bluuebunny/crossref_metadata_2025_split huggingface dataset:
Changes in population characteristics and diet of Nile tilapia Oreochromis niloticus (L.) from Nyanza Gulf of Lake Victoria, Kenya: what are the management options?
Authors: Njiru M. , Okeyo-Owuor J. B. , Muchiri M. , Cowx I. G. , van der Knaap M. 
Published: November 2007

Length frequency data collected from 1998 to 2001 from commercial landings was used to estimate asymptotic length (L∞), growth coefficient (K), mortality (Z, F, M), growth performance index (φ ′) and exploitation rate (E) of Oreochromis niloticus from the Nyanza Gulf of Lake Victoria, Kenya. Studies on the diet of O. niloticus collected by demersal trawl and seining between 1998 and 2000 were also conducted.
Length frequency data were analyzed using the FISAT software (an FAO-ICLARM Stock Assessment Tool package). The L∞ had a mean value (± S.D) of 58.78 ± 2.42 cm TL, K of 0.59 ± 0.05 yr− 1, Z of 2.16 ± 0.40 yr− 1, M of 1.00 ± 0.06 yr−1, F of 1.12 ± 0.34 yr−1, E of 0.48 ± 0.11 and φ ′ of 3.31 ± 0.04. Length at first entry into the fishery (L50) was observed at 26.18 ± 12.50 cm TL. Recruitment occurred throughout the year, with two peaks corresponding with the rainy seasons.
A comparison with previous studies in the gulf indicates that O. niloticus is now caught at a smaller mean size, whereas K, Z, and M have increased. Fish appeared to become sexually mature at a smaller size.
Nile tilapia originally known to be herbivorous, feeding mostly on algae, has diversified its diet to include insects, fish, algae and plant materials, all being important food items. The changes in population characteristics and diet of O. niloticus are discussed in context of changes occurring in the lake and its surroundings.
Prenatal administration of vitamin A alters pulmonary and plasma levels of vascular endothelial growth factor in the developing mouse
Authors: Pinto Maria de Lurdes , Rodrigues Paula , Coelho Ana Cláudia , Pires Maria dos Anjos , Santos Dario Loureiro dos , Gonçalves Carlos , Bairos Vasco António 
Published: November 2007

SummaryVitamin A and the retinoids play a unique role in mammalian embryonic and foetal development and are essential for both cellular differentiation and the establishment of normal morphogenesis. Vascular endothelial growth factor (VEGF) is a known potent mitogenic factor that plays a key role in lung development and function maintenance. In order to contribute to a better knowledge of the modulating effects of vitamin A in lung development, we investigated the effects of the antenatal administration of vitamin A on VEGF expression in lungs and plasma from foetuses and neonates. Pregnant mice were subjected to subcutaneous administration of vitamin A on the 12th gestational day. The lungs and plasma from foetuses and neonates were collected daily from the 15th gestational day till the day of birth. Our results show that vitamin A modulates VEGF concentrations both in lungs and plasma. Statistically significant differences were observed at gestational days 15 (P = 0.004 for lungs; P < 0.0001 for plasma), 16 (P < 0.0001 for lungs and plasma) and 18 (P < 0.0001 for lungs; P < 0.05 for plasma). Vitamin A tends to increase the expression of this factor in the lung, particularly during the critical period of perinatal adaptation to postnatal life. These effects seem to be spatial and temporally regulated, and point out to the important role of vitamin A during lung development.
Staffing adequacy, supervisory support and quality of care in long‐term care settings: staff perceptions
Authors: Räikkönen Outi , Perälä Marja‐Leena , Kahanpää Anja 
Published: November 2007

