bluuebunny/crossref_metadata_2025 huggingface dataset:
Gonadotrophin‐Releasing Hormone Neurones in a Photoperiodic Songbird Express Fos and Egr‐1 Protein After a Single Long Day
Authors: Saab S. S. , Lange H. S. , Maney D. L .
Published: January 2010

Birds use a variety of environmental cues, such as day length, temperature and social interactions, to time reproductive efforts. For most seasonally breeding birds, day length is the most important cue and takes precedence over all others. Experimental manipulation of day length has shown that, in a number of galliformes and passeriformes, exposure to a single long day induces a rise in plasma luteinising hormone (LH). The mechanisms underlying this response are only beginning to be understood. In Japanese quail and Zonotrichia sparrows, one long day causes striking up‐regulation of the protein products of immediate early genes (IEGs) in the mediobasal hypothalamus, near gonadotrophin‐releasing hormone (GnRH) axons and terminals. Photoperiodic induction of the same proteins in the GnRH somata themselves, however, has not been described in these species. In the present study, we used immunohistochemistry to assay the induction of two IEGs, Fos and Egr‐1, in the GnRH somata of male and female white‐throated sparrows (Zonotrichia albicollis) exposed to a single long day. We found that immunoreactivity for both proteins increased in a subset of the GnRH neurones of the septo‐preoptic area by the morning after the long day. Photo‐induced expression of Egr‐1 or Fos protein in GnRH neurones was limited to a population of cells in the medial preoptic area. Males showed significantly greater induction of both proteins in this population of GnRH neurones than did females, which is consistent with the hypothesis that males may be more sensitive to photic cues. Overall, the results obtained suggest that photostimulation stimulates new protein synthesis in GnRH neurones on a relatively rapid time scale. Further research is required to determine whether the GnRH somata are themselves integrating photic cues, or whether they are responding rapidly to an increased demand for GnRH synthesis.
General quantitative genetic methods for comparative biology: phylogenies, taxonomies and multi-trait models for continuous and categorical characters
Authors: Hadfield J. D. , Nakagawa S.
Published: January 2010

Although many of the statistical techniques used in comparative biology were originally developed in quantitative genetics, subsequent development of comparative techniques has progressed in relative isolation. Consequently, many of the new and planned developments in comparative analysis already have well-tested solutions in quantitative genetics. In this paper, we take three recent publications that develop phylogenetic meta-analysis, either implicitly or explicitly, and show how they can be considered as quantitative genetic models. We highlight some of the difficulties with the proposed solutions, and demonstrate that standard quantitative genetic theory and software offer solutions. We also show how results from Bayesian quantitative genetics can be used to create efficient Markov chain Monte Carlo algorithms for phylogenetic mixed models, thereby extending their generality to non-Gaussian data. Of particular utility is the development of multinomial models for analysing the evolution of discrete traits, and the development of multi-trait models in which traits can follow different distributions. Meta-analyses often include a nonrandom collection of species for which the full phylogenetic tree has only been partly resolved. Using missing data theory, we show how the presented models can be used to correct for nonrandom sampling and show how taxonomies and phylogenies can be combined to give a flexible framework with which to model dependence.
Chronic malaria infections increase family inequalities and reduce parental fitness: experimental evidence from a wild bird population
Authors: Knowles S. C. L. , Palinauskas V. , Sheldon B. C.
Published: January 2010

Avian malaria parasites (Plasmodium) occur commonly in wild birds and are an increasingly popular model system for understanding host–parasite co-evolution. However, whether these parasites have fitness consequences for hosts in endemic areas is much debated, particularly since wild-caught individuals almost always harbour chronic infections of very low parasite density. We used the anti-malarial drug MalaroneTM to test experimentally for fitness effects of chronic malaria infection in a wild population of breeding blue tits (Cyanistes caeruleus). Medication caused a pronounced reduction in Plasmodium infection intensity, usually resulting in complete clearance of these parasites from the blood, as revealed by quantitative PCR. Positive effects of medication on malaria-infected birds were found at multiple stages during breeding, with medicated females showing higher hatching success, provisioning rates and fledging success compared to controls. Most strikingly, we found that treatment of maternal malaria infections strongly altered within-family differences, with reduced inequality in hatching probability and fledging mass within broods reared by medicated females. These within-brood effects appear to explain higher fledging success among medicated females and are consistent with a model of parental optimism in which smaller (marginal) offspring can be successfully raised to independence if additional resources become available during the breeding attempt. Overall, these results demonstrate that chronic avian malaria infections, far from being benign, can have significant effects on host fitness and may thus constitute an important selection pressure in wild bird populations.
Morphology, cytology and taxonomic remarks of four species ofStigeoclonium(Chaetophorales, Chlorophyceae) from Argentina
Authors: Michetti Karina M. , Leonardi Patricia I. , Cáceres Eduardo J.
Published: January 2010

