bluuebunny/crossref_metadata_2025_split huggingface dataset:
Status of research on soil microsymbionts in Uganda
Authors: Nkwiine C. , Rwakaikara‐Silver M. C. 
Published: July 2007

AbstractA symbiotic relationship involves two or more organisms living together for mutual benefit(s). Neither partner could do well without the other. Symbionts are the individual partners in the relationship. Microsymbiosis is a relationship in which one of partners is a micro‐organism. Most of the symbioses involve higher plants acting as hosts to micro‐organisms. Microsymbionts play a major role in plant nutrition especially for nitrogen, phosphorus and water availability in both natural and agricultural ecosystems. They are a valuable resource for national development especially to countries, like Uganda, whose economies are heavily agro‐based. This review gives an inventory of the present knowledge on microsymbionts in Uganda and identifies future priorities for research, application and capacity building. In Uganda, not much is known or has been done regarding microsymbionts and their importance in both natural and agroecosystems. This may be associated with the fact that there are few scholars in the field of soil science available in the country. There is no specific policy on the conservation of microsymbionts. Attempts have been made on production and use of Rhizobium inoculants for promotion of the role of legumes in agricultural production. Other symbioses like mycorrhizae, Azolla and Frankia have not been exploited. Awareness raising and in‐depth research on soil microsymbionts’ production and use are recommended.
A review of studies on decomposer microbiota in Uganda
Authors: Rwakaikara Silver M. C. , Nkwiine C. 
Published: July 2007

AbstractSoil microflora and fauna participate in many ecosystem functions including organic matter decomposition and nutrient cycling. These processes significantly control natural and agro‐ecosystems productivity particularly in Uganda. The decomposer microbiota is poorly studied despite voluminous data on the processes involved. Currently there is scanty information on the diversity, distribution, abundance, population dynamics, biochemical capabilities of these organisms and how the latter relate to the above ground biodiversity and the environment as a whole. Definite rather than deductive knowledge is required for conservation and sustainable management of these resources. Immediate research programmes are recommended to address gaps in scientific and socio‐economic aspects of micro‐decomposers and related fields. Equally crucial is the review of existing policies, how they relate to belowground biodiversity and identify gaps and avenues of influencing formulation of pertinent instruments. In addition, capacity building, both physical and human to handle the challenge(s) effectively is obligatory.
The role of sex steroids in controlling pubertal growth
Authors: Perry R. J. , Farquharson C. , Ahmed S. F. 
Published: July 2007

SummaryLongitudinal growth, which is primarily due to chondrocytic activity at the level of the epiphyseal growth plate, is influenced by many hormones and growth factors in an endocrine and paracrine manner. Their influence is even more complex during the accelerated growth period of puberty that accounts for about 20% of final adult height. Although abnormalities of growth during puberty are very common, the underlying mechanisms that govern the beginning and cessation of pubertal growth at the level of the growth plate are poorly understood. Sex steroids play a crucial role in pubertal growth both at the systemic level via the GH/IGF‐1 axis and at the local level of the epiphyseal growth plate. In both sexes it is now accepted that oestrogen is the critical hormone in controlling growth plate acceleration and fusion. This paper reviews the mechanisms that influence pubertal growth and the problems that are associated with disorders of gonadal function.
Prolonged human chorionic gonadotrophin stimulation as a tool for investigating and managing undescended testes
Authors: Dixon J. , Wallace A. M. , O'Toole S. , Ahmed S. F. 
Published: July 2007