AbstractTitle.  Staffing adequacy, supervisory support and quality of care in long‐term care settings: staff perceptions Aim.  This paper is a report of a study to explore relationships between perceived care quality, self‐assessed professional skills, and the perceptions of the quality‐related factors.Background.  The work in long‐term care is more demanding than in the past. The quality of care is strongly related to the well‐being and job satisfaction of staff. Those emerge in part through a perception of resources allocated to caring and also through a perception of the quality achieved.Method.  Data were collected in Finland in 2002 using a questionnaire sent to the nursing staff working in 112 wards in 40 long‐term care institutions monitoring their care with the Resident Assessment Instrument System. Institutions were invited to participate the survey. The response rate was 70·2% (n = 1262). The respondents represented 3·8% of nursing personnel working in long‐term care institutions.Findings.  Staff members who perceived staffing levels as inadequate and supervisory support as insufficient had lower perceptions of their own professional skills and the quality of care. Perceptions of empowering support behaviour were more strongly associated to self‐assessed skills and to perceived care quality than perceptions of skills‐oriented support activities.Staff members with short professional training, older staff members and staff members with long work experience in the unit had lower perceptions of their professional skills than other groups.Conclusion.  The perception of adequate staffing and of sufficient supervisory support, especially empowering support increases the probability of perceiving the care quality as good. If supervisors concern themselves with staff members’ perceptions, they can better identify the staffing needs and also the support needs of personnel.
Buoyancy‐driven deformation and contemporary tectonic stress in the lithosphere beneath Central Italy
Authors: Aoudia A. , Ismail‐Zadeh A. T. , Romanelli F. 
Published: November 2007

AbstractWe studied the continental deformation and modelled the contemporary flow and stress distribution in the lithosphere beneath Central Italy. We made use of a revisited crust and uppermost mantle Earth structure that supports delamination processes. The model behaviour is primarily determined by the thick high density lithospheric root to the east and the low‐viscosity shallow mantle wedge to the west. The rate of the modeled crustal motion is in agreement with GPS data and the pattern of lithospheric flow explains the heat flux, the regional geology and provides a new background for the genesis and age of the recent Tuscan magmatism. The modelled stress in the lithosphere is spatially correlated with the prevailing stress field and the gravitational potential energy patterns and shows that buoyancy forces, solely, can explain the coexisting regional contraction and extension and the unusual sub‐crustal seismicity.
Female coloration indicates female reproductive capacity in blue tits
Authors: DOUTRELANT C. , GRÉGOIRE A. , GRNAC N. , GOMEZ D. , LAMBRECHTS M. M. , PERRET P. 
Published: November 2007

AbstractIt is poorly understood whether female morphological and behavioural traits can be used as ‘signals’. In particular, experimental tests of the hypothesis that female ornaments reflect quality are scarce. Here, we experimentally examine whether female plumage coloration might signal maternal quality in the blue tit, Cyanistes caeruleus by forcing half of the females breeding in our population to produce a replacement clutch. Using statistical models that controlled for the effects of male coloration, and the effects of age and condition of both parents, we found that carotenoid‐based female coloration was positively linked to key proxies of bird lifetime reproductive success: clutch size, fledgling success and recruitment. Importantly, the relationships between maternal yellow carotenoid coloration and both clutch size and recruitment were stronger in the experimental group than in the control group, indicating that breeding females with higher values of yellow coloration were better able to handle the cost of producing a second clutch. Finally, UV‐blue female coloration was positively linked to female survival and marginally linked to laying date. Taken together, these results show for the first time in a natural population that female coloration can indicate individual and maternal quality under natural and adverse reproductive conditions. They highlight the potential for the evolution of female ornamental traits through sexual selection.
Coevolution and the adaptive value of autumn tree colours: colour preference and growth rates of a southern beech aphid
Authors: RAMÍREZ C. C. , LAVANDERO B. , ARCHETTI M. 
Published: November 2007

