bluuebunny/crossref_metadata_2025_split huggingface dataset:
The conflict between vervet monkeys and farmers at the forest edge in Entebbe, Uganda
Authors: Saj Tania L. , Sicotte Pascale , Paterson J. D. 
Published: March 2003

AbstractForty‐seven property owners in Entebbe, Uganda were questioned about vervet monkey activities on their property. Our main objective was to investigate the interactions between humans and vervet monkeys in an agricultural area adjacent to a forest zone. Other studies have reported that farms located within 300 m of a forested boundary probably incur the greatest risk of crop‐raiding. Two other factors that may influence susceptibility to vervet crop‐raiding were also examined: the types of crops grown and the types of direct preventative measures used. The effect of these two factors on vervet crop‐raiding is not straightforward. However, the distance a property is located from the forest edge is an important factor influencing vervet crop‐raiding. Surveyed gardens 200 m from the forest edge received significantly less crop‐raiding than farms located 100 m or 50 m (P = 0.040, < α = 0.05). We suggest that the development of nonagricultural activities on land directly adjacent to forested areas may reduce vervet crop‐raiding by deterring vervets from travelling greater distances from the forest edge due to increased obstacles or risks.
The East Usambara tree‐hole crab (Brachyura: Potamoidea: Potamonautidae) − a striking example of crustacean adaptation in closed canopy forest, Tanzania
Authors: Bayliss J. 
Published: March 2003

AbstractAn undescribed species of freshwater crab with a remarkable life history was studied over 2 years in areas of natural forest in the East Usambara Mountains, north‐east Tanzania. It was found occupying the water‐filled boles (tree holes) of several tree species at altitudes between 150 and 900 m asl, a single tree species Myrianthus holstii accounted for 26% of all trees identified as such. There was no apparent association with other freshwater bodies. The ‘tree‐hole crab’ is largely nocturnal but will also forage by day during periods of heavy rainfall, leaving its tree hole in search of leaf‐litter molluscs. Once located it carries pieces of the snail shell back to the tree hole and releases these into the water filled bole which is typically acidic. This releases calcium ions (Ca2+) into solution from the snail shell resulting in a more neutral solution (mean pH = 6.6, standard deviation (s) = 0.46, n = 25). This act provides a source of dissolved calcium for the development of exoskeletons following ecdysis. Significant differences were found between depth (P = 0.01) and height (P = 0.05) of occupied and unoccupied water‐filled tree holes. This is the first record of a crab exhibiting such behaviour in East Africa.
Assessment of the woody vegetation of Ol Choro Oiroua, Masai Mara, Kenya
Authors: Van Essen L. D. , Bothma J. du P. , Van Rooyen N. , Trollope W. S. W. 
Published: March 2003

AbstractThe woody vegetation of the Ol Choro Oiroua Wildlife Management and Conservation area was surveyed. The species present, their size and the vertical distribution of their canopy were recorded. These parameters were then used to determine the percentage cover of woody vegetation at different heights, and the potential productivity of the trees and shrubs in terms of the available browse material. The survey data were converted to Browse Tree Equivalents, Leaf Dry Mass and a Canopy Sub‐habitat Index, using the Browse Estimate from the Canopy Volume (Becvol) program. These parameters were next used to assess and predict the potential production of available browse material. The assessment established permanent observation plots for browse productivity estimates, and to serve as a basis for monitoring the encroachment or decline of woody species in the region.
Effect of ipriflavone on pain due to recent osteoporotic vertebral crush fracture
Authors: Rahman Mohammad M. , Haq Syed A. , Alam Mohammad N. , Chowdhury Mohammad A. J. 
Published: March 2003

