bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluating the performance of a soil compaction sensor
Authors: Sharifi A. , Godwin R. J. , O'Dogherty M. J. , Dresser M. L. 
Published: May 2007

AbstractOne of the most significant soil parameters affecting root growth is soil compaction. It is therefore important to be able to determine the presence of compacted layers, their depth, thickness and spatial location without the necessity of digging a large number of holes in the field with either a spade or backhoe. Previous investigations have identified soil compaction by different methods such as: using ground penetrating radar, acoustic systems, vertical and horizontal penetrometers and instrumented wings mounted on the faces of tines. Linking the output from these sensors to global positioning systems would give an indication of the spatial patent variation. The aim of this study was to evaluate the performance of a soil compaction profile sensor in both controlled laboratory and field conditions. The sensor consisted of a series of instrumented flaps; a flap is defined as the sensing element which comprises one half of a pointed leading edge to the leg of a tine to which strain gauges are placed on the rear face of the flap. Studies measured the effect of compaction on the changes in the soil resistance acting upon a flap face in a soil bin laboratory and under field conditions. The results indicated that the sensor was sensitive to differences in soil strength at different depths in soils. A technique was developed to identify the soil compaction resulting from different tyre inflation pressures and loads. The soil compaction profile sensor was tested on a number of fields in south‐eastern England to determine the changes in soil strength below the wheelings of a pea harvester operating at different tyre inflation pressures.
Decomposing the Value of Agricultural Multifunctionality: Combining Contingent Valuation and the Analytical Hierarchy Process
Authors: Kallas Zein , Gómez‐Limón José A. , Hurlé Jesús Barreiro 
Published: May 2007

AbstractAgricultural multifunctionality is the recognition of the joint exercise of economic, environmental and social functions by this sector. Nevertheless, not all these contributions to society are valued in markets, moreover a large share of them are public goods. For this reason, in order to make this concept of multifunctionality operative for the design of public policies, it is necessary to estimate the social demand of such functions. The objective of this article was to implement an empirical application along these lines. For this purpose, the agricultural system of cereal steppes in Tierra de Campos in Spain is taken as a case study. The economic valuation technique used relies on a combined implementation of contingent valuation and the analytical hierarchy process. The results obtained demonstrate the existence of a significant demand for the different attributes included in the multifunctionality concept, although this demand is heterogeneous and is based on the socioeconomic characteristics of individual persons.
Equivalence of Input Quotas and Input Charges under Asymmetric Information in Agri‐environmental Schemes
Authors: Ozanne Adam , White Ben 
Published: May 2007

AbstractA model of adverse selection and moral hazard in agri‐environmental schemes is developed based on the input quota mechanism of Moxey et al. (Journal of Agricultural Economics, Vol. 50, (1999) pp. 187–202) and Ozanne et al. (European Review of Agricultural Economics, Vol. 28, (2001) pp. 329–347), rather than the input charge mechanism of White (Journal of Agricultural Economics, Vol. 53, (2002) pp. 353–360), but the variable fine of the latter rather than the fixed fine assumed by Ozanne et al. (European Journal of Agricultural Economics, Vol. 28, (2001) pp. 329–347) is used. Incentive‐compatible contracts, including the optimal probabilities of detection (and, therefore, monitoring frequencies and costs) for more and less efficient farmers, are identified. It is shown that the input charge and input quota approaches lead to identical outcomes – in terms of abatement levels, compensation payments, monitoring costs and probabilities of detection – confirming the equivalence of input quotas and input charges under asymmetric information. It is also shown that the optimal contracts are independent of the risk preferences of farmers with regard to being caught cheating.
Assessing the Potential Impact of Avian Influenza on Poultry in West Africa: A Spatial Equilibrium Analysis
Authors: You Liangzhi , Diao Xinshen 
Published: May 2007