AbstractThe evolutionary explanation for the change in leaf colour during autumn is still debated. Autumn colours could be a signal of defensive commitment towards insects (coevolution) or an adaptation against physical damage because of light at low temperatures (photoprotection). These two hypotheses have different predictions: (1) under the coevolution hypothesis, insects should not prefer red leaves in autumn and grow better in spring on trees with green autumn leaves; and (2) under the photoprotection hypothesis, insects should prefer and grow better on trees with red leaves because they provide better nutrition. Studying colour preference in autumn and growth rates in spring of a southern beech aphid species (Neuquenaphis staryi) on Nothofagus alessandrii, we found preference for green leaves in autumn but no differential performance of aphids in spring. We suggest that aphid preference for green might have evolved to exploit better their host during the autumn rather than to improve their performance in spring.
Sibutramine‐associated adverse effects: a practical guide for its safe use
Authors: Florentin M. , Liberopoulos E. N. , Elisaf M. S. 
Published: November 2007

SummaryObesity is a multifactorial chronic disorder which comprises a serious health problem nowadays. The effective management of obesity is difficult in contemporary societies where abundance of hypercaloric food and sedentary lifestyle is the rule. Apart from lifestyle interventions, which include diet, exercise and behavioural treatment, weight‐loss medications can also be used for the management of obesity. Sibutramine, a selective monoamine reuptake inhibitor, is a drug with established efficacy in sustained weight reduction and an overall favourable safety profile. However, its action on the sympathetic nervous system has linked sibutramine to blood pressure and heart rate elevations. These potentially adverse effects as well as other sibutramine‐associated side effects and their possible underlying mechanisms are reviewed in the present article. Compelling evidence from the majority of data in the literature shows that sibutramine can be effectively used in conjunction with caloric restriction and exercise in obese patients. Hypertension, if adequately treated and frequently monitored, is not an absolute contraindication for the prescription of sibutramine.
RELATIVISM, COMMENSURABILITY AND TRANSLATABILITY
Authors: Glock Hans‐Johann 
Published: November 2007

AbstractThis paper discusses conceptual relativism. The main focus is on the contrasting ideas of Wittgenstein and Davidson, with Quine, Kuhn, Feyerabend and Hacker in supporting roles. I distinguish conceptual from alethic and ontological relativism, defend a distinction between conceptual scheme and empirical content, and reject the Davidsonian argument against the possibility of alternative conceptual schemes: there can be conceptual diversity without failure of translation, and failure of translation is not necessarily incompatible with recognizing a practice as linguistic. Conceptual relativism may be untenable, but not for the hermeneutic reasons espoused by Davidson.
Reintegration Support for Young Ex‐Combatants: A Right or a Privilege?
Authors: Peters Krijn 
Published: November 2007

ABSTRACTUnder‐age and youthful combatants are the major participants in contemporary African conflicts and, therefore, the largest group to be disarmed, demobilized and reintegrated when peace agreements are signed. Programmes to support this process, so‐called disarmament, demobilization and reintegration (DDR) programmes, usually have two main objectives: 1) to reduce security risks; and 2) make ex‐combatants less dependent upon their home communities once returned. However, badly designed or implemented DDR programmes can jeopardize a country's fragile peace and rehabilitation process.This article uses the Sierra Leone case to explore the efficacy of DDR programmes. It questions whether the reintegration options offered to the demobilized ex‐combatants were appropriate to the context. In a country where more than 70 per cent of the population depends on (semi‐)subsistence agriculture, the most popular reintegration package among the young ex‐combatants was vocational training ‐ only 15 per cent of the ex‐combatants chose the “agricultural package”. The article questions whether young ex‐combatants are simply disinterested in farming, and, if so, whether vocational skills training programmes offer realistic alternative livelihood opportunities.This article argues that most ex‐combatants have not been able to achieve sustainable livelihoods skills due to failures in DDR programmes. The existence of a large reservoir of marginalized, foot‐loose youth has been widely acknowledged as one of the root causes of the conflict in Sierra Leone. There is clear evidence that one result of the poor DDR design and implementation is that this reservoir has not been sufficiently drained in Sierra Leone.
Building capacity in ageing research: Implications from a survey of emerging researchers in Australia
Authors: Bartlett Helen , Underwood Mair , Peach Linda 
Published: November 2007