Abstract Aim: Ipriflavone conserves bone mass in postmenopausal osteoporosis. Salmon calcitonin and alendronate, two other anti‐resorptive drugs, have been found to have analgesic effects in osteoporotic acute vertebral fracture. This study aimed to determine if ipriflavone also possesses such an effect. Methods: Thirty‐two women with recent osteoporotic vertebral fractures were randomly assigned to ipriflavone treatment or placebo groups. Ipriflavone was given at the dose of 200 mg three times a day. Non‐steroidal anti‐inflammatory drugs were given ad libitum in both groups. Calcium carbonate (1 g daily) was administered to all subjects. Intensity of pain at rest, on movement and on pressure, pain rating on a 10‐point visual analogue scale, degree of mobility impairment, and supplementary analgesic were assessed at the end of a 3‐month period in both groups to assess the analgesic effect of ipriflavone. Results: Fourteen subjects in the ipriflavone group and 12 in the placebo group completed the trial. After 3 months, all pain variables had decreased significantly in both groups. Intensity of pain at rest and on pressure and supplementary analgesic use were significantly lower in the ipriflavone group compared to the placebo group. Conclusion: The study shows that ipriflavone has an analgesic adjuvant effect in acute osteoporotic vertebral fracture.
Growth conditions are more important than species origin in determining leaf pigment content of British plant species
Authors: Rosevear M. J. , Young A. J. , Johnson G. N. 
Published: March 2003

Summary

This paper describes a study of 23 plant species native to the British Isles, to investigate the relative importance of growth conditions and ecological origin in determining the content and composition of the photosynthetic pigments (chlorophylls and carotenoids) within leaves.
The species studied reflected a range of ecological types, from deep shade to full sun.
Plants were grown in two light environments: high light (HL), filtered through a clear filter; and low light (LL), filtered through a neutral density filter which reduced total irradiance with enhanced far‐red.
Plants grown at high irradiance contained more carotenoid per unit chlorophyll and showed a marked increase in xanthophyll cycle pigments relative to other carotenoids.
Deep‐shade plants were slightly less responsive to changes in growth light conditions than plants native to less shaded locations. Intermediate sun/shade plants were slightly more responsive; however these differences were small compared with the extent of the response of all species to HL vs LL.
The main conclusion is that that the light conditions to which the plants are exposed are more important than the genetic predisposition of those plants in determining the pigment content and composition of leaves.
Strategy shifts in leaf physiology, structure and nutrient content between species of high‐ and low‐rainfall and high‐ and low‐nutrient habitats
Authors: Wright I. J. , Reich P. B. , Westoby M. 
Published: March 2003

Summary

Relationships were examined among photosynthetic capacity (Amass and Aarea), foliar dark respiration rate (Rd‐mass and Rd‐area), stomatal conductance to water (Gs), specific leaf area (SLA), and leaf nitrogen (N) and phosphorus (P) across 79 perennial species occurring at four sites with contrasting rainfall levels and soil nutrients in eastern Australia. We hypothesized that the slope of log–log ‘scaling’ relationships between these traits would be positive and would not differ between sites, although slope elevations might shift between habitat types.
Amass, Rd‐mass, SLA, Nmass and Pmass were positively associated in common slopes fitted across sites or rainfall zones, although rather weakly within individual sites in some cases. The relationships between Amass (and Rd‐mass) with each of Nmass and SLA were partially independent of each other, with Amass (or Rd‐mass) increasing with SLA at a given Nmass, or with Nmass at a given SLA (only weakly in the case of Amass). These results improve the quantification and extend the generalization of reported patterns to floras largely unlike those studied previously, with the additional contribution of including phosphorus data.
Species from drier sites differed in several important respects. They had (i) higher leaf N and P (per dry mass or area); (ii) lower photosynthetic capacity at a given leaf N or P; (iii) higher Rd‐mass at a given SLA or Amass; and (iv) lower Gs at a given Aarea (implying lower internal CO2 concentration).
These trends can be interpreted as part of a previously undocumented water conservation strategy in species from dry habitats. By investing heavily in photosynthetic enzymes, a larger drawdown of internal CO2 concentration is achieved, and a given photosynthetic rate is possible at a lower stomatal conductance. Transpirational water use is similar, however, due to the lower‐humidity air in dry sites. The benefit of the strategy is that dry‐site species reduce water loss at a given Aarea, down to levels similar to wet‐site species, despite occurring in lower‐humidity environments. The cost of high leaf N is reflected in higher dark respiration rates and, presumably, additional costs incurred by N acquisition and increased herbivory risk.
Growth‐enhanced fish can be competitive in the wild
Authors: Johnsson J. I. , Björnsson B. TH. 
Published: March 2003