Four species ofStigeocloniumfrom Argentina were studied by means of transmission electron microscopy and light microscopy. For species identification, we collected data related to the prostrate system and zoospore germination. We also determined the chromosome number for each species.Stigeoclonium aestivaleshowed a more developed erect system than the prostrate one, zoospore germination was predominantly of erect type and the chromosome number was 8.Stigeoclonium tenuepresented well developed, erect and prostrate systems, zoospore germination was initially of the prostrate type and the chromosome number was 5. InStigeoclonium variabilethe prostrate system predominated over the erect one, zoospore germination was strictly of the prostrate type and the chromosome number was 3.Stigeoclonium farctumpresented a more developed prostrate system than the erect one, zoospore germination was strictly of the prostrate type and the chromosome number was 8. The ontogeny of the zoospore germination was related to the final relative development of the prostrate and erect portions of adult thalli.
Genetic diversity of Gambierdiscus spp. (Gonyaulacales, Dinophyceae) in Japanese coastal areas
Authors: Kuno Sotaro , Kamikawa Ryoma , Yoshimatsu Sadaaki , Sagara Takefumi , Nishio Sachio , Sako Yoshihiko
Published: January 2010

The genetic diversity of the ciguatera fish poisoning‐related dinoflagellate distributed in Japanese coastal areas was investigated. The entire sequence of the 5.8S rRNA gene and two internal transcribed (ITS) regions were determined, which included putative pseudogenes, from 19 strains of dinoflagellates assigned to the genus Gambierdiscus Adachi et Fukuyo collected from Japanese subtropical and temperate coastal areas. The sequences obtained from the 19 strains were divided into two types based on sequence similarity. Here we designate the two types as type 1 and type 2. For the relationship between the genotypes and origins of the strains used, the strains collected from subtropical areas possessed the type 1 sequence; whereas those from temperate areas possessed the type 2. This observation led us to question former reputations that Gambierdiscus cells observed in Japanese temperate areas are immigrants from Japanese subtropical areas. Subsequently, we sequenced a part of the 18S rRNA gene from two strains from subtropical areas and two from temperate areas. Unfortunately, phylogenetic analysis including the sequences obtained from various gonyaulacales dinoflagellates failed to determine the species phylogenetically closely related to and possible origin(s) of the Gambierdiscus sp. from the Japanese coastal areas.
Phylogenetic position of a rare loricated green alga, Cephalomonas granulata N. L. Higinb. (Volvocales, Chlorophyceae)
Authors: Nakada Takashi , Soga Tomoyoshi , Tomita Masaru
Published: January 2010

Cephalomonas (Cp.) granulata N. L. Higinb. (Volvocales, Chlorophyceae), a rare volvocalean phytoflagellate, has recently been isolated from a paddy field in Japan and examined by light and fluorescence microscopy. The vegetative cells of Cp. granulata have granulate loricae and a characteristic mushroom‐like shape with a hemispherical to spherical anterior part and narrower posterior part. Cp. granulata has been classified among the Phacotaceae along with other loricated genera. However, its phylogenetic position has not been investigated using molecular phylogeny. To evaluate the phylogenetic position of Cephalomonas, the 18S rRNA gene sequence of the Japanese strain was determined. The phylogenetic analyses revealed that Cp. granulata was not closely related to other loricated taxa with known phylogenetic affinities, such as Phacotaceae sensu stricto (Phacotus, Pteromonas, and Wislouchiella) and Dysmorphococcus globosus. This indicates at least three independent origins of loricae within the Volvocales.
Recovering from recurrent mental health problems: Giving up and fighting to get better
Authors: Kartalova‐O'Doherty Yulia , Tedstone Doherty Donna
Published: January 2010

The purpose of this paper is to present selected findings of a grounded theory study that aims to explore individual processes and desired outcomes of recovery from recurrent health problems in order to build up a theoretical framework of recovery in an Irish context. Volunteers included mental health service users or participants of peer support groups who have experienced recurrent mental health problems for two or more years, consider themselves in improvement, and are willing to participate in individual interviews. The current paper is based on the analysis of 15 audiorecorded and transcribed interviews. We identified two open codes of ‘giving up’ and ‘fighting to get better’. Giving up was associated with accepting a passive identity of a patient with a chronic mental illness and a lack of intrinsic motivation to get better. Fighting had both positive (fighting for) and negative (fighting against) dimensions, as well as internal and external ones. The fight for recovery entailed substantial and sometimes risky effort. Starting such a fight required strong, self‐sustained motivation. Service providers might need to discuss internal and external motivators of fighting for recovery with service users, with a view to including such motivators in the care plans.
Confusion of recovery: One solution
Authors: Collier Elizabeth
Published: January 2010

This paper questions the current mental health discourse that offers new definitions of the concept of ‘recovery’ and offers a different perspective that aims to clarify its meaning. Confusion is caused when medical language continues to be used in discussions that aim to challenge traditional medical understanding of the term ‘recovery’ (meaning cure). Medical and non‐medical concepts of recovery are referred to interchangeably in many narratives and the common references to and acceptance of the Harding et al. papers and similar that report on how people can ‘get better’ from schizophrenia perpetuates this confusion. In this paper, it is suggested that ‘recovery’ should not be viewed as having new meaning, but that two different concepts have been confused, with the same word having been used to describe two completely different things altogether. This means that what is referred to in this paper as ‘medical’ recovery (traditional definitions of recovery that aims for cure), becomes subordinate to ‘life’ recovery (personal development and change) in which psychiatric classification might have no part in a person's understanding of their experience and where improving ‘symptoms’ could be irrelevant in the personal process of growth and discovery.
Systemic atherosclerosis in patients with perforating artery territorial infarction
Authors: Choi H.‐Y. , Yang J. H. , Cho H. J. , Kim Y. D. , Nam H. S. , Heo J. H.
Published: January 2010

