bluuebunny/crossref_metadata_2025_split huggingface dataset:
Do elephants over-utilize mopane woodlands in northern Botswana?
Authors: Ben-Shahar Raphael 
Published: July 2009

ABSTRACTEvidence from southern African semi-arid savannas suggests that high elephant densities in nature reserves cause the over-utilization of woodlands. Northern Botswana, with its prolific elephant population, is expected to follow such a pattern unless the densities of elephants which could be sustained by indigenous woodlands are determined and maintained at carrying capacity. Above ground biomass production was estimated for mopane (Colophospermum mopane) woodlands, a principal food source for elephants, which grows over much of northern Botswana. Densities of trees and shrubs, dimensions of plants and elephant densities were recorded within stratified plots situated according to a regional rainfall gradient. Mean estimates of above ground biomass (foliage and twigs) were 9.41 and 7.83 t ha−1 for shrubs and trees respectively. A logistic model described the maximum levels of biomass removal from plants before over-utilization of mopane occurred. Variables incorporated in the model included above ground biomass of mopane shrubs and trees, growth rates of plants and expected off-take by elephants. The model predicted a complete biomass regain within 10 y if no elephant browsing occurs. Intensive elephant browsing in woodlands containing 15 elephants km−2, however, can suppress biomass production if growth rates of plants fall below 70% of the maximum annual rate. Nonetheless, there was no substantial evidence to suggest that elephants will reduce the biomass of mopane woodlands in northern Botswana below a sustainable level if their numbers are allowed to increase considerably beyond the current estimate.
Seed viability of Afromontane tree species in forest soils
Authors: Teketay Demel , Granström Anders 
Published: July 2009

ABSTRACTThe fate of seeds of eight tree species was followed during 4 y of storage in the soil of an Afromontane forest at Gara Ades in the eastern highlands of Ethiopia. Seeds were enclosed in nylon mesh bags and buried at 5 cm soil depth. The bags were exhumed at intervals and the viability of the seeds was assessed by germination and cutting tests. Seeds ofBersama abyssinicaandEkebergia capensisgerminated in the soil almost completely within a year after burial. The seeds ofJuniperus procera, Olea europaeaandPodocarpus falcatusalso germinated to a substantial degree in the soil but with a distribution over several years, and some seeds of these species remained viable at the end of the 4-y period. Germination in the soil was very low in seeds ofAcacia abyssinicaandCroton macrostachyusthroughout the whole burial period and the seeds kept their viability. InC. macrostachyusfresh seeds were highly dormant, but after 3 y or more in the soil they germinated readily in the laboratory suggesting an altered dormancy with time in the soil. Dormancy in seeds ofA. abyssinicaandIndigofera rothiiwas not altered throughout the study period as evidenced by marginal or no germination during incubation in the laboratory. The differential seed behaviour observed during storage in the soil can be an indicator of the regeneration strategy of the species studied.B. abyssinica, E. capensis, J. procera, O. europaeaandP. falcatusform seedling banks on the forest floor and lack persistent soil seed reserves in contrast toA. abyssinica, C. macrostachyusandI. rothiiwhich accumulate reserves of long-lived seeds in the soil. The generally high levels of dormancy and somewhat extended viability in the soil, even in several of the species producing seedlings in undisturbed forest, may have been selected for under a climate of seasonal drought and unreliable rainfall that characterizes this region.
Altitudinal zonation of rain forest on Bukit Belalong, Brunei: soils, forest structure and floristics
Authors: Pendry Colin A. , Proctor John 
Published: July 2009

