bluuebunny/crossref_metadata_2025_split huggingface dataset:
Domestication: an indigenous method in conserving plant diversity on farmlands in west Usambara Mountains, Tanzania
Authors: Msuya Tuli S. , Mndolwa Mathew A. , Kapinga Consolatha 
Published: April 2008

AbstractThe role of domestication in conserving indigenous plant diversity on farmlands was studied in West Usambara Mountains, Tanzania by structured, semi‐structured and unstructured interviews; participant observation; literature review and botanical identification in March 2006. There was high diversity of indigenous plant species on farmlands (73%) compared with exotics (27%). For the number of plants per species, a small proportion of indigenous plants (14%) were recorded compared with exotics (86%). Although the number of domesticated indigenous plant species has declined by 8% between 1998 and 2006, still 96% of the respondents practise domestication and they have domesticated at least one indigenous plant species each. Gender equity in domestication is lacking given that male‐headed households had domesticated significantly more plant species on farms than female‐headed households. Sustainability in domestication is questionable because of increasing number of exotic plants of very few species on farmlands, the phenomenon that encourages monoculture, thus threatening conservation of species diversity in inhabited areas. Suggestions for promoting domestication as an important indigenous method for conserving biodiversity are given, including the need for more number of studies to explore the biodiversity of other organisms associated with the domesticated indigenous plants.
Conservation of forage resources for increasing livestock production in traditional forage reserves in Tanzania
Authors: Mwilawa A. J. , Komwihangilo D. M. , Kusekwa M. L. 
Published: April 2008

AbstractTraditional reserved pastures namely ‘Olopololi/Alalili’ for Maasai, ‘Ngitili’ for Sukuma and ‘Milaga’ for Gogo have been in use among the pastoral and agropastoral communities for many years. These reserves provide dry season feed for ruminant livestock especially cattle, sheep and goats. Apart from the provision of forage materials, these reserves provide fuel wood, construction material and medicinal plants. These traditional forage conservation practices also contribute to soil conservation and forage species biodiversity. However, studies conducted in these traditional forage reserves at Tingatinga (Maasai), Makang’wa (Gogo) and in Mwamishali/Mwanyanhina (Sukuma) in Tanzania show limitations of the reserves especially, in providing adequate dry matter and proteins for both maintenance and production of livestock. Nevertheless, there are opportunities for improvement on these traditional practices through introduction of improved grasses, legumes and tree/shrub species as well as proper maintenance of the superior local species and cultivars.
Species communities and associations formed by the family Cyperaceae Juss. in some of Uganda’s wetlands
Authors: Ssegawa Paul , Kalema James 
Published: April 2008

AbstractThis study was conducted between August 2000 and April 2001 in ten wetlands areas of Uganda and these included Lakes Bisina, Nakuwa and Opeta, including the Doho Rice Scheme in the Lake Kyoga basin; Mabamba and Lutembe bays, Lake Nabugabo, Musambwa islands and Lutoboka peninsula in the Lake Victoria basin; and Nyamuriro swamp in Kigezi region. This study focused on Cyperaceae because of their known abundance in wet or damp areas. The aim was to assess the diversity and examine the communities and associations formed by sedges. Floristic data were collected using quadrats along transects. Cluster analysis was used to analyse for species associations. Principal components analysis was used to determine the descriptive species of the sites of the wetlands. A total of 113 taxa in 107 species belonging to 17 genera and classified into seven tribes were identified. The most rare species included Eleocharis dulcis (Burm. f.) Henschel and Cyperus iria L. Using cluster analysis the ten sites of the wetlands were classified into sedge assemblages that generally reflected ecoregional differences between the Lake Kyoga and Victoria basins. The three distinct clusters formed from cluster analysis also revealed species assemblages that represented associations of these sedges found in the sites of each cluster.
Untangling the complex issue of dissolved organic carbon uptake: a stable isotope approach
Authors: KAPLAN LOUIS A. , WIEGNER TRACY N. , NEWBOLD J. D. , OSTROM PEGGY H. , GANDHI HASAND 
Published: April 2008