Background:  Perforating artery territorial infarction (PAI) is usually a small artery disease (SAD). However, it may also result from branch artery occlusion or arterial embolism from the proximal atherosclerotic lesions. We hypothesized that patients with PAI caused by a SAD may have a distinct pattern of systemic artery involvement from those with PAI caused by large artery diseases.

Methods:  We investigated retrospectively 329 consecutive patients with PAI who had angiographic studies. Patients were grouped according to the presence or absence of atherosclerosis in the parent artery or relevant artery: no arterial lesion (NAL), relevant artery atherosclerosis (RAA) and parent artery atherosclerosis (PAA). The relevant artery was defined as any artery which can cause index stroke. The parent artery was defined as an original artery that branches out and forms small artery which was responsible for index PAI. Systemic evidence of atherosclerosis and risk factors were compared.

Results:  Of the 329 patients with PAI, 109 had RAA, 45 had PAA and 175 had neither RAA nor PAA. There were no differences amongst the groups in the classic risk factors for atherosclerosis. Evidence of atherosclerosis in arterial beds other than the relevant artery to the infarction (other cerebral arteries, coronary arteries, descending aorta and peripheral arteries) was significantly lower in the NAL group (49.7%) than in either the PAA group (88.9%) or RAA group (93.6%).

Conclusions:  Perforating artery territorial infarction with RAA or PAA when compared to PAI without atherosclerosis showed different involvement patterns of systemic atherosclerosis, suggesting potentially different aetiological mechanisms.
Lack of replication of KIF1B gene in an Italian primary progressive multiple sclerosis cohort
Authors: Martinelli‐Boneschi F. , Esposito F. , Scalabrini D. , Fenoglio C. , Rodegher M. E. , Brambilla P. , Colombo B. , Ghezzi A. , Capra R. , Collimedaglia L. , Coniglio G. , De Riz M. , Serpente M. , Cantoni C. , Scarpini E. , Martinelli V. , Galimberti D. , Comi G.
Published: January 2010

Background:  KIF1B gene represents the first non‐inflammatory gene with a putative role on axonal loss and neurodegeneration found to be associated with multiple sclerosis (MS). The objective of this study is to test the association of the rs10492972 C allelic variant of KIF1B gene in a large Italian cohort of patients with primary progressive and progressive relapsing MS (PPMS and PRMS), which represents a subtype of MS mainly driven by neurodegenerative phenomena.

Methods:  rs10492972 has been genotyped in an outbred sample of 222 primary PPMS and PRMS and 221 healthy controls of unique northern Italian origin using the TaqMan assay.

Results:  A non‐significant age‐ and sex‐adjusted odds ratio of 0.96 [95% confidence interval (CI) 0.71–1.31] has been found in C carriers, and a non‐significant risk of 0.99 [95% CI 0.77–1.63] in C carriers according to a dominant model. Stratification by sex, age at onset younger than 35 years and symptoms at the onset of the disease did not reveal any significant findings. No influence on disability progression, measured with the multiple sclerosis severity score, was found in C carriers.

Conclusions:  These results suggest that there is no effect in carrying the rs10492972 C variant on the risk of disease as well as on the rate of disability progression in a cohort of Italian patients with PPMS and patients with PRMS. These data need to be confirmed in an independent sample of patients with progressive MS.
What is Theological Interpretation? An Ecclesiological Reduction
Authors: TREIER DANIEL J.
Published: January 2010

This article addresses ‘theological interpretation’, first, by constructing a coherent narrative framework to account for its recent popularity via key players, common practices and a genealogy. Second, by addressing disagreements that remain within this movement via a kind of ‘ecclesiological reduction’, the article's descriptive starting point brings theological implications. In particular, strong parallels surface between the fortunes of theological interpretation and another essentially contested concept –‘postliberal’ theology. Both ‘postliberalism’ and ‘theological interpretation’ have fuzzy boundaries precisely due to their character as trans‐denominational forms of scholarly ecumenism through which God may help renew the church's engagement with Scripture in the post‐Christian West.
CASK phosphorylation by PKA regulates the protein–protein interactions of CASK and expression of the NMDAR2b gene
Authors: Huang Tzyy‐Nan , Chang Hui‐Ping , Hsueh Yi‐Ping
Published: January 2010