AbstractWe analyse the potential economic impacts of avian influenza (AI) in Nigeria, using a spatial equilibrium simulation model. Depending on the size of the affected areas, the direct impact of the spread of AI along the two major migratory bird flyways would be a loss of about 4% of national chicken production. However, the indirect effect – consumers’ reluctance to consume poultry if AI is detected, causing a decline in chicken prices – is generally larger than the direct effect in our simulation. We estimate that Nigerian chicken production would fall by 21% and chicken farmers would lose US$250 million of revenue if the worst‐case scenario occurs. The negative impact would be unevenly distributed in the country, and some states and districts would be seriously affected. The study shows that, while most attention has focused on preventing a global influenza pandemic, preventive measures are also needed at the national, regional and local levels, because AI could potentially have a major negative impact on the poultry industry and the livelihood of smallholder farmers in many regions in West Africa.
Spanish Demand for Food Away from Home: Analysis of Panel Data
Authors: Angulo Ana M. , Gil José M. , Mur Jesús 
Published: May 2007

AbstractWe analyse the Spanish demand for food away from home (FAFH). A panel dataset is built and appropriate techniques for estimating limited dependent variable models are applied. Results indicate that where there are zero expenditures, these are largely due to infrequency of purchase rather than to abstention, or for economic reasons. Furthermore, important differences appear among households. Households whose head is a highly educated person, male, young and living on a salary in a large town is more likely to purchase FAFH. FAFH expenditure responses to an increase in total per capita expenditure are markedly different depending on the age of the household's head, their employment status and also the size of the resident's town. The lowest elasticity is shown by single‐person households, between 36 and 55 years old, employed and living in large towns, for whom FAFH has become a necessity. On the other hand, FAFH remains a luxury for unemployed couples with one or two children.
Relationships between Technical Efficiency and Financial Management for Czech Republic Farms
Authors: Davidova Sophia , Latruffe Laure 
Published: May 2007

AbstractThis paper provides the first analysis of the relationship between farm financial structure and technical efficiency in Central and Eastern European farming during the transition to a market economy. First, technical efficiency scores for a sample of Czech farms are computed with data envelopment analysis, accounting for sampling variability by using the Simar and Wilson bootstrapping procedure. The confidence intervals show that corporate livestock farms are the most homogenous in terms of technical efficiency. Second, a Tobit model is applied for the investigation of factors, including financial considerations, which influence the variation in technical efficiency. The potential endogeneity of the financial variables in the explanation of efficiency is examined, following Smith and Blundell. The Amemiya estimator is used for those cases which are revealed as endogenous. The analysis indicates substantial differences in the way in which the different management structures are treated by lenders. De novo, individual farms are subject to stringent evaluation of their loan applications, which is not the case for the successors of the former collective and state farms.
Will the TRIPS Agreement Foster Appropriate Biotechnologies for Developing Countries?
Authors: Gaisford James D. , Hobbs Jill E. , Kerr William A. 
Published: May 2007

AbstractWhile almost all of the investment in agricultural biotechnology to date has been in temperate crops suitable for developed countries, developing countries are the greatest potential beneficiaries of this major technological advance. To realise this potential requires investment in crops appropriate to climatic and agronomic conditions in developing countries. Protection of intellectual property rights is a necessary condition for the private sector to invest in appropriate biotechnologies. This paper develops a game theoretic model of a bioscience firm that adapts a new technology to a range of agronomic conditions in response to the enforcement of intellectual property rights in a developed and a developing country. Over a range of potential penalties, low levels of enforcement by the developing country remain endemic despite the desire to have the bioscience firm adapt the biotechnology to its local conditions. In particular, the trade penalties contained in the Agreement on Trade‐Related Aspects of Intellectual Property Rights are likely to be ineffective. The developing country might increase enforcement if the developed country was more aggressive in liberalising agriculture trade because there would be greater symmetry in the benefits of the technology.
Meta‐Analysis, Meta‐Regression, and Meta‐Physics
Authors: Kostis John B. 
Published: May 2007

Παντɛςανθρωποιτοv ɛιδɛναιορɛγονταιφvσɛι. σημɛιονδɛητωναισθησɛωναγαπησις. Kαιγαρχωριςτηςχρɛιαςαγαπωνταιδι' αvτας, καιμαλλιστατωναλλωνηδιατωνομματων.
By nature humans thirst for knowledge. A sign of this is our love of the senses. Because irrespective of our needs we love our senses in themselves and most of all vision (eyesight).1
Is the Child Perceptions Questionnaire for 11–14 year olds sensitive to clinical and self‐perceived variations in orthodontic status?
Authors: Locker David , Jokovic Aleksandra , Tompson Bryan , Prakash Preeti 
Published: May 2007