Summary1. We estimated uptake of stream water dissolved organic carbon (DOC) through a whole‐stream addition of a 13C‐DOC tracer coupled with laboratory measurements of bioavailability of the tracer and stream water DOC.2. The tracer, a leachate of 13C‐labelled tree tissues, was added to the head waters of White Clay Creek, Pennsylvania, U.S.A., over a 2‐h period and followed 1.27 km downstream to generate mass transfer coefficients for DOC lability classes within the tracer.3. From the longitudinal 13C uptake curve, we resolved labile and semi‐labile DOC classes within the 13C‐DOC tracer comprising 82% and 18% of the tracer respectively.4. Plug‐flow laboratory bioreactors colonized and maintained with stream water were used to determine the concentration of stream water DOC fractions that had a similar lability to the labile and semi‐labile classes within the tracer and we assumed that stream water DOC and tracer DOC with comparable lability fractions in the bioreactors behaved similarly in the stream, i.e. they had the same mass transfer coefficients.5. A small fraction (8.6%) of the stream water DOC was labile, travelling 238 m downstream before being taken up. The remaining bioavailable stream water DOC was semi‐labile and transported 4.5 km downstream before being taken up. These uptake lengths suggest that the labile DOC is an energy source within a stream reach, while the semi‐labile DOC is exported out of the reach to larger rivers and the downstream estuary, where it may provide energy for marine microbial communities or simply be exported to the oceans.
Size‐independent age effects on reproductive effort in a small, short‐lived fish
Authors: TEDESCO PABLO A. , BENITO JOSEP , GARCÍA‐BERTHOU EMILI 
Published: April 2008

Summary1. Age‐related changes in reproductive effort have been predicted by theoretical models and observed in a wide range of organisms. However, for indeterminate growers such as fish, an allometric relationship linking gonad weight to body size is commonly observed. There is often a positive linear relationship when these variables are log‐transformed, which by implication reduces the influence of age on reproductive effort.2. Contrasting with this usual pattern, we report a nonlinear relationship between gonad weight and fish size (after log‐transformation) in mosquitofish (Gambusia holbrooki), clearly resulting from age changes. The declining rate of increase of gonad mass as a function of body size revealed a higher reproductive effort for younger individuals relative to size.3. This size‐independent age effect on reproductive effort was predicted based on previous studies of mosquitofish and is certainly related to their particular life‐history strategy, combining an early maturation and short lifespan with the physiological costs of reproduction and over‐wintering. Our findings probably apply to other small, short‐lived species with similar life history.
Echo‐sounding can discriminate between fish and macroinvertebrates in fresh water
Authors: JURVELIUS JUHA , KNUDSEN FRANK REIER , BALK HELGE , MARJOMÄKI TIMO J. , PELTONEN HEIKKI , TASKINEN JOUNI , TUOMAALA ANTTI , VILJANEN MARKKU 
Published: April 2008

Summary1. Acoustic scattering from fish and macroinvertebrates was studied in a boreal Finnish lake at three echosounder frequencies (38, 120 and 200 kHz). Split‐beam transducers with partly overlapping 7° beams were employed. Acoustic, fish and invertebrate sampling were undertaken simultaneously. Vertical gradients of temperature and oxygen concentration were measured during the exercise.2. At all frequencies, a narrow scattering layer coincided with the thermocline. At 38 kHz, fish were detected well with practically no reverberation from invertebrates while 200 kHz detected both fish and invertebrates.3. Minor differences in the magnitude of acoustic scattering from fish were found between frequencies and between depth layers, but scattering at different frequencies was correlated at all depths. Acoustic scattering and fish density indices from trawl catches, consisting mostly of smelt (Osmerus eperlanus) (97%) and vendace (Coregonus albula) (3%), were significantly correlated.4. Acoustic scattering from invertebrates increased with sound frequency. Correlation analysis suggested that the invertebrate scattering was mostly induced by Chaoborus flavicans. A low frequency is recommended for estimating fish abundance without bias from reverberation induced by invertebrate scattering. Although fish and invertebrates can also be successfully discriminated at a single frequency by thresholding and cross filtering, the combination of a low and a high frequency is a more robust tool for effective fish‐invertebrate discrimination.
Food quality influences habitat selection in Daphnia
Authors: REICHWALDT ELKE S. 
Published: April 2008