J. Neurochem. (2010) 112, 1562–1573.

Calcium/calmodulin‐dependent serine kinase (CASK), a causative gene in X‐linked mental retardation, acts as a multi‐domain scaffold protein and interacts with more than 20 cellular proteins in different subcellular regions of neurons. It is of interest, therefore, to explore whether post‐translational modification regulates CASK’s protein–protein interactions. Here, we provide evidence that CASK is phosphorylated by protein kinase A (PKA), identifying residue S562 in the PSD‐95‐Dlg‐ZO‐1 domain and residue T724 in the guanylate kinase domain as PKA sites by an in vitro PKA kinase reaction and site‐directed mutagenesis. Although the role of S562 phosphorylation is not clear, T724 phosphorylation up‐regulates the interaction between CASK and T‐box transcription factor T‐brain‐1 (Tbr‐1). NMDAR2b, a downstream target of the CASK‐Tbr‐1 complex, was then used to explore the significance of CASK phosphorylation by PKA. In cultured cortical neurons, the PKA pathway stimulates both the protein expression and the promoter activity of NMDAR2b. Deletion of the Tbr‐1‐binding sites greatly reduces the 3′‐5′‐cyclic AMP responsiveness of the NMDAR2b promoter, and the CASK T724A mutation does not promote the 3′‐5′‐cyclic AMP responsiveness of NMDAR2b. In conclusion, our data provide evidence that PKA phosphorylates CASK, regulates the nuclear function of CASK, and consequently modulates NMDAR2b expression.
Traditional Ecological Knowledge Trends in the Transition to a Market Economy: Empirical Study in the Doñana Natural Areas
Authors: GÓMEZ‐BAGGETHUN ERIK , MINGORRÍA SARA , REYES‐GARCÍA VICTORIA , CALVET LAURA , MONTES CARLOS
Published: January 2010

Abstract:  Researchers and conservation managers largely agree on the relevance of traditional ecological knowledge for natural resource management in indigenous communities, but its prevalence and role as societies modernize are contested. We analyzed the transmission of traditional knowledge among rural local people in communities linked to protected areas in Doñana, southwestern Spain. We studied changes in knowledge related to local practices in agriculture and livestock farming among 198 informants from three generations that cover the period in which the area transited from an economy strongly dependent on local ecosystem services to a market economy with intensified production systems. Our results suggest an abrupt loss of traditional agricultural knowledge related to rapid transformations and intensification of agricultural systems, but maintenance of knowledge of traditional livestock farming, an activity allowed in the protected areas that maintains strong links with local cultural identity. Our results demonstrate the potential of protected areas in protecting remaining bodies of traditional ecological knowledge in developed country settings. Nevertheless, we note that strict protection in cultural‐landscape‐dominated areas can disrupt transmission of traditional knowledge if local resource users and related practices are excluded from ecosystem management.
A new experimental model of focal seizures in the entorhinal cortex
Authors: Losi Gabriele , Cammarota Mario , Chiavegato Angela , Gomez‐Gonzalo Marta , Carmignoto Giorgio
Published: January 2010

Purpose:  Despite intensive studies, our understanding of the cellular and molecular mechanisms underlying epileptogenesis remains largely unsatisfactory. Our defective knowledge derives in part from the lack of adequate experimental models of the distinct phases that characterize the epileptic event, that is, initiation, propagation, and cessation. The aim of our study is the development of a new brain slice model in which a focal seizure can be repetitively evoked at a precise and predictable site.

Methods:  Epileptiform activities were studied by fast Ca2+ imaging coupled with simultaneous single and double patch‐clamp or extracellular recordings from neurons of entorhinal cortex (EC) slices from Wistar rats and C57BL6J mice at postnatal days 13–17.

Results:  In the presence of 4‐aminopyridine (4‐AP) and low Mg2+, activation of layer V–VI neurons by local N‐methyl‐d‐aspartate (NMDA) applications evolved into an ictal discharge (ID) that propagated to the entire EC. NMDA‐evoked IDs were similar to spontaneous events. IDs with similar pattern and duration could be repetitively triggered from the same site by successive NMDA stimulations. The high ID reproducibility is an important feature of the model that allowed testing of the effects of currently used antiepileptic drugs (AEDs) on initiation, propagation, and cessation of focal ictal events.

Conclusions:  By offering the unique opportunity to repetitively evoke an ID from the same restricted site, this model represents a powerful approach to study the cellular and molecular events at the basis of initiation, propagation, and cessation of focal seizures.
Aggravation of seizure‐associated microvascular injuries by ibuprofen may involve multiple pathways
Authors: Régnier Angélique , Vicaut Eric , Mraovitch Sima
Published: January 2010

Purpose: Recently we reported that intrathalamic microinjection of carbachol triggers generalized convulsive seizures (GCS) followed by severe inflammatory response including edema, microhemorrhages, and subsequent degeneration of amygdaloallocortical area. Our further observations of increased expression of tumor necrosis factor alpha (TNF‐α) and interleukin (IL)‐1β immunoreactivity (IR) confirmed the inflammatory nature of the brain damage following GCS. In the presented experiments, we addressed possible effects of a nonspecific cyclooxygenase (COX) inhibitor (ibuprofen), in the development of inflammatory response following thalamic‐induced GCS.