ABSTRACTBukit Belalong, Brunei, is a small mountain (913 m) of uniform shale lithology with continuous primary rain forest from its base to its summit. Three 0.25 ha plots were established at each of three altitudes (200, 500 and 850 m) to investigate the altitudinal zonation of the soils and the vegetation. One soil profile from each altitude is described and chemical analyses of the soils indicate that they are similar at all altitudes. In each plot all trees ≥10 cm dbh were measured and identified as far as possible. Maximum tree height was greatest at 200 m (60 m) and least at 850 m (33 m). Tree density (number of individuals ha−1) increased with altitude. The forest at 850 m was the most species- and family-rich, but since the ratio of species to individuals did not vary significantly among altitudes, the higher species richness is attributed partly to the larger number of trees sampled. The Dipterocarpaceae was the most important family in terms of basal area at all altitudes, but its proportion of basal area was much smaller at 850 m than at the other altitudes. The Dipterocarpaceae was the most diverse family at 200 m and 500 m, but at 850 m its diversity was exceeded by the Lauraceae, Myrtaceae and Euphorbiaceae and equalled by the Clusiaceae. The forests at 200 m and 500 m are classified as lowland rain forest and that at 850 m is classified as a lower montane forest.
Seed predation in a tropical mangrove forest: a test of the dominance-predation model in northern Australia
Authors: McGuinness Keith A. 
Published: July 2009

ABSTRACTStudies of predation on propagules of the mangroves Avicennia marina, Bruguiera exaristata, Ceriops tagal and Rhizophora stylosa were made in a forest in northern Australia to test the generality of the dominance-predation model. This model states that an inverse relationship exists between the dominance of a species in the canopy of mangrove forests and the rate of predation on the propagules of that species. Significant differences in predation were found among the four species, and among patches of forest dominated by the different species. Predators attacked more than 50% of the propagules of all species except R. stylosa, so are likely to significantly affect forest structure. The intensity of predation did not, however, vary as the dominance-predation model predicted. Instead, predation on the propagules of a species appeared to depend on the availability of propagules of other, more highly preferred, species.
Reproductive allocation and pollinator distributions in cauliflorus trees in Trinidad
Authors: Warren John M. , Emamdie Debbie Z. , Kalai  
Published: July 2009

ABSTRACTLittle information is available to test the various theories which have been proposed to explain the evolution of cauliflory. This study provides such data from observations in Trinidad of the numbers of potential pollinators visiting trunk and canopy flowers and on the size of canopy and trunk flowers and fruits. Subsidiary observations were made on the partitioning of resources between the sexes within flowers. Significantly more potential insect pollinators were trapped around the trunk flowers of two cauliflorous species than were caught around their canopy flowers. Trunk flowers were found to be larger than canopy flowers in four of the seven cauliflorous species studied, but they were smaller in one species. The higher probability of fruit set on trunks than in the canopy may have selected for cauliflory and subsequently increased trunk flower size in insect-pollinated understorey tropical trees. There was a tendency for flowers on the trunk not only to be larger but also to allocate relatively more dry weight to female parts and result in larger fruit than those in the canopy. These observations are consistent with Wallace's theory of the evolution of cauliflory, which argues that the condition arose in the dark understorey of the tropical forest, as a result of selection for trunk flowers which are more apparent to pollinators than are canopy flowers. However, other explanations for the evolution of cauliflory are not precluded as they are not mutually exclusive.
Mass and nutrient dynamics of decaying litter fromPassiflora mollissimaand selected native species in a Hawaiian montane rain forest
Authors: Scowcroft Paul G. 
Published: July 2009

ABSTRACTThe structure and functioning ofAcacia koa-Metrosideros polymorphaforests between 1200 and 1800 m elevation on the island of Hawaii are being threatened byPassiflora mollissima, an aggressive introduced liana from South America. This study was done to evaluate the short-term decomposition dynamics ofPassifloraand selected native leaf and twig litter. The nutrient-rich, non-sclerophyllousPassifloraleaves completely disappeared in less than 5 mo. The estimated time for native leaf litter to lose 95% of initial dry weight ranged from 1.65 y for N-richAcaciaphyllodes to 6.67 y forCibotium glaucum; for woody litter, the time ranged from 4.5 y forAcaciatwigs to 23 y forAcaciabark. Except forCibotiumfrond litter, decay rates were significantly correlated with initial lignin-ash ratios.Passifloralitter did not accelerate decomposition ofAcaciaandMetrosiderosleaf litter.Passiflora, Acacia, andMetrosiderosleaf litter showed net mineralization of N, P, Ca, K, and Mg during the study.Cibotiumfrond litter showed significant accumulation of N, Ca, and Mg; P levels stayed constant and K was rapidly lost. In general, twigs experienced a net loss of most nutrients, while bark experienced either no change or a significant net gain of nutrients. Nutrient cycling has increased inP. mollissimainfested forests.
The distribution of organic carbon in major components of forests located in five life zones of Venezuela
Authors: Delaney M. , Brown S. , Lugo A. E. , Torres-Lezama A. , Quintero N. Bello 
Published: July 2009