Summary1. The vertical distribution of Daphnia in stratified lakes strongly depends on the depth profiles of temperature and food resources. However, ecological requirements for these factors are slightly different for juvenile and adult Daphnia.2. Here, I investigated whether food quality influences the habitat selection of Daphnia pulicaria at night and whether the habitat selection of juvenile and adult D. pulicaria is different. Daphnia were allowed to choose their optimal habitat in large, stratified water columns (plankton towers, Plön) that held either the green alga Scenedesmus obliquus (high quality) in the cold hypolimnion (Hypo‐treatment) or S. obliquus in the warm epi‐ and cold hypolimnion (SCEN‐treatment) or the non‐toxic cyanobacterium Synechococcus elongatus (low quality) in the warm epilimnion and S. obliquus in the cold hypolimnion (SYN treatment).3. When food (S. obliquus) was present only in the hypolimnion (Hypo‐treatment), juveniles and adults distributed similarly in the water column and spent most of their time in the interface between the warm and the food rich layer.4. When food was present in the epilimnion and hypolimnion (SCEN‐ and SYN‐treatments), juvenile and adult D. pulicaria moved into the warm and now also food‐rich epilimnion, however, the magnitude of this shift depended on the food type and age class of Daphnia. Adult and juvenile D. pulicaria spent most of their time in the epilimnion when food there was of a high quality (S. obliquus; SCEN‐treatment). However, compared to the juveniles, adult Daphnia spent significantly more time in the colder hypolimnion when epilimnetic food was of a low quality (S. elongatus; SYN‐treament).5. Therefore, habitat selection of adult D. pulicaria was affected by food quality whereas the habitat selection of juveniles was not.6. Additional growth and reproduction experiments show that the food quality is likely to be responsible for the different habitat selection of juveniles and adults in the SYN‐treatment.7. In conclusion, my experiments show that D. pulicaria behaviourally reacts to the quality of its food source.
Population structure in the highly fragmented range of Tor douronensis (Cyprinidae) in Sarawak, Malaysia revealed by microsatellite DNA markers
Authors: NGUYEN THUY T. T. 
Published: April 2008

Summary1. Understanding the structure of threatened populations, particularly those that exist in degraded or fragmented habitats is crucial for their effective management and conservation. Recently developed methods of individual‐based analysis of genetic data provide an unprecedented opportunity to understand the relationships amongst fragmented populations.2. In the present study, population structure of an important cyprinid species (Tor douronensis), which is indigenous to Sarawak, Malaysia, is investigated as part of an ongoing conservation effort to restore threatened wild populations of the species. The population structure inferred using data from seven autosomal microsatellite loci was generally consistent with geography and habitat fragmentation.3. The results indicate that there are two well‐defined clusters of T. douronensis in Sarawak, namely the ‘northeastern’ and the ‘southwestern’ clusters. In addition, a further subdivision was observed in each of the clusters distributed between river systems. Low levels of gene flow were also observed and migrants between habitat fragments were identified, possibly resulting from human‐mediated translocations.4. Implications of the findings for management and conservation of T. douronensis are discussed.
Efficacy of algal metrics for assessing nutrient and organic enrichment in flowing waters
Authors: PORTER STEPHEN D. , MUELLER DAVID K. , SPAHR NORMAN E. , MUNN MARK D. , DUBROVSKY NEIL M. 
Published: April 2008

Summary1. Algal‐community metrics were calculated for periphyton samples collected from 976 streams and rivers by the U.S. Geological Survey’s National Water‐Quality Assessment (NAWQA) Programme during 1993–2001 to evaluate national and regional relations with water chemistry and to compare whether algal‐metric values differ significantly among undeveloped and developed land‐use classifications.2. Algal metrics with significant positive correlations with nutrient concentrations included indicators of trophic condition, organic enrichment, salinity, motility and taxa richness. The relative abundance of nitrogen‐fixing algae was negatively correlated with nitrogen concentrations, and the abundance of diatom species associated with high dissolved oxygen concentrations was negatively correlated with both nitrogen and phosphorus concentrations. Median algal‐metric values and nutrient concentrations were significantly lower at undeveloped sites than those draining agricultural or urban catchments.3. Total algal biovolume did not differ significantly among major river catchments or land‐use classifications, and was only weakly correlated with nitrate (positive) and suspended‐sediment (negative) concentrations. Estimates of periphyton chlorophyll a indicated an oligotrophic–mesotrophic boundary of about 21 mg m−2 and a mesotrophic–eutrophic boundary of about 55 mg m−2 based on upper and lower quartiles of the biovolume data distribution.4. Although algal species tolerance to nutrient and organic enrichment is well documented, additional taxonomic and autecological research on sensitive, endemic algal species would further enhance water‐quality assessments.
Horizontal/oblique root fractures in the palatal root of maxillary molars with associated periodontal destruction: case reports
Authors: Lin C. C. , Tsai Y. L. , Li U. M. , Chang Y. C. , Lin C. P. , Jeng J. H. 
Published: April 2008