Methods: In male Wistar rats, intrathalamic microinjection of carbachol (55 nm, 100 nl) within 2 h induced three to four episodes of GCS of an average duration of 57 s, each which led to the development of edema associated with microhemorrhages at 72 h and changes in expression of TNF‐α/IL‐1β IR in the amygdaloallocortical area as revealed by immunohistochemistry at 24 h.

Results: Ibuprofen when administered intraperitoneally 30 min after the episode of GCS dramatically increased edema and microhemorrhages. It also increased expression of TNF‐α/IL‐1β in microvessels and decreased IL‐1β IR in microglia/macrophages.

Conclusions: Experiments suggest that in our model, inhibition of COX pathway early after GCS may increase rather than reduce the inflammatory consequences of GCS, suggesting that COX products may have a negative feedback effect on the development of edema by modifying the expression of “proinflammatory” cytokines. There is also a possibility that ibuprofen may exert its action through other than COX‐associated pathways.
Explaining agricultural productivity growth: an international perspective
Authors: Headey Derek , Alauddin Mohammad , Rao D.S. Prasada
Published: January 2010

This article presents multi‐output, multi‐input total factor productivity (TFP) growth rates in agriculture for 88 countries over the 1970–2001 period, estimated with both stochastic frontier analysis (SFA) and the more commonly employed data envelopment analysis (DEA). We find results with SFA to be more plausible than with DEA, and use them to analyze trends across countries and the determinants of TFP growth in developing countries. The central finding is that policy and institutional variables, including public agricultural expenditure and proagricultural price policy reforms, are significant correlates of TFP growth. The most significant geographic correlate of TFP growth is distance to the nearest OECD country.
An error corrected almost ideal demand system for major cereals in Kenya
Authors: Nzuma Jonathan M. , Sarker Rakhal
Published: January 2010

Despite significant progress in theory and empirical methods, the analysis of food consumption patterns in developing countries, particularly those in Sub‐Saharan Africa (SSA), has received very limited attention. An attempt is made in this article to estimate an Error Corrected Almost Ideal Demand System for four major cereals consumed in Kenya employing annual data from 1963 to 2005. This demand system performs well on both theoretical and empirical grounds. The symmetry and homogeneity conditions are supported by the data and the Le Chatelier principle holds. Empirically, all own‐price elasticities are negative and significant at 5% level and irrespective of the time horizon, maize, wheat, rice, and sorghum may be considered as necessities in Kenya. While the expenditure elasticities of all four cereals are positive, they are inelastic both in the short run and in the long run. Finally, wheat and rice complement maize consumption in Kenya while sorghum acts as a substitute. Since cereal consumers have price and income inelastic responses, a combination of income and price‐oriented policies could improve cereal consumption in Kenya.
Linkages between the farm and nonfarm sectors at the household level in rural Ghana: a consistent stochastic distance function approach
Authors: Anríquez Gustavo , Daidone Silvio
Published: January 2010

This article explores the effects within households of an expanding rural nonfarm (RNF) sector in Ghana. We ask whether the growing RNF sector allows for economies of diversification within farms, how it affects household input demands, and whether it has measurable effects in overall household production efficiency. We explore the intrahousehold linkages between agricultural and RNF activities, first assuming perfectly competitive input and output markets and then with market failures, in particular missing labor and credit markets. We then measure these linkages using a household level input distance function, finding high levels of inefficiency in Ghanaian farms. Also, there are cost‐complementarities between the RNF sector and the agricultural sector, particularly with food crops in which the poorest tend to specialize. The expansion of the RNF sector increases demand for most inputs including agricultural land. Finally, we show that smaller farms tend to be more efficient, and that RNF output is helping the farm household to become more efficient, but the latter result is not robust.
Neural correlates of movement generation in the ‘at‐risk mental state’
Authors: Broome M. R. , Matthiasson P. , Fusar‐Poli P. , Woolley J. B. , Johns L. C. , Tabraham P. , Bramon E. , Valmaggia L. , Williams S. C. R. , Brammer M. J. , Chitnis X. , McGuire P. K.
Published: January 2010

Broome MR, Matthiasson P, Fusar‐Poli P, Woolley JB, Johns LC, Tabraham P, Bramon E, Valmaggia L, Williams SCR, Brammer MJ, Chitnis X, McGuire PK. Neural correlates of movement generation in the ‘at‐risk mental state’.

Objective:  People with ‘prodromal’ symptoms have a very high risk of developing psychosis. We examined the neurocognitive basis of this vulnerability by using functional MRI to study subjects with an at‐risk mental state (ARMS) while they performed a random movement generation task.

Method:  Cross‐sectional comparison of individuals with an ARMS (n = 17), patients with first episode schizophreniform psychosis (n = 10) and healthy volunteers (n = 15). Subjects were studied using functional MRI while they performed a random movement generation paradigm.

Results:  During random movement generation, the ARMS group showed less activation in the left inferior parietal cortex than controls, but greater activation than in the first episode group.

Conclusion:  The ARMS is associated with abnormalities of regional brain function that are qualitatively similar to those in patients who have recently presented with psychosis but less severe.
Students’ clinical experience on outreach placements
Authors: Smith M. , Lennon M. A. , Robinson P. G.
Published: January 2010

Primary care outreach placements increasingly feature in UK undergraduate dental curricula. The profile of clinical work undertaken on placement may differ from traditional hospital‐based programmes and between outreach settings. An appreciation of any differences could inform curriculum development.

