ 16,000 m–2 , to a minimum of 780 m –2 . Abundance is highest in wetter periods, in the forest areas with the most intact canopy cover, and in valley-bottom as opposed to ridge-top habitats. [ABSTRACT FROM AUTHOR]

Objective To describe trends in deaths from prostate cancer between 1970 and 1990, and trends in registrations of prostate cancer between 1971 and 1986. Methods Data on prostate cancer deaths and registrations were obtained from the Office of Population Censuses and Surveys, and age specific rates were calculated. Results The number of deaths from prostate cancer rose by 107% between 1970 and 1990, from 3906 to 8098. The number of registrations of prostate cancer rose by 75% between 1971 and 1986, from 5819 to 10 180. Age-specific death rates and registration rates also increased but by a smaller amount than the rise in absolute numbers. Conclusions A component of the increase seen in both the number of prostate cancer deaths and registrations can be explained by a concomitant increase in the elderly male population, the group at highest risk, but the rises seen in rates are more difficult to explain, The rises are likely to have had considerable implications for the workload of urologists and should be taken into account when planning future health services. With further increases expected over the next decade in the elderly male population, deaths and registrations from prostate cancer will continue to rise. Research will be required to determine possible reasons for the increase seen in prostate cancer rates over the last 20 years, to determine the true incidence and prevalence of prostate cancer in the general population and to identify possible aetiological factors. [ABSTRACT FROM AUTHOR]

- A comparative study of transurethral (TUR) and open prostatectomy for the large prostate gland has been carried out. Over a 5-year period 94 transurethral resections and 73 open procedures were performed for prostate glands weighing more than 50 g. There was a single death in each group, giving relative mortality rates of 1.1% TUR and 1.4% open. The post-operative hospital stay was significantly shorter in the TUR group. The open group suffered significantly more complications in the first week but the TUR patients, although having fewer immediate postoperative complications, had significantly more in the first year, so that overall complication rates were similar (35% vs 36%). Patient satisfaction was equal in both groups. [ABSTRACT FROM AUTHOR]

This article presents a case report on management of urethral metastasis from colorectal carcinomas. Urethral tumors are extremely rare. Just over 600 cases have been reported so far.' Squamous cell carcinoma accounts for 70% of the primary tumors. Adenocarcinoma from paraurethral glands accounts for 10-20% of urethral primaries. Melanomas and various sarcomas have also been reported. Secondary tumors of the urethra are even more rare. Metastases from prostatic carcinoma have been reported in men. Metastases from renal cell carcinoma, Wilms' tumor and urachal adenocarcinoma have also been reported. In these two cases of urethral metastases, one from rectal carcinoma and the other from sigmoid carcinoma, their diagnosis and urological management.

Presents a case study of dispensing error of substituting quetiapine for nefazodone for treatment of epilepsy and depression. Clinical history of the patient; Effects of quetiapine; Statistics on dispensing errors in the U.S.

Comments on the adoption of laparoscopic approach to ureteric stones than ureterolithotomy. Emphasis on the effectiveness of antegrade techniques in treatment of small stones; Stent to patients after antegrade ureteric instrumentation from risk of ureteric stricture formation; Usefulness of laparoscopic ureterolithomy for stone surgeon.

Apple orchards occupy approximately 12,565 ha of land in Ontario, Canada, and are treated with the greatest number and applications of pesticides among all agricultural crops within the province. The potential for exposure to wildlife from frequent organophosphorus (OP) spray applications is therefore considerable. This study investigated theimpact of agricultural spray applications of azinphos-methyl, diazinon, phosalone, and phosmet in apple orchards on the cholinesterase (ChE) activity of wild birds nesting in orchards. These four OP pesticides ranked among the most widely used insecticides used on all fruit crops in Ontario in 1988. Tree swallows (Tachycineta bicolor) and eastern bluebirds (Sialia sialis) were chosen as monitor species becausethey commonly breed and forage within apple orchards, utilize different feeding strategies, and are readily attracted to nest boxes. Brain and plasma ChE activities were determined for nestling bluebirds and swallows, and plasma ChE was measured in adult swallows for comparison with nestling data. In adult tree swallows, mean plasma ChE levels were significantly inhibited 41% compared to controls 12 h after a second application of azinphos-methyl. Mean plasma ChE activity in another group of adult tree swallows dropped by 21 and 19% following a multiple phosmet application, In nestlings, brain ChE activities obtained postspray often fell below predicted activities calculated from control siblings. This trend was especially apparent in the younger nestlings, less than 6 d old. However, for bluebirds the rates of increase of brain ChE with age in nestlings from treated sites was significantly lower than in nestlings from control sites. Brain ChE activity of two nestlings found dead following a phosalone application gave no indication that insecticide exposure was responsible. No other dead or moribund birds were discovered during the course of the study. Sequential plasma sampling of siblings, before and after OP application, [ABSTRACT FROM AUTHOR]