Abstract –  Objectives:  To assess the association between scores on the Child Perceptions Questionnaire for 11–14 year olds (CPQ11–14) and clinical and self‐perceived measures of malocclusion.Methods:  Children were recruited from an orthodontic clinic just prior to starting orthodontic treatment. They completed a copy of the CPQ11–14 and a short questionnaire concerning their feelings about the condition of their teeth. Study models were taken and rated according to the Dental Aesthetic Index (DAI) and the Peer Assessment Rating (PAR) index by two sets of three examiners. Intra and inter‐rater reliabilities for the two sets of examiners ranged from 0.80 to 0.99. CPQ11–14 scores were calculated for the full 35‐item version and for 16 and 8‐item short forms by summing the item response codes. The association between these scores, the DAI and PAR ratings and self‐perceived measures of malocclusion were examined using appropriate parametric and nonparametric tests.Results:  Complete data were collected for 141 children, 63 boys and 78 girls. The mean age was 12.5 (SD = 1.0). DAI scores ranged from 17.0 to 58.0 with a mean of 35.0 (SD = 8.0). The distribution of subjects across the four severity categories was minor/none – 6.6%, definite – 35.2%, severe – 15.6% and handicapping 42.6%. PAR scores ranged from 8.0 to 66.0 with a mean of 31.4 (SD = 11.1). Eight percent had scores of 50 or above indicating marked deviation from an ideal occlusion. Both the long and the short forms of the CPQ11–14 identified substantial variability in the impacts of malocclusion. Correlations between CPQ11–14 scores and the orthodontic indices ranged from 0.26 to 0.31 (P < 0.01). There was a clear gradient in CPQ11–14 scores across four categories of the PAR based on quartiles. The gradient across the DAI categories was less clear. There were significant associations between all CPQ11–14 scores and the children's self‐ratings of oral health, ratings of the extent to which the condition of the teeth affected life overall and expressions of happiness with the appearance and arrangement of the teeth.Conclusion:  The results provide some evidence of the validity of the CPQ11–14 when used with children needing orthodontic treatment. However, because clinical samples are biased the study needs to be repeated in different treatment settings in order to confirm the utility of the measure.
Melatonin expression in periodontal disease
Authors: Gómez‐Moreno G. , Cutando‐Soriano A. , Arana C. , Galindo P. , Bolaños J. , Acuña‐Castroviejo D. , Wang H.‐L. 
Published: May 2007

Background and Objective: It was the purpose of this study to examine the relationship between periodontal diseases and melatonin level.Material and Methods: Forty‐six patients with periodontal disease, together with 26 age‐ and gender‐matched healthy controls, were included. Periodontal status was assessed using the Community Periodontal Index. Plasma and salivary melatonin levels were determined using specific commercial radioimmunoassays, whereas lymphocyte subpopulations (e.g. CD3, CD4, CD8, C19 and natural killer cells) were analyzed using flow cytometry.Results: Patients with periodontal disease had significantly (p < 0.001) lower plasma (9.46 ± 3.18 pg/mL) and saliva (2.55 ± 0.99 pg/mL) melatonin levels than healthy control patients (14.33 ± 4.05 and 4.22 ± 0.87 pg/mL, respectively). A biphasic relationhip was observed between plasma melatonin levels and Community Periodontal Indices. The plasma melatonin level was reduced in patients with a lower Community Periodontal Index value (1 or 2) and increased in patients with a higher Community Periodontal Index value (3 or 4). Salivary melatonin parallels the changes of plasma melatonin. The higher the Community Periodontal Index, the older the patient and the higher the total lymphocyte counts. CD4 concentrations also increased as the disease worsened.Conclusion: The results obtained from this study suggest that melatonin could act as a protective function in fighting periodontal infection. However, further studies in this area are encouraged.
Diabetes in the dental office: using NHANES III to estimate the probability of undiagnosed disease
Authors: Borrell L. N. , Kunzel C. , Lamster I. , Lalla E. 
Published: May 2007