Objective:  To compare the profiles of clinical work experienced on a traditional hospital‐based programme and outreach placements in different settings.

Setting:  One dental hospital and eight existing primary care block placements in England.

Subjects and methods:  Subjects were four cohorts of senior dental students in one UK dental school. Departmental records provided data on students’ clinical experience in different settings and their achievement of placement learning objectives. Descriptive statistics for groups were compared.

Main outcome measures:  (1) Counts of patients encountered and of clinical procedures completed in the following categories: simple plastic restorations, endodontics, cast restorations, dentures, extractions and children’s dentistry. (2) Student perceptions of placement learning reported via Likert scales.

Results:  Outreach students encountered twice as many patients and typically completed about three times as much clinical work as students in the hospital, e.g. 44 cf 16 simple plastic restorations, seven cf two endodontic procedures. There were variations in profiles by setting. For example, amalgam being more likely to be used on outreach especially in the General Dental Service; more children’s dentistry in community services and more extractions in Dental Access Centres. Students reported learning outcomes generally being achieved (average 94%) although with some variation by setting.

Conclusion:  Dental outreach training greatly increases the quantity of students’ clinical experience in everyday dentistry compared to a hospital‐based programme. Placements also increase awareness of service delivery and develop clinical skills. There are appreciable variations between outreach settings possibly reflecting their purposes. Multiple contrasting outreach placements for each student might increase the uniformity of learning experiences.
The role of ultraviolet radiation in melanomagenesis
Authors: Von Thaler Anna‐Katharina , Kamenisch York , Berneburg Mark
Published: January 2010

Please cite this paper as: The role of ultraviolet radiation in melanomagenesis. Experimental Dermatology 2010; 19: 81–88.

Abstract:  The role of ultraviolet radiation (UV) in the pathogenesis has been discussed controversially for many decades. Studies in mice (SCID, HGF/SF, SV40T) which develop malignant melanoma, show a role of UVB in melanomagenesis. In contrast to this, the role of UVA is less clear. We will review the recent in vitro and in vivo data in support of the hypothesis that UVA is also involved in the development of malignant melanoma. The role of UVA in p53 activation, apoptosis, cell cycle arrest and photoproduct formation is discussed.
Retrospective study on traumatic dental injuries in preschool children at Kyung Hee Dental Hospital, Seoul, South Korea
Authors: Choi Sung Chul , Park Jae Hong , Pae Ahran , Kim Jong Ryul
Published: January 2010

Abstract –  The purpose of this study was to analyse the traumatic dental injuries (TDI) of Korean preschoolers by investigating the occurrence, type, area, cause, injured region, seasonal variation and the interval between injury and treatment. In this study, data from 1856 preschoolers aged 4 months to 6 years and 11 months (mean age : 3.6 ± 1.6) were used, out of a total of 2761 patients who attended the Department of Pediatric Dentistry, Kyung Hee Dental Hospital for TDI between January 1998 and December 2007. All the data were statistically analysed using the anova and chi‐square statics. Most of the patients were 1–2, 2–3 years old (24.5%, 25.4%) and boys were 1.67 times more likely to have TDI. The most common cause, location and seasonal variation of the trauma, were respectively falling (50.8%), at home (48.8%) and late spring. The treatment intervals usually occurred within a day. Most of the injuries involved single (47%) or double (38%) tooth/teeth. However, car accidents or sports trauma often involved multiple teeth. In both primary and permanent dentition, the most common teeth injured were maxillary central incisors (72.6%), and periodontal injury was caused by subluxation or concussion. Among the various types of hard tissue injuries, enamel fracture in the primary dentition (35.0%) and enamel‐dentin fracture in the permanent dentition (45.8%) were the most common types.
In vitro comparison of the flexibility of different splint systems used in dental traumatology
Authors: Mazzoleni Sergio , Meschia Guglielmo , Cortesi Raffaello , Bressan Eriberto , Tomasi Cristiano , Ferro Roberto , Stellini Edoardo
Published: January 2010

Abstract –  Aim:  The aim of the study was to evaluate the flexibility of five different splint systems [polyethylene fibre‐reinforced splint (Ribbond® THM, Ribbond Inc., Seattle, WA, USA), resin splint (RS), wire‐composite splint (WCS), button‐bracket splint (BS) and titanium trauma splint (TTS)] commonly used in clinical practice for the treatment of dental traumatic injuries involving the periodontal supporting tissues.

Materials and methods:  For the experimental study, a resin cast of the upper arch was manufactured, where teeth 11, 12 and 21 (used for the stress analysis) were inserted in a non‐rigid fashion so as to allow for replacement, whereas the other teeth were permanently fixed to the corresponding sockets.

Two different test sessions were performed for each splint: (i) stress analysis with increasing intensity ranging between 0 and 50 N directed along the tooth’s longitudinal axis; (ii) stress analysis with 45° of oblique force of increasing intensity ranging between 0 and 30 N.