The common loon (Gavia immer) is a high-trophic-level, long-lived, obligate piscivore at risk from elevated levels of Hg through biomagnification and bioaccumulation. From 1991 to 1996 feather (n = 455) andblood (n = 381) samples from adult loons were collected between Juneand September in five regions of North America: Alaska, northwesternUnited States, Upper Great Lakes, New England, and the Canadian Maritimes. Concentrations of Mg in adults ranged from 2.8 to 36.7 mu g/g (fresh weight) in feathers and from 0.12 to 7.80 mu g/g (wet weight) in whole blood. Blood Hg concentrations in 3 to 6-week-old juveniles ranged from 0.03 to 0.78 mu g/g (wet weight) (n = 183). To better interpret exposure data, relationships between blood and feather Hg concentrations were examined among age and sex classes. Blood and featherHg concentrations from the same individuals were significantly correlated and varied geographically (r2 ranged from 0.03 to 0.48). Blood and feather Hg correlated strongest in areas with the highest blood Hg levels, indicating a possible carryover of breeding season Hg that is depurated during winter remigial molt. Mean blood and feather Hg concentrations in males were significantly higher than concentrations in females for each region. The mean blood Hg concentration in adults was 10 times higher than that in juveniles, and feather Hg concentrations significantly increased over 1 to 4-year periods in recaptured individuals. Geographic stratification indicates a significant increasing regional trend in adult and juvenile blood Hg concentrations from west to east. This gradient resembles U.S. EnvironmentalProtection Agency-modeled predictions of total anthropogenic Hg deposition across the United States. This gradient is clearest across regions. Within-region blood Hg concentrations in adults and juveniles across nine sites of one region, the Upper Great Lakes, were less influenced by variations in geographic Hg deposition than by hydrology and lak [ABSTRACT FROM AUTHOR]

It has been suggested that learning an object's location relative to (1) intramaze landmarks and (2) local boundaries is supported by parallel striatal and hippocampal systems, both of which rely upon input from a third system for orientation. However, little is known about the developmental trajectories of these systems' contributions to spatial learning. The present study tested 5- and 7-year-old children and adults on a water maze-like task in which all three types of cue were available. Participants had to remember the location of an object hidden in a circular bounded environment containing a moveable intramaze landmark and surrounded by distal cues. Children performed less accurately than adults, and showed a different pattern of error. While adults relied most on the stable cue provided by the boundary, children relied on both landmark and boundary cues similarly, suggesting a developmental increase in the weighting given to boundary cues. Further, adults were most accurate in coding angular information (dependent on distal cues), whereas children were most accurate in coding distance, suggesting a developing ability to use distal cues to orient. These results indicate that children as young as 5 years use boundary, intramaze landmark, and distal visual cues in parallel, but that the basic accuracy and relative weighting of these cues changes during subsequent development.

Williams syndrome (WS) is a genetic disorder associated with severe visuocognitive impairment. Individuals with WS also report difficulties with everyday wayfinding. To study the development of body-, environment-, and object-based spatial frames of reference in WS, we tested 45 children and adults with WS on a search task in which the participant and a spatial array are moved with respect to each other. Although individuals with WS showed a marked delay, like young controls they demonstrated independent, additive use of body- and environment-based frames of reference. Crucially, object-based (intrinsic) representations based on local landmarks within the array were only marginally used even by adults with WS, whereas in typical development these emerge at 5 years. Deficits in landmark use are consistent with wayfinding difficulties in WS, and may also contribute to problems with basic localization, since in typical development landmark-based representations supplement those based on the body and on self-motion. Difficulties with inhibition or mental rotation may be further components in the impaired ability to use the correct reference frame in WS.