Background and Objective:  Recent data have suggested that in the past 15 years there has been a dramatic increase in the incidence of diabetes mellitus in the USA. However, evidence suggests that approximately one‐third of diabetes cases remain undiagnosed. Because 60% of Americans see a dentist at least once per year for routine, nonemergent, care, it is reasonable to propose that the dental office can be a healthcare location actively involved in screening for unidentified diabetes.Material and Methods:  This study used NHANES III to develop a predictive equation that can form the basis of a tool to help dentists determine the probability of undiagnosed diabetes by using self‐reported data and periodontal clinical parameters routinely assessed in the dental office.Results:  Our analyses reveal that individuals with a self‐reported family history of diabetes, hypertension, high cholesterol levels and clinical evidence of periodontal disease bear a probability of 27–53% of having undiagnosed diabetes, with Mexican–American men exhibiting the highest probability and white women the lowest.Conclusion:  These findings suggest that the dental office could provide an important opportunity to identify individuals unaware of their diabetic status.
The interleukin‐10 promoter haplotype ATA is a putative risk factor for aggressive periodontitis
Authors: Reichert S. , Machulla H. K. G. , Klapproth J. , Zimmermann U. , Reichert Y. , Gläser C. H. , Schaller H. G. , Stein J. , Schulz S. 
Published: May 2007

Background and Objective:  Interleukin‐10 has been described as an anti‐inflammatory cytokine and a B‐cell proliferation factor. Promoter polymorphisms of the interleukin‐10 gene have been associated with altered interleukin‐10 expression. Therefore, the aim of this study was to evaluate three polymorphisms at positions −1082G>A, −819C>T and −590C>A in patients with generalized chronic periodontitis (n = 27) and generalized aggressive periodontitis (n = 32) in comparison with periodontitis‐free controls (n = 34).Material and Methods:  Interleukin‐10 promoter polymorphisms were analyzed by polymerase chain reaction with sequence‐specific primers (PCR‐SSP). Distributions of single alleles, genotypes and haplotypes were calculated by the chi‐square test. Risk factor analyses were carried out by logistic regression. Subgingival bacteria were subjected to molecular biological analyses using the micro‐Ident® test.Results:  The combination ATA/ATA was found only in patients with aggressive periodontitis (15.6 vs. 0.0%, p = 0.023). Taking into account age, gender, smoking and plaque level, an increased odds ratio (3.7, p = 0.04) for aggressive periodontitis was shown for subjects with the haplotype ATA. Prevotella intermedia was found to be decreased in ACC‐ positive (41.3 vs. 66.7%, p = 0.022), ATA‐positive (33.3 vs. 57.1%, p = 0.032) and ACC/ATA‐positive (20.0 vs. 55.9%, p = 0.002) individuals. In GCC/GCC‐positive subjects, P. intermedia occurred more frequently (86.7 vs. 42.3%, p = 0.002).Conclusion:  The haplotype ATA, which is known as a ‘low interleukin‐10 producer’ is a putative risk indicator for generalized aggressive periodontitis.
Buffering effect of a prophylactic gel on dental plaque in institutionalised elderly
Authors: Persson Anitha , Lingström Peter , Bergdahl Maud , Claesson Rolf , Dijken Jan W. V. van 
Published: May 2007

Objectives:  The effect of multiple daily applications of a prophylactic gel, with buffering substances, on plaque acidogenicity in elderly institutionalised individuals was evaluated.Background:  Many elderly suffer from reduced salivary flow, poor oral hygiene and increased levels of cariogenic bacteria and are considered to be at an increased risk for coronal and root caries. Reinforcing the buffering capacity of dental plaque by the addition of substances such as bicarbonate and phosphates may decrease their caries activity.Materials and methods:  Fourteen elderly, with subjective dry mouth, were treated for 16‐day‐periods at random with: (i) Profylin fluoride gel with buffering components; (ii) Profylin fluoride gel without buffering components and (iii) rinsing with water. Applications were made four times a day and each period was followed by a 2‐week wash‐out period. The plaque pH was registered after a carbohydrate challenge and the following were recorded before and after each test period: stimulated salivary secretion rate, buffer capacity, number Colony Farming Units (CFU) mutans streptococci, lactobacilli and a sample of Candida albicans on oral mucosa.Results:  Eleven participants (mean age 76.6 years) fulfilled the study. Changes in plaque pH measurements, when calculated as area under the curve (AUC6.2 and AUC5.7) values (pH × min), before and after each of the three treatments, showed no significant differences. A tendency to a higher plaque acidogenicity and amount of cariogenic microorganisms was found after the gel treatments. C. albicans was found in low levels.Conclusion:  Frequent applications of the gel did not result in an improved neutralising effect in the elderly. This may be caused by a combination of several factors, such as the level of oral dryness of the individuals and low solubility, release and retention of the gel substances in plaque. Instead, an increased plaque acidogenicity was noted.
Patient ratings of chewing ability from a randomised crossover trial: lingualised vs. first premolar/canine‐guided occlusion for complete dentures
Authors: Heydecke Guido , Akkad Ahmed Shadi , Wolkewitz Martin , Vogeler Michael , Türp Jens C. , Strub Joerg R. 
Published: May 2007