For each loading direction, five recordings were conducted without a splint, followed by five with the splint applied. The energy required to modify the position of the teeth was calculated for both the splinted and un‐splinted teeth and the difference between the two values was determined.

Energy variation was assessed for the testing of both axial (ΔEa) and oblique force (ΔEo).

ΔE represents the rigidity index of the analysed contention devices: high ΔE values correspond to high rigidity materials.

Results:  The RS showed the highest ΔE value for the axial stress analysis, whereas the highest ΔE value at a 45° was recorded for the WCS and RS.

For both tests, the lowest ΔE values were recorded for the TTS and Ribbond THM splints.

Conclusions:  The data show that the contention devices with the highest flexibility are the TTS and the Ribbond THM as they exhibit a lower energy variation needed for splint deformation compared with the other materials that were examined.
Social judgements made by children in relation to visible incisor trauma
Authors: Rodd Helen D. , Barker Chris , Baker Sarah R. , Marshman Zoe , Robinson Peter G.
Published: January 2010

Abstract –  Aim:  There is evidence to suggest that negative social judgements are made on the basis of poor dental aesthetics. This study sought to determine how children view other children with visible incisor trauma.

Material and methods:  Year 7 (aged 11–12 years) and year 10 (aged 14–15 years) school children (the participants) were invited to look at colour photographs of four different children’s faces and to make a social judgement about these children (the subjects). Participants were randomly allocated either: (i) pictures of children with visible incisor trauma or, (ii) pictures of the same children whose photographs had been digitally modified to restore incisor aesthetics. Using a previously validated child‐centred questionnaire, participants rated subjects using a four‐point Likert scale for three negative and six positive attributes. Total attribute scores were tested for significant differences, according to whether the subject had visible incisor trauma or not, using multivariate analysis of variance (P < 0.05, manova).

Results:  291 children completed the questionnaires, giving a response rate of 73%. Year 7 children viewed children with visible incisor trauma more negatively than the same child with normal incisor appearance. However, the converse was true for year 10 participants.

Conclusion:  Findings from this study concur with those from adult populations in that negative social judgements may be made on the basis of poor dental appearance. Interestingly, this would not appear to be the case in adolescence, which may relate to high levels of self‐monitoring in this age‐group. In view of the importance of appearance in adolescent social interaction, aesthetic dental treatment for children with incisor injury may yield important psychosocial benefits.
Submental intubation in panfacial injuries: our experience
Authors: Garg Munish , Rastogi Bhawna , Jain Manish , Chauhan Himanshu , Bansal Vishal
Published: January 2010

Abstract –  Panfacial fractures present a unique set of problems to the anaesthesiologist and surgeon. Airway management in panfacial fractures is still a challenge to the anaesthesiologist as all modalities available such as orotracheal intubation, nasotracheal intubation, tracheostomy, etc., have their own advantages and disadvantages. When all the conventional modalities to secure airway seem unsuitable then submental route offers an excellent alternative to manage airway in such patients. Here we describe our experience with submental intubation technique in 10 patients with panfacial injuries over a period of two years.
Epistemological Objections to Platonism
Authors: Liggins David
Published: January 2010

Many philosophers posit abstract entities – where something is abstract if it is acausal and lacks spatio‐temporal location. Theories, types, characteristics, meanings, values and responsibilities are all good candidates for abstractness. Such things raise an epistemological puzzle: if they are abstract, then how can we have any epistemic access to how they are? If they are invisible, intangible and never make anything happen, then how can we ever discover anything about them? In this article, I critically examine epistemological objections to belief in abstract objects offered by Paul Benacerraf, Colin Cheyne and Hartry Field.
Scientific Representation
Authors: Suárez Mauricio
Published: January 2010

Scientific representation is a currently booming topic, both in analytical philosophy and in history and philosophy of science. The analytical inquiry attempts to come to terms with the relation between theory and world; while historians and philosophers of science aim to develop an account of the practice of model building in the sciences. This article provides a review of recent work within both traditions, and ultimately argues for a practice‐based account of the means employed by scientists to effectively achieve representation in the modelling sciences.
The Vibrational Behavior of a Turbine Rotor Containing a Transverse Crack
Authors: Grabowski B.
Published: January 2010

A modal formulation is used to investigate the vibrational behavior of flexible single or coupled rotors containing a transverse crack. A theoretical model has been developed to simulate the crack mechanism. The transformed time variable system is numerically integrated. The modal analysis shows particularly the strong dependence of the vibrational behavior on the crack position. The vibrations, excited by the crack, are independent of the unbalance.
The Dynamics of Rotor-Bearing Systems With Axial Torque—A Finite Element Approach
Authors: Zorzi E. S. , Nelson H. D.
Published: January 2010

This study investigates the effect of constant axial torque on the dynamics of rotorbearing systems using a finite element model. The finite element equation of motion is formulated using the variational approach and the inclusion of axial torques gives rise to an incremental torsional stiffness matrix. This matrix is circulatory since the system is non-conservative. The finite element model is used to determine the static buckling torques and the critical speeds of a uniform shaft for short and long bearings.
Modeling and Experimental Analysis of A Fluidic Generator
Authors: Tacey C. F. , Verrier F. E. , Wood L. R. , Mitchell L. D. , Kurstedt H. A.
Published: January 2010