SummaryObjective  To observe the outcome in a group of children with undescended testes (UDT) given prolonged human chorionic gonadotrophin (hCG) stimulation as part of their management.Study design  Retrospective review of 16 prepubertal boys given intramuscular hCG, 1500 U, on Days 1, 2 and 3 and then twice a week for 2 weeks with assessment of serum testosterone (T), SHBG, dihydrotestosterone (DHT) and androstenedione (A) on Days 1, 4 and 22.Results  In seven boys (44%), peak rise in T was by Day 4; in 5 boys (31%), the rise was by Day 22 and in the remainder, serum T stayed low. The median Day1 testosterone : androstenedione (T : A) ratio rose from 0·4 (range 0·2–1·5) to 1·7 (range 0·2–5·3) at Day 4 (P < 0·05) with no further rise by Day 22. The median dihydrotestosterone : testosterone ratio (DHT : T) at Day 1 and Day 4 remained unchanged. SHBG levels were more likely to be lower at Day 22 than at Day 4. The mean testosterone : SHBG (T : SHBG) ratio as a marker of androgen sensitivity was 0·2 (1SD 0·1). Bilateral testicular descent deemed immediate surgery unnecessary in 3 out of 15 (20%) boys where outcome data were available.Conclusion  Whilst a 3‐day hCG stimulation regimen may exclude 17β‐hydroxysteroid dehydrogenase‐3 and 5α‐reductase deficiencies, some boys with cryptorchidism may require more prolonged stimulation to assess androgen production and sensitivity. The possibility that this regimen leads to a reduced need for orchidopexy requires further exploration.
Establishment of testicular endocrine function impairment during childhood and puberty in boys with Klinefelter syndrome
Authors: Bastida María Gabriela , Rey Rodolfo A. , Bergadá Ignacio , Bedecarrás Patricia , Andreone Luz , Del Rey Graciela , Boywitt Adriana , Ropelato María Gabriela , Cassinelli Hamilton , Arcari Andrea , Campo Stella , Gottlieb Silvia 
Published: July 2007

SummaryObjective  To precisely characterize the chronology of testicular endocrine function impairment during childhood and adolescence in patients with Klinefelter syndrome.Design  Retrospective chart review.Patients  A total of 29 boys with Klinefelter syndrome with up to 12·3 years follow‐up.Measurements  Clinical features and serum hormone levels were analysed during follow‐up.Results  Of the 29 patients, 16 were prepubertal and 13 had already entered puberty at their first visit. Fifteen patients were followed up through late puberty. Before puberty, LH, FSH, testosterone, anti‐Müllerian hormone (AMH) and inhibin B were within the expected range in almost all cases. However, levels of the inhibin α‐subunit precursor Pro‐αC were in the lowest levels of the normal range in most cases. During puberty, FSH levels increased earlier and more markedly than LH. Inhibin B and AMH declined to abnormally low or undetectable levels in advanced pubertal stages. Although testosterone and Pro‐αC levels were within the reference ranges in most cases, they were abnormally low for the observed LH values.Conclusions  In Klinefelter syndrome, a mild Leydig cell dysfunction is present from early childhood in most cases and persists throughout puberty. Sertoli cell function is normal until mid puberty, when a dramatic impairment is observed.
Screening patients with sensorineural hearing loss for vestibular schwannoma using a Bayesian classifier
Authors: Nouraei S.A.R. , Huys Q.J.M. , Chatrath P. , Powles J. , Harcourt J.P. 
Published: July 2007

Objectives:  Selecting patients with asymmetrical sensorineural hearing loss for further investigation continues to pose clinical and medicolegal challenges, given the disparity between the number of symptomatic patients, and the low incidence of vestibular schwannoma as the underlying cause. We developed and validated a diagnostic model using a generalisation of neural networks, for detecting vestibular schwannomas from clinical and audiological data, and compared its performance with six previously published clinical and audiological decision‐support screening protocols.Design:  Probabilistic complex data classification using a neural network generalization.Settings:  Tertiary referral lateral skull base and a computational neuroscience unit.Participants:  Clinical and audiometric details of 129 patients with, and as many age and sex‐matched patients without vestibular schwannomas, as determined with magnetic resonance imaging.Main outcome measures:  The ability to diagnose a patient as having or not having vestibular schwannoma.Results:  A Gaussian Process Ordinal Regression Classifier was trained and cross‐validated to classify cases as ‘with’ or ‘without’ vestibular schwannoma, and its diagnostic performance was assessed using receiver operator characteristic plots. It proved possible to pre‐select sensitivity and specificity, with an area under the curve of 0.8025. At 95% sensitivity, the trained system had a specificity of 56%, 30% better than audiological protocols with closest sensitivities. The sensitivities of previously‐published audiological protocols ranged between 82–97%, and their specificities ranged between 15–61%.Discussion:  The Gaussian Process ORdinal Regression Classifier increased the flexibility and specificity of the screening process for vestibular schwannoma when applied to a sample of matched patients with and without this condition. If applied prospectively, it could reduce the number of ‘normal’ magnetic resonance (MR) scans by as much as 30% without reducing detection sensitivity. Performance can be further improed through incorporating additional data domains. Current findings need to be reproduced using a larger dataset.
Columella stabilising suture
Authors: Kunanandam T. , Sheikh S. , Hilmi O.J. 
Published: July 2007