ABSTRACTOne of the major uncertainties concerning the role of tropical forests in the global carbon cycle is the lack of adequate data on the carbon content of all their components. The goal of this study was to contribute to filling this data gap by estimating the quantity of carbon in the biomass, soil and necromass for 23 long-term permanent forest plots in five life zones of Venezuela to determine how C was partitioned among these components across a range of environments. Aboveground biomass C ranged from 70 to 179 Mg ha−1and soil C from 125 to 257 Mg ha−1, and they represented the two largest C components in all plots. The C in fine litter (2.4 to 5.2 Mg ha−1), dead wood (2.4 to 21.2 Mg ha−1) and roots (23.6 to 38.0 Mg ha−1) accounted for less than 13% of the total C. The total amount of C among life zones ranged from 302 to 488 Mg ha−1, and showed no clear trend with life zone. In three of the five life zones, more C was found in the dead (soil, litter, dead wood) than in the live (biomass) components (dead to live ratios of 1.3 to 2.3); the lowland moist and moist transition to dry life zones had dead to live ratios of less than one. Results from this research suggest that for most life zones, an amount equivalent to between 20 and 58% of the aboveground biomass is located in necromass and roots. These percentages coupled with reliable estimates of aboveground biomass from forest inventories enable a more complete estimation of the C content of tropical forests to be made.
High-resolution reflecting time-of-flight momentum and energy mapping system
Authors: Wang Chao , Kang Yifan , Weaver Larry , Chang Zenghu 
Published: July 2009

A new system to map electron momentum and energy is proposed. A reflecting electrode is introduced into a time-of-flight (TOF) system whose decelerating electric field sends all the electrons back to a position-sensitive detector close to but behind the source of the electrons. The longer flying distance that results makes it possible to significantly improve the energy-resolved performance, especially in the higher energy region. The dependence of the new TOF system on its characteristic parameters is analyzed, along with its application to attosecond streak cameras. Experimental results verified a relative energy resolution better than 0.2 eV for 22 eV electrons and also revealed the availability of the improved relative energy resolution smaller than 1.0% for electron energy ranging from 30 to 40 eV.
At the request of the authors and editor, this article is being retracted effective 4 September 2009.
Bryozoan populations reflect nutrient enrichment and productivity gradients in rivers
Authors: HARTIKAINEN HANNA , JOHNES PENNY , MONCRIEFF CLIVE , OKAMURA BETH 
Published: July 2009