Objective:  The National Emerging Researchers in Ageing Study (NERAS) set out to inform capacity‐building efforts in ageing research. Its purpose was to identify the interest, attitudes and motives of PhD students to enter the field and factors influencing intention to remain. Method:  A web‐based survey was sent to 267 PhD students in ageing. It assessed attitudes towards older people and the importance of a variety of factors influencing students’ interest and decision to engage in ageing research. Results:  The response rate was 60% (n = 161). Positive attitudes, interest in ageing issues and concern for older people were key motivating factors to work or study in the field. Supervisors in ageing and initial interest in the field were key predictors of intention to remain in the field. Conclusions:  NERAS is the first national study of emerging researchers in ageing and it provides important new knowledge with implications for capacity‐building efforts.
Effects of Cadmium on Polar Lipid Composition and Unsaturation in Maize (Zea mays) in Hydroponic Culture
Authors: Chaffai Radhouane , Seybou Tinni Nouhou , Marzouk Brahim , El Ferjani Ezzedine 
Published: November 2007

Abstract This study aimed to evaluate the effect of Cd exposure (100 μmol/L) on polar lipid composition, and to examine the level of fatty acid unsaturation in maize (Zea mays L.). In roots, the level of 16:0 and monounsaturated fatty acids (16:1 + 18:1) decreased in phosphatidylcholine (PC) and phosphatidylethanolamine (PE). In contrast, the proportion of unsaturated 18‐C fatty acid species showed an opposite response to Cd. The content, on the other hand, of PC, PE, digalactosyldiacylglycerol (DGDG), and steryl lipids increased in roots (2.9‐, 1.6‐, 5.3‐, and 1.7‐fold increase, respectively). These results suggest that a more unsaturated fatty acid composition than found in control plants with a concomitant increase in polar lipids may favor seedling growth during Cd exposure. However, the observed increase in the steryl lipid (SL) : phospholipid (PL) ratio (twofold), the decrease in monogalactosyldiacylglycerol (MGDG) : DGDG ratio, as well as the induction of lipid peroxidation in roots may represent symptoms of membrane injury. In shoots, the unsaturation level was markedly decreased in PC and phosphatidylglycerol (PG) after Cd exposure, but showed a significant increase in sulfoquinovosyldiacylglycerol (SQDG), MGDG and DGDG. The content of PG and MGDG was decreased by about 65%, while PC accumulated to higher levels (4.4‐fold increase). Taken together, these changes in the polar lipid unsaturation and composition are likely to be due to alterations in the glycerolipid pathway. These results also support the idea that the increase in overall unsaturation plays some role in enabling the plant to withstand the metal exposure.
Novel Combination of Atomic Force Microscopy and Epifluorescence Microscopy for Visualization of Leaching Bacteria on Pyrite
Authors: Mangold Stefanie , Harneit Kerstin , Rohwerder Thore , Claus Günter , Sand Wolfgang 
Published: November 2007

ABSTRACT

Bioleaching of metal sulfides is an interfacial process comprising the interactions of attached bacterial cells and bacterial extracellular polymeric substances with the surface of a mineral sulfide. Such processes and the associated biofilms can be investigated at high spatial resolution using atomic force microscopy (AFM). Therefore, we visualized biofilms of the meso-acidophilic leaching bacterium
Acidithiobacillus ferrooxidans
strain A2 on the metal sulfide pyrite with a newly developed combination of AFM with epifluorescence microscopy (EFM). This novel system allowed the imaging of the same sample location with both instruments. The pyrite sample, as fixed on a shuttle stage, was transferred between AFM and EFM devices. By staining the bacterial DNA with a specific fluorescence dye, bacterial cells were labeled and could easily be distinguished from other topographic features occurring in the AFM image. AFM scanning in liquid caused deformation and detachment of cells, but scanning in air had no effect on cell integrity. In summary, we successfully demonstrate that the new microscopic system was applicable for visualizing bioleaching samples. Moreover, the combination of AFM and EFM in general seems to be a powerful tool for investigations of biofilms on opaque materials and will help to advance our knowledge of biological interfacial processes. In principle, the shuttle stage can be transferred to additional instruments, and combinations of AFM and EFM with other surface-analyzing devices can be proposed.
The development and implementation of MAID: a knowledge based support system for use in control system design
Authors: Boyle J.-M. , Pang G.K.H. , MaeFarlane A.G.J. 
Published: November 2007