Summary The widespread commercial interest in producing growth‐enhanced organisms has raised concerns about ecological consequences, emphasizing the need to understand the costs and benefits associated with accelerated growth in nature. Here, sustained‐release growth hormone (GH) implants were used to estimate the competitive ability of growth‐enhanced fish in the wild. Growth rate, movements and survival over winter were compared between GH‐implanted and control Brown Trout in a natural stream. The study was repeated over two consecutive years. GH treatment had no effect on recapture rates, indicating that mortality rates did not differ between GH‐treated and control fish. More GH‐treated trout (63%) than control fish (41%) were recaptured within their 10 m section of release. Thus, GH‐treated fish were more stationary than control fish over winter. GH‐treated fish grew about 20% faster than control fish. This was mainly because of a three‐fold growth rate increase in GH‐treated fish in late summer, whereas growth rates over winter did not differ significantly between treatment groups. These results were consistent over both replicate years. This first study of growth‐enhanced fish in the wild shows that they can survive well and therefore may out‐compete normal fish with lower growth rates. Although selection against rapid growth may be more intense at other life‐history stages and/or during periods of extreme climate conditions, our findings raise concerns that released or escaped growth‐enhanced salmonids may compete successfully with resident fish. It is clear that the potential ecological risks associated with growth‐enhanced fish should not be ignored.
Body size, locomotor speed and antipredator behaviour in a tropical snake (Tropidonophis mairii, Colubridae): the influence of incubation environments and genetic factors
Authors: Webb J. K. , Brown G. P. , Shine R. 
Published: March 2003

Summary

The physical conditions experienced by reptile embryos inside natural nests can influence the size, shape and behaviour of the resultant hatchlings. Although most reptiles are tropical, the effects of incubation temperatures on offspring phenotypes have received little attention in tropical species.
The consequences of differences in thermal variance during incubation on offspring were studied in a tropical natricine snake (the Keelback Tropidonophismairii), which lays eggs in soil cracks of varying depths. Some 253 eggs from 19 clutches were incubated under two thermal regimes with identical mean temperatures (25·6 °C), but temperatures in the ‘variable’ treatment fluctuated more (21·8–29·6 °C) than those in the ‘constant’ temperature treatment (25·2–26·5 °C). These thermal regimes were similar to those of shallow (20 cm deep) and deep (40 cm deep) soil cracks, respectively, and represent thermal conditions inside natural nests and potential nest sites.
Incubation temperatures affected body size, shape and antipredator behaviour of hatchling snakes. Snakes from constant temperature incubation were longer and thinner than snakes from high variance incubation. Clutch effects influenced all offspring traits, with significant interactions between clutch of origin and incubation treatment for body size, but not swimming speed or behaviour.
There was a significant interaction between incubation treatment and offspring sex on neonate swimming speed. Incubation under cycling thermal regimes significantly increased swimming speeds of females, but had little effect on males. Such sex differences in phenotypic responses of hatchling snakes support a major assumption of the Charnov–Bull hypothesis for the evolution of temperature‐dependent sex determination.
Photosynthetic adaptation and acclimation to exploit seasonal periods of direct irradiance in three temperate, deciduous‐forest herbs
Authors: ROTHSTEIN D. E. , ZAK D. R. 
Published: March 2003