A fluidic generator is a device that converts air flow into electrical power. The mechanical portion of this generator is modeled for its dynamic characteristics so that optimization of the power output may be attained through mechanical system modification. Further, a regression analysis is carried out on experimentally obtained data to allow specific definition of defects in the analytic model. A lumped parameter mechanical network is used to model the system. Structural inertia, stiffness, viscous damping, and internal structural damping models are used to model a corrugated diaphragm, a connecting rod, coupling nuts, and a cantilever laminated reed. Special attention is given to the modeling of the corrugated diaphragm laminated reed. A computer algorithm, IMPV, (Impedance Modeling Program, version V), is used to solve the impedance formulation of this model. The result is the dynamic compliance matrix of the structural assembly. Specifically, the displacement response at the end of the reed is computer per unit force applied at the center of the diaphragm. The resultant dynamic transfer compliance is compared to the experimental Fast Fourier Transform (FFT) dynamic transfer compliance as measured on the actual structure.
The Characterization of Cam Drive System Windup
Authors: Szakallas L. E. , Savage M.
Published: January 2010

The vibration in a cam driven mechanism due to drive system windup can be a serious problem at high speeds. A single degree of freedom model of this source of vibration shows that it is a self-induced nonlinear vibration. By dimensional analysis, two ratios are established to characterize the level of vibration. Maximum drive system windup and maximum radial follower force ratios are presented in chart form to characterize the vibration level. Systems studied are harmonic and cycloidal rises with open and closed track cam surfaces.
Unbalanced Response of a Large Rotor-Pedestal-Foundation System Using an Elastic Half-Space Soil Model
Authors: Ruhl R. L. , Conry T. F. , Steger R. L.
Published: January 2010

The unbalanced response of a large rotor-pedestal-foundation system using an elastic half space soil model was determined. The effective stiffness and damping terms between the foundation and soil were determined from the elastic half space soil model. The rigid body equations of motion of the foundation were derived subject to applied forces from the bearing-support structure and from the springs and dashpots representing the soil. An impedance matrix representing the relationship between the bearing-support structure forces and the corresponding displacements was then derived and matched with the finite element model of the turborotor system. The analytical results of this investigation were compared with test data from a recirculating gas fan at a power plant installation. There was very good agreement between the analysis and the test data. This is the first time a realistic coupling of rotor models and foundation-soil models has been accomplished. This method of analysis should be the basis for the design of rotor-bearing-foundation-soil systems.
Constant-Deflection Rolls—A New Solution to an Old Problem
Authors: Pessen D. W.
Published: January 2010

The problem of designing a set of rolls exerting a uniform pressure on material passing between them has elicited many different solutions, none quite satisfactory. A new solution, presented here, uses composite rolls having a cigar-shaped inner core and a cylindrical outer shell, the gap between them being filled with a soft elastomer containing approximately 15 percent air bubbles. The core profile is calculated according to equations derived here. The solution produces even roll pressure for any load, without the need for making adjustments to match changing loads. At the same time, the solution is mechanically very simple and reliable.
Optimization of Die Profiles for Deep Drawing
Authors: Conry T. F. , Odell E. I. , Davis W. J.
Published: January 2010

This paper develops a procedure for the optimization of dies used in the deep drawing process. Previous efforts in this area are initially related. Considerable discussion is then devoted to the problem formulation. To effect the problem’s solution, several techniques are merged including the use of cubic and quartic splines, regression curve fitting and the techniques of constrained optimization. Computational results and conclusions are given.
Large System Optimization Using Decomposition with Soft Specifications
Authors: Siddall J. N. , Michael W. K.
Published: January 2010

A method of optimizing large systems is described in which decomposition is used based on the use of trade-off curves and the concept of soft specifications. A generalized formulation is provided and results of a practical example are given.
Computational Enhancements to the Method of Multipliers
Authors: Root R. R. , Ragsdell K. M.
Published: January 2010

Transformation or penalty function techniques have enjoyed wide popularity for the solution of nonlinear programming problems in recent years. Many methods have been proposed in this class, including the Method of Multipliers. In this paper we present two enhancements which may be used with any transformation technique. The first is a technique for direct handling of variable bounds, and the second is a problem scaling algorithm. Both techniques have been implemented in connection with a Method of Multipliers code, BIAS, and applied to 23 test problems. The numerical results indicate a significant increase in the robustness and overall efficiency of the transformation method employed.
Disc Vibration - Rotating Blade and Stationary Vane Interaction
Authors: Kushner F.
Published: January 2010

Only in rare cases does the vibration of a bladed disc assembly give concern for possible fatigue failures due to disc modes. This paper describes cases which should be investigated and outlines methods that can be used to prevent failures. Two types of bladed discs are treated; centrifugal applications with radial blades and those used for axial turbines or compressors. However, the theory is applicable to other discs. Analysis is presented showing cases of significant minor resonances over and above disc critical speeds.