AbstractAim  To report two cases of palatal root fracture in maxillary molars that were successfully managed in the short term by root canal treatment and root amputation.Summary  In the first case, a 48‐year‐old woman with bony destruction and a deep periodontal pocket on the palatal root of tooth 26 (FDI) underwent root canal treatment. Bleeding into the palatal canal and radiolucent lines over the root suggested a fracture. Further evidence was provided by an electronic apex locator. Subsequent surgery confirmed the presence of a horizontal root fracture and the fractured root was removed. In the second case, a 75‐year‐old woman presented with pain from the left posterior teeth. Clinical examination revealed an oblique root fracture of tooth 27 palatal roots with abscess formation and a deep periodontal pocket. Palatal root amputation and odontoplasty were performed. This was followed by root canal treatment. Both teeth were preserved in the short term and early healing of these two cases was uneventful.Key learning points

Horizontal/oblique root fracture of the palatal root in molars is rare.
A combination of periodontal and root canal treatment and palatal root amputation may allow short‐term preservation of functional teeth.
Preparation and evaluation of pizza cheese made from blend of vetch–bovine milk
Authors: Salim‐ur‐Rehman  , Piggott John R. , Ahmad Muhammad Mushtaq , Hussain Sarfraz , Ahmad Nasir , Owusu‐Darko Patricia 
Published: April 2008

SummaryThe objective of the study was to develop vetch–bovine milk (VBM) pizza cheese low in animal fat and its acceptability was determined through physico‐chemical, functional and sensory evaluations. Vetch (Lathyrus sativus) was detoxified by steeping in double its quantity of water for 8 h at 70 °C, changing the water seven times, draining and sun drying. Dried vetch was then treated with water at pH 4.0 at 90 °C for 60 min to deplete the beany flavour, then dried and milled into fine flour with Quadrumate Senior mill. The seed coat was separated as one of the mill fractions. Four types of VBM blends were prepared from vetch flour and bovine skimmed milk powder and were used to prepare cheese using 2.5% lactic acid bacterial culture of Streptococcus thermophillus and Streptococcus bulgaricus and rennet (0.15 mL L−1, 1:40 ratio with water). The cheese was stored at 4 °C for 14 days and used as topping over the pizza shell. Physico‐chemical analyses, such as moisture, total solids, lactose, ash, fat, titratable acidity and pH, and sensory evaluations of both cheese and pizza were carried out at 0‐, 7‐ and 14‐day intervals. The stretchability and meltability of cheese increased significantly (P < 0.05) during storage. Commercial Mozzarella cheese was taken as a control. The results of this study suggested that VBM blend at the ratio of 12.5:87.5 (vetch flour:bovine milk powder) could be utilised to prepare a cheese of desirable characteristics for pizza topping.
Effect of pH and addition of corn oil on the properties of whey protein isolate‐based films using response surface methodology
Authors: Wang Lizhe , Liu Li , Holmes Justin , Huang Jian , Kerry John F. , Kerry Joe P. 
Published: April 2008

SummaryResponse surface methodology (RSM) was used to investigate pH and corn oil (CO) effects on the properties of films formed from whey protein isolate (WPI). Test films were evaluated for tensile strength (TS), puncture strength (PT), percentage elongation at break point (E), water vapour permeability (WVP) and oxygen permeability (OP). TS of WPI films increased with increasing pH, while addition of CO produced no trend. However, when WPI solution pH increased >10.0, film TS generally decreased with CO addition (>11%). E values increased dramatically with increasing levels of CO when pH for WPI solutions were >8.5. However, pH had no effect on E values. WPI solutions possessing high pH values (maximum pH value of 10.62) produced WPI films with the highest PT values. WVP had a quadratic relationship with pH and CO addition. OP had an inversely linear relationship with increasing pH (6.5–10.5) and a quadratic relationship with CO addition. Optimal pH (9.88) and CO level (2.93%), determined from physical test film data, were predicted by RSM.
Carbohydrate‐based fat replacers in the modification of the rheological, textural and sensory quality of yoghurt: comparative study of the utilisation of barley beta‐glucan, guar gum and inulin
Authors: Brennan Charles S. , Tudorica Carmen M. 
Published: April 2008