Summary

We evaluated the potential for three species of deciduous‐forest herbs to exploit seasonal periods of direct irradiance. In particular, we investigated the importance of photosynthetic acclimation as a mechanism for shade‐tolerant herbs to utilize direct light reaching the forest floor before canopy expansion in the spring and after canopy leaf drop in the autumn.
We measured the photosynthetic and growth characteristics of three co‐occurring herbs of a northern hardwood forest: the spring ephemeral Allium tricoccum Ait., the summer‐green Viola pubescens Ait., and the semi‐evergreen Tiarella cordifolia L.
Leaf CO2 exchange, leaf mass per area, and leaf biochemistry differed among species and seasonally within species to match the changing light environment below the forest canopy. From spring to summer, as irradiance dropped with the expansion of the overstorey canopy, Viola leaves exhibited reduction of both photosynthetic capacity and light compensation point. Weaker acclimation of less magnitude occurred in Tiarella leaves over the spring–summer light transition; this was followed by further acclimation to the stronger autumn irradiance.
Viola’s greater range of photosynthetic acclimation was associated with shifts in allocation between Rubisco and chlorophyll, as well as changes in total leaf nitrogen (N) concentration and leaf mass per area (LMA). In contrast, Tiarella’s narrow range of acclimation was associated solely with changes in allocation to Rubisco versus chlorophyll, with no changes in total leaf N or LMA.
Seasonal changes in leaf chemistry and structure in Viola suggest a stepwise ontogeny whereby individual leaves are able to function as ‘sun leaves’ for 3–5 weeks in the spring, and then as ‘shade leaves’ for up to 3 months in the summer.
Whole‐plant biomass accumulation showed that all three species accumulated most of their annual biomass increment during periods of direct irradiance. These results demonstrate the importance of brief seasonal periods of strong irradiance to the growth of deciduous forest herbs, even shade‐tolerant, summer and evergreen species.
Clinical experience of amiodarone‐induced thyrotoxicosis over a 3‐year period: role of colour‐flow Doppler sonography*
Authors: Eaton S. E. M. , Euinton H. A. , Newman C. M. , Weetman A. P. , Bennet W. M. 
Published: March 2003

Summaryobjective Current thinking is that amiodarone‐induced thyrotoxicosis (AIT) might be either iodine‐induced thyrotoxicosis in latent hyperthyroidism (Type 1) or destructive thyroiditis (Type 2), and also that colour‐flow Doppler sonography (CFDS) of the thyroid and serum interleukin 6 (IL‐6) are tools that can classify AIT and direct treatment. To assess the validity of this thinking, our objective was to determine whether CFDS and IL‐6 identified AIT subgroups with distinct features.design Retrospective case‐note audit of all patients presenting with AIT to the Endocrine Department of a UK teaching hospital over a 3‐year period. To assess proportions of Type 1 vs. Type 2 AIT and to compare and contrast their clinical features.patients 37 patients were identified with AIT (mean age 65, range 20–86 years). In 30 patients in whom AIT persisted, 25 underwent CFDS.results In 25 patients who underwent CFDS, 10 (40%) were classified as Type 1, 10 (40%) as Type 2 and 5 (20%) as indeterminate type. In the patients classified by CFDS in whom AIT persisted, 40% of Type 1 patients were male vs. 90% of Type 2 patients. Also, free T4 tended to be lower in patients presenting with Type 1 AIT (52·1 ± 7·5 pmol/l) compared to Type 2 (74·8 ± 8·1 pmol/l, P = 0·08), free T3 was lower (8·8 ± 0·9 vs. 15·6 ± 3·0 pmol/l, P = 0·03) and the cumulative amiodarone dose was lower (66 ± 20 vs. 186 ± 28 g, P = 0·002). We used less prednisolone to achieve euthyroidism in patients with Type 1 AIT whereas carbimazole doses were not different and the time to euthyroidism was the same in both groups (81 ± 21 vs. 88 ± 13 days). IL‐6 was raised in two patients with Type 1 and in one patient with Type 2 AIT.conclusions CFDS could characterize two distinct subtypes in patients with AIT. Conversely, IL‐6 seemed to be an unhelpful test in this context.
The effects of cimetidine and antacid on the pharmacokinetic profile of sildenafil citrate in healthy male volunteers
Authors: Wilner Keith , Laboy Lucia , LeBel Marc 
Published: March 2003