Background:  Complex procedures involving a facebow transfer and the use of lingualised teeth are deemed to have a positive influence on the chewing ability with complete dentures.Objectives:  To determine if patients’ ratings of their ability to chew depend on the method of complete denture fabrication.Methods:  Edentulous patients (n = 20) participated in a within‐subject crossover trial. Each patient received two sets of new complete dentures. One pair was manufactured based on intraoral tracing of centric relation and facebow transfer; semi‐anatomical teeth with lingualised occlusion denture (LOD) were chosen. The second pair was made using a simplified procedure without facebow transfer; jaw relations were recorded with wax occlusion rims, and anatomical teeth with a first premolar/canine‐guidance (CGD) were selected. The dentures were delivered in randomised order, and each was worn for 3 months. Three months after delivery, patients’ ratings of each new prosthesis were recorded on visual analogue scales for their ability to chew seven index foods. Repeated measurements analysis of variance was performed to investigate possible carry‐over effects accounting for confounding by treatment period.Results:  When comparing the two treatments, participants rated their ability to chew in general, to masticate carrots, hard sausage, steak and raw apple in particular, was significantly better with the CGD (anatomical teeth) than with the LOD (p < 0.05).Conclusion:  Comprehensive methods for the fabrication of complete dentures including semi‐anatomical lingualised teeth and a full registration do not seem to influence the perceived chewing ability, when compared with more simple procedures. Chewing ability for tough foods appears to benefit from the use of anatomical teeth.
Comparison of surface electromyographic (sEMG) activity of submental muscles between the head lift and tongue press exercises as a therapeutic exercise for pharyngeal dysphagia
Authors: Yoshida Mitsuyoshi , Groher Michael E. , Crary Michael A. , Mann Giselle Carnaby , Akagawa Yasumasa 
Published: May 2007

Objective:  The present study compared surface electromyographic (sEMG) activity obtained from the submental muscle group for a tongue press and a head lift exercise as potential therapeutic exercises for dysphagic elderly.Materials and methods:  Fifty‐three healthy volunteers with a mean age of 35.3 participated in this study. Subjects were required to perform an isometric task, pressing their tongue against the hard palate, and an isotonic task requiring sustained lingual force against the hard palate. Pressure sensors were used to measure the amount of lingual pressure against the hard palate. Submental sEMG data from these tasks were compared with those obtained from the isometric and isotonic aspects of a head lift exercise.Results:  No sEMG differences were identified between the isometric tongue press task and head lift exercise. Isotonic tongue press exercises resulted in significantly higher maximum and mean sEMG values compared with the isotonic head lift exercise (p < 0.05). The submental sEMG activity from the tongue press exercise was equal (isometric) to, or greater (isotonic) than comparable muscle activation obtained during the head lift exercise.Conclusions:  The tongue press exercise may be less strenuous than the head lift exercise while achieving the same therapeutic effect.
The Current Position of Statistics: A Personal View
Authors: Cox D.R. 
Published: May 2007

SummarySome current aspects of statistical work are reviewed under three broad headings, applied probability modelling, design of investigations and statistical analysis and interpretation of data. The emphasis is on applications in science and science‐based technology, although some incidental comments are made about statistics in public affairs. While no technical details are given, there is some discussion of potential fields for development. The choice of topics reflects the author's personal interests.