SummaryBarley beta‐glucan, partially hydrolysed guar gum and inulin were used in the processing of low‐fat yoghurts. The possible beneficial effects of carbohydrate fat replacers on the rheological, textural and sensory quality of low‐fat yoghurt‐based products were determined. Comparisons were made between the sample yoghurts made from a low‐fat milk base, and full‐fat and low‐fat yoghurt controls. The inclusion of the carbohydrate components reduced product syneresis and improved the texture and rheological properties of the low‐fat‐based products so that their quality characteristics were similar to yoghurt made with full‐fat milk. Both the type and also the amount of carbohydrate component altered product characteristics. Beta‐glucan addition at low level (0.5%) was effective in improving serum retention of the yoghurt and its viscoelastic nature (G′, G′ and tan δ). In contrast, higher levels (above 2%) of inulin and guar gum were needed to exert significant improvements in the textural characteristics of yoghurt. Sensory analysis conducted on the samples illustrated that the inclusion of carbohydrate‐based fat replacers could be successfully utilised to mimic full‐fat products.
Moisture sorption isotherm and xerophilic moulds associated with dried cocoyam chips in storage in Nigeria
Authors: Ugwuanyi J. Obeta 
Published: April 2008

SummaryExtended storage of cocoyams (Colocasia antiquorum and Colocasia esculenta) is achieved in parts of Nigeria by processing them into smoked and dried chips. In this study, cocoyam chips were collected from parts of Nigeria at the end of drying, at various periods of storage and from markets, and analysed for moisture content, moisture sorption characteristics and xerophilic moulds. Moisture content of chips ranged from 7.07 ± 1.1% for freshly dried samples to 16 ± 2.2% for samples stored up to 8 months. Six mould species from four groups of the genus Aspergillus (including five xerophiles) identified as Aspergillus fumigatus, Eurotium repens, Eurotium amstelodami, Eurotium chevalieri and Aspergillus flavus and Aspergillus niger and Mucor sp. were isolated. The variety of moulds increased with storage and moisture content of samples. Moisture sorption in dried chips showed type II sigmoidal behaviour. Wood smoke significantly protected chips from mould colonization, but in cooperation with reduced water activity. Simple and inexpensive storage of freshly dried samples in airtight bags led to prolonged storage of up to 14 months without deterioration.
Effects of differences in diet and seasonal changes on the fatty acid composition in fillets from farmed and wild sea bream (Sparus aurata L.) and sea bass (Dicentrarchus labrax L.)
Authors: Yildiz Mustafa , Şener Erdal , Timur Metin 
Published: April 2008

SummaryThe effects of dietary fatty acids and seasonal variation on the fatty acid profiles of farmed and wild sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax) were determined by analysis of their fillets. Farmed sea bream and sea bass were fed on the same commercial feeds all year. Fatty acid profiles in the fillets reflected the fatty acid profiles of the commercial feeds. The predominant fatty acids in the trial feeds, fillets of farmed and wild sea bream and sea bass were 16:0, 18:1n‐9, 18:2n‐6, 20:5n‐3 and 22:6n‐3. The fatty acid profiles in the fillets of farmed sea bream and sea bass did not differ (P > 0.05) except in the winter season compared with those of their wild counterparts. However, the content of eicosapentaenoic acid (20:5n‐3), docosahexaenoic acid (22:6n‐3) in the fillets of the farmed and wild sea bass were significantly (P < 0.05) higher than the farmed and wild sea bream. The wild sea bream had significantly (P < 0.05) higher total saturated fatty acid and monounsaturated fatty acid (MUFA) levels, and lower total n‐6 and n‐3 polyunsaturated fatty acid (PUFA) levels in winter than in the summer and spring seasons. Similarly, in the fillets of wild sea bass, total n‐3 PUFA levels were significantly (P < 0.05) lower, and the MUFA levels were higher in winter than in the other seasons. These results indicate that the farmed fish fillets were good sources of n‐3 PUFA in each of the three seasons. However, wild fish were good sources of n‐3 PUFA in the spring and summer.