Aims  To examine the effect of concomitant cimetidine or antacid administration on the pharmacokinetic profile of sildenafil citrate in healthy male volunteers in two open‐label, randomized studies.Methods  The first study was a parallel‐group design in which 22 healthy male volunteers received sildenafil (50 mg) on days 1 and 5 and cimetidine (800 mg) or placebo on days 3, 4, 5, and 6. Blood samples were collected predose and at specified times up to 48 h postdose on days 1 and 5 to determine plasma levels of sildenafil and its metabolite, UK‐103,320. The second study was a two‐way crossover design in which 12 volunteers received sildenafil with or without a 30‐ml dose of a magnesium hydroxide/aluminium hydroxide antacid. Blood samples were collected and analysed as in the first study. The two study periods were separated by at least 14 days.Results  Coadministration of cimetidine had no statistically significant effect on the tmax or kel of sildenafil but caused a statistically significant increase in sildenafil AUCt and Cmax of 56% and 54%, respectively (P<0.01). Differences between the two treatment groups were smaller for the metabolite than for sildenafil, although cimetidine treatment did significantly (P<0.05) increase the AUCt for UK‐103,320 by 30%. Antacid coadministration had no statistically significant effect on any pharmacokinetic parameter of sildenafil or UK‐103,320. Whether taken alone, with cimetidine, or with an antacid, sildenafil was well tolerated. Most adverse events were mild in nature, and no subject withdrew from either study for any reason related to the drug.Conclusions  Cimetidine co‐administration produced an increase in sildenafil plasma levels; however, this increase is not sufficient to warrant dosage adjustment of either drug. Antacid coadministration had no effect on the pharmacokinetic profile of sildenafil.
Drug therapy in the elderly: what doctors believe and patients actually do
Authors: Barat I. , Andreasen F. , Damsgaard E. M. S. 
Published: March 2003

Aims  To examine the medication adherence among old persons living in their own homes, to assess their knowledge of their medication, and to indicate target areas for intervention.Methods  A cross‐sectional study of data collected from randomly selected samples of 348 persons, aged 75 years recruited from a population‐based register in the municipality of Aarhus, Denmark. Information on all drugs was collected from the subjects during a home visit, and their drug storage was examined. Information was collected from the general practitioners (GP). The measures of adherence were scores of agreements between the GPs' lists and the subjects' actual drug consumption.Results  We found disagreement between the drug information collected from the study population and from the GPs: concerning drugs in 22% of the study‐population, concerning doses in 71%, and concerning regimens prescribed by the GP in 66%. Twenty‐four percent stated that they did not always follow prescriptions. Most of the deviations from prescriptions were toward lower doses and less frequent drug intake. The drugs most often involved in deviations were hypnotics, analgesics, bronchodilators and diuretics. Sixty percent of the participants knew the purpose of medication, and 21% knew the consequences of omission of the drugs. Less than 6% of the subjects knew about the toxic risks, side‐effects, or potential drug interactions. The participants' knowledge of the drugs was positively associated with their adherence. We found a correlation between an increased number of prescribed frequency of drug intake per day and deviation from the regimen (r = 0.25, P = 0.01). There was a positive association between nonadherence and the use of three or more drugs (odds ratio (OR) 2.5; 95% confidence interval (CI) 1.5,4.1), prescriptions from more than one doctor (OR 2.5; 95% CI 1.3,4.8), and probability of dementia (OR 9.0; 95% CI 1.1,72.5). Moreover compliance aids facilitated adherence (OR 4.4; 95% CI 1.6,12.3). Persons living alone were more prone to medication errors (OR 2.0; 95% CI 1.1,3.5).Conclusions  A differentiated evaluation of adherence by considering the drug, the dose, and the regimen separately produced quantifiable data concerning the subjects' medication habits. Non‐adherence ranged from 20 to 70% depending on the measuring method. The participants' knowledge of the treatment was poor. Our results suggest that better information on medication and the use of compliance aids may prevent nonadherence. Special attention should be paid to persons receiving three or more drugs, living alone, receiving drugs from other doctors, and to persons with predementia symptoms, as they are at higher risk of nonadherence.