Summary1. The hypothesis that nutrient enrichment will affect bryozoan abundance was tested using two complementary investigations; a field‐based method determining bryozoan abundance in 20 rivers of different nutrient concentrations by deploying statoblast (dormant propagule) traps and an experimental laboratory microcosm study measuring bryozoan growth and mortality. These two methods confirmed independently that increased nutrient concentrations in water promote increases in the biomass of freshwater bryozoans.2. Statoblasts of the genus Plumatella were recorded in all rivers, regardless of nutrient concentrations, demonstrating that freshwater bryozoans are widespread. Concentrations of Plumatella statoblasts were high in rivers with high nutrient concentrations relative to those with low to moderate nutrient concentrations. Regression analyses indicated that phosphorus concentrations, in particular, significantly influenced statoblast concentrations.3. Concentrations of Lophopus crystallinus statoblasts were also higher in sites characterised by high nutrient concentrations. Logistic regression analysis revealed that the presence of L. crystallinus statoblasts was significantly associated with decreasing altitude and increasing phosphorus concentrations. This apparently rare species was found in nine rivers (out of 20), seven of which were new sites for L. crystallinus.4. Growth rates of Fredericella sultana in laboratory microcosms increased with increasing nutrient concentration and high mortality rates were associated with low nutrient concentrations.5. Our results indicate that bryozoans respond to increasing nutrient concentrations by increased growth, resulting in higher biomasses in enriched waters. We also found that an important component of bryozoan diets can derive from food items lacking chlorophyll a. Finally, bryozoans may be used as independent proxies for inferring trophic conditions, a feature that may be especially valuable in reconstructing historical environments by assessing the abundance of statoblasts in sediment cores.
Observed relationships between El Niño‐Southern Oscillation, rainfall variability and vegetation and fire history on Halmahera, Maluku, Indonesia
Authors: VAN DER KAARS SANDER , TAPPER NIGEL , COOK ELLYN J. 
Published: July 2009

AbstractA temporally high‐resolution palynological study of the uppermost section of core MD98‐2180 from Kau Bay, Halmahera, Indonesia, provides a vegetation and fire record covering the last 250 years. The record is compared with the Maluku Rainfall Index, Southern Oscillation Index (SOI) and southern hemisphere winter sea surface temperatures (SST) for the central Pacific Ocean based on instrumental data, as well as reconstructions of the SOI and the central Pacific SST and historically recorded El Niño events. The results show that significant El Niño events are generally associated with increased representation of Dipterocarpaceae pollen, probably reflecting the mass‐flowering of this taxon during El Niño‐Southern Oscillation (ENSO) droughts, and elevated charcoal levels, reflecting a greater incidence of fires during these extremely dry periods, while humid phases show increased fern numbers. Our findings demonstrate that pollen records ‘ecological’ in scale can provide useful additional proxy records of ENSO events.
Immunophenotypic features of MELF pattern invasion in endometrial adenocarcinoma: evidence for epithelial–mesenchymal transition
Authors: Stewart Colin J R , Little Leonie 
Published: July 2009

Aims:  Endometrial endometrioid adenocarcinomas (EEC) may show a distinctive morphological alteration characterized by the presence of microcystic, elongated and fragmented (‘MELF’) glands. These changes share features of epithelial–mesenchymal transition (EMT) in carcinomas arising at other sites. The aim was to compare the immunophenotypic profile of MELF‐type epithelium with conventional glandular areas of EEC.Methods and results:  Twenty‐one EEC were stained immunohistochemically for cytokeratin (CK) AE1/AE3, CK7, vimentin, oestrogen receptor, progesterone receptor and E‐cadherin. Conventional tumour glands usually showed preserved membranous E‐cadherin immunoreactivity with peripheral accentuation of vimentin and hormone receptor expression. MELF‐type invasion was characterized by strong CK7 expression, sometimes in contrast to adjacent unstained tumour glands. MELF areas were usually negative for hormone receptors and showed reduced E‐cadherin expression.Conclusions:  The expression of hormone receptors and intermediate filaments shows specific distribution patterns within EEC. MELF pattern invasion shows an altered immunophenotype compared with conventional glandular tumour areas. These findings suggest that MELF‐type invasion represents a specific tumour alteration, and the reduction in hormone receptor and E‐cadherin expression would be consistent with EMT. Immunohistochemical studies of EEC should consider micro anatomical variations in immunoreactivity, since these may be relevant to tumour invasion and progression.
Osmotic dehydration of guava: influence of replacing sodium metabisulphite with honey on quality
Authors: Duangmal Kiattisak , Khachonsakmetee Supaluck 
Published: July 2009