The development of a Knowledge Based System (KBS) that can assist a designer in performing advanced multivariable control system design is the central theme of this paper. It starts by describing the role KBSs can play as designer's assistants. Then it is argued that the goal of developing a KBS can lead to a detailed analysis, and hence reformulation, of the essential design theory. The main body of the paper gives a description of how complex design concepts and strategies can be described and organised into a knowledge base. As the title suggests, this paper focuses on the actual implementation of a prototype KBS for control design: MAID. An example of a design session is included.
A low-cost software correlator based on a new polarity correlation algorithm
Authors: Harba M.I.A. , Said S.M. 
Published: November 2007

A new software correlator for polarity correlation estimation is presented. This correlator achieves a high sampling rate by block sampling, which makes it possible to store the signal samples in the individual bits of the microprocessor memory locations, so reducing the overall memory requirements of the correlator. The computational efficiency of the algorithm is derived from the ability of microprocessors to process complete bytes of data simultaneously. This correlator is implemented on a standard 8-bit microprocessor. The algorithm used makes this correlator superior to other software correlators, including the zero-crossing correlator. The latter is, perhaps, the fastest software correlator available. It will be shown that for practical values of sampling rates, the new correlator is more economic in terms of signal storage, faster in terms of time of execution and has an operational bandwidth an order of magnitude higher than that of the zero-crossing correlator.
Dynamical systems theory applied to management accounting: chaos in cost behaviour in a standard costing system setting
Authors: Tse N.S.F. , Robb F.F. 
Published: November 2007

This Research Report draws the attention of control engineers to some of the results obtained from the application of chaos theory to modelling complex behaviour, The example chosen is a typical management accounting system in a manufacturing firm, and the model includes not only the formal control devices, but also the responses af the human operators, the managers, to the variance signals from that system. Management accounting has become an eclectic discipline and so over time it has called upon a wide variety of methodologies to help to address its problems. It has, perhaps reluctantly, accepted the notion that statistical analysis and the assessment of probabilities can overcome, in part at least, the ambiguity of many managerial situations. It would be expected to be very eager to consider ways and means of reducing reliance on such methods and of increasing the explanaiory power of some of the tools already at its disposal within its own core discipline; for example, the setting of standards for budgetary control. This paper reports recent research into the application of 'Dynamical Systems Theory'as a means of explaining apparently random cost behaviour in a standard cost context. It suggests that attention should be directed to the effects of different standard setting policies on the stability of the behaviour of managerial control systems.
Sonority and markedness among onset clusters in the interlanguage of ESL learners
Authors: Eckman Fred R. , Iverson Gregory K. 
Published: November 2007

This paper is intended as a contribution to an evergrowing body of literature on the role played by principles and parameters of Universal Grammar in second-language acquisition theory. A recent paper by Broselow and Finer (1991) proposes that markedness as defined in terms of the multivalued Minimal Sonority Distance (MSD) parameter is definitive in their subjects' knowledge of certain consonant clusters in syllable onsets. This parameter provides for the characterization of the various types of consonant clusters allowed in the onsets of syllables in different languages. The object of Broselow and Finer's study was to determine whether L2 learners find clusters which are relatively more marked according to the MSD parameter to be more difficult to learn than cluster types which are relatively less marked. The present paper, however, argues that it is typological markedness (Hawkins, 1987) rather than sonority distance per se which better explains L2 learners' knowledge of English clusters in syllable onsets. In line with Clements' (1990) comprehensive investigation of sonority relations within the syllable, this paper argues that markedness alone suffices to account for the observed interlanguage patterns. Using Clements' principles, which themselves actually follow from the overall theory of markedness, the interlanguage obstruent results reported by Broselow and Finer fall out automatically.