SummaryGuava slices were subjected to pre‐treatment by soaking in a solution containing 0.25% (w/v) sodium metabisulphite, 0.5% (w/v) ascorbic acid, 1% (w/v) citric acid, 1% (w/v) calcium chloride and either 0%, 1% or 3% (v/v) honey. A higher concentration of metabisulphite [0.5% (w/v)], but no honey, was also prepared as a reference. After osmotic dehydration, the guava slices were dried at 60 °C. During 24 weeks of storage, the measured texture values of products indicated that an addition of honey significantly delayed the increase in hardness and cutting work in guava slices compared to other treatments (P ≤ 0.05). Pre‐treatment with 0.5% (w/v) metabisulphite without honey or 0.25% (w/v) metabisulphite with 1% (v/v) honey maintained colour during storage better than with 0 or 3% (v/v) honey. The result showed good agreement with colour score evaluation. Overall results suggested that 1% (v/v) honey was the best pre‐treatment condition.
Behaviour guidance in dental treatment of patients with autism spectrum disorder
Authors: LOO CHEEN Y. , GRAHAM RICHARD M. , HUGHES CHRISTOPHER V. 
Published: July 2009

Background.  Autism spectrum disorder (ASD) is a neurodevelopmental disorder categorized into autism, pervasive developmental disorder – not otherwise specified (PDD‐NOS) and Asperger syndrome.Aims.  To identify factors associated with the behaviour of patients with ASD in a dental setting, use of general anaesthesia (GA), and protective stabilization.Design.  The dental charts of 395 patients with ASD patients and 386 unaffected patients were reviewed. The following data were analysed: ASD diagnosis, age, gender, residence, seizure disorder, additional diagnosis (mental retardation, cerebral palsy, self‐injurious behaviour or pica), medications, caries prevalence and severity, dental treatment history, behaviour, and behaviour guidance technique(s) used.Results.  Within both groups, younger patients were more uncooperative. ASD patients with autism were more uncooperative than patients with PDD‐NOS; patients with an additional diagnosis were also more uncooperative. ASD patients with higher caries severity, who were uncooperative or female, were more likely to require GA. Use of protective stabilization was associated with lower caries severity, presence of seizure disorder, uncooperative behaviour, male gender, or residency in a group home/institution.Conclusions.  Autism spectrum disorder patients with autism, younger age and an additional diagnosis were more uncooperative. Factors associated with the use of GA and protective stabilization in patients with ASD were also identified.
Factors affecting nursing staff in practising spiritual care
Authors: Chan Moon Fai 
Published: July 2009

Aim.  To examine nurses’ attitudes to practising spiritual care and determine factors associated with nurses’ attitudes to practising spiritual care.Background.  Today, health is no longer viewed as a passive state of being, but as a dynamic process of achieving higher levels of wellness. In practices, nurse has increasingly focused on treating the whole person, including the four domains: physical, mental, social and spiritual. Of these four domains, the spiritual domain is the most neglected in daily nursing practice.Design.  This is retrospective study.Methods.  A convenience sampling was used and 110 nurses completed a structured questionnaire at a public hospital in September 2006.Outcome measures.  Nurses’ demographic data and perceptions and practices scores on spiritual care.Results.  The results showed that nurses who more likely had religious beliefs (p = 0·028), were more likely to be married (p = 0·01), had past hospitalisation experiences (p = 0·009), worked in the obstetrics and gynaecology department (p < 0·001) and had higher perception levels towards spiritual care (p < 0·001) were significantly more likely to be practising spiritual care.Conclusion.  As nurses are with patients all day, they are in a position to safeguard the wholeness and integrity of the patient. As mentioned in the results, there is a positive correlation between spiritual care perceptions and spiritual care practice among nurses, which means that the greater the nurse’s spiritual care perceptions, the more frequently spiritual care is included in that nurse’s practice. This correlation is vital and meaningful; it can drive hospitals to promote nurses’ awareness of spiritual care to improve the quality of their spiritual care practice.Relevant to clinical practices.  To facilitate collaboration between nurses and clergy, it might be beneficial for nurses to communicate more with the clergy, include clergy in patient profile discussions and treat clergy as members of the health care team. Given the influence of the spiritual dimension on the physical realm, it would be more economically viable in the long term to ensure that adequate staffing levels are maintained so that staff has enough time to spend with patients to attend to their spiritual needs.