Keypoints• Caudal septal deformities if uncorrected can lead to poor functional and cosmetic outcomes.• Adequate fixation of the septum to the maxillary spine is paramount in correcting these deformities.• We describe a simple technique for securing the caudal septum to the maxillary spine that stabilises it in all three planes.
Free radial forearm flapversuspectoralis major myocutaneous flap reconstruction of oral and oropharyngeal defects: a cost analysis
Authors: De Bree R. , Reith R. , Quak J.J. , Uyl‐de Groot C.A. , Van Agthoven M. , Leemans C.R. 
Published: July 2007

Objectives: The free radial forearm flap has replaced the pedicled pectoralis major myocutaneous flap and it has become the ‘workhorse flap’ used by many head and neck reconstructive surgeons for soft tissue reconstructions. Cost implications of radial forearm flap reconstruction within the context of the overall health care in a particular system need to be investigated particularly before it is labelled as ‘costly only’.Design and Setting: Forty patients who underwent immediate free radial forearm flap reconstruction for oral or oropharyngeal soft tissue defects were matched with patients who underwent pectoralis major myocutaneous flap reconstruction for similar defects. The 2 years of which the overall management costs according to the hospital perspective were calculated were divided into four periods: operative period, the postoperative phase, follow‐up during first year and follow‐up during second year after discharge.Results: The total costs within the first 2 years were comparable at ∼50 000 euros. The lower costs of hospital admission (24 daysversus28 days;P = 0.005) in the postoperative phase outweighed the higher costs of the surgical procedure (692 minversus462 min;P < 0.005) in radial forearm flap patients when compared with pectoralis major flap patients.Conclusions: Oral and oropharyngeal reconstruction with radial forearm flap is not more costly than pectoralis major flap reconstruction. Given the better functional outcome and the present cost analysis, reconstruction of oral and oropharyngeal defects is preferably performed using free tissue transfer.
A review on the genetics of otosclerosis
Authors: Moumoulidis I. , Axon P. , Baguley D. , Reid E. 
Published: July 2007

Background:  The aetiology of otosclerosis is not fully understood despite intensive research. It is, however, certain that a genetic component plays a significant role in the manifestation of otosclerosis, although the precise mode of inheritance is still uncertain.Objective of review:  To provide an up‐to‐date review for the genetics of otosclerosis. The mode of inheritance, chromosomal and linkage studies are presented. In addition, the possible genetic relationship between otosclerosis and osteogenesis imperfecta, and the association between otosclerosis and specific human leucocyte antigen types are described.Type of review:  Systematic analysis of the literature was focused on any information related to the genetics of otosclerosis.Search strategy:  A MEDLINE search (1960–2007) was undertaken to perform a comprehensive review. Articles were also identified through searches of the files of authors.Results:  The majority of epidemiological studies on families with otosclerosis suggest an autosomal dominant mode of inheritance with reduced penetrance of approximately 40%. Genetic linkage studies have demonstrated the presence of six loci (OTSC1, OTSC2, OTSC3, OTSC4, OTSC5 and OTSC7) located on chromosomes 15q, 7q, 6p, 16q, 3q and 6q respectively. Although these loci have been mapped, no causative genes have been identified, and we have little idea of the molecular process involved in this disease. While clinical similarities and some unreplicated genetic association studies suggest an aetiological relationship between otosclerosis and osteogenesis imperfecta‐type I, there is no definite evidence of a common pathological process between the two diseases.Conclusions:  Otosclerosis may be considered as a complex disease with relatively common monogenic forms. Knowledge of these genes could lead to substantial improvements in our ability to diagnose and possibly even prevent or treat this type of hearing deterioration.
Interaction of specialist root and shoot herbivores of Alliaria petiolata and their impact on plant performance and reproduction
Authors: GERBER ESTHER , HINZ HARIET L. , BLOSSEY BERND 
Published: July 2007

Abstract 1. This study explored interactions of two spatially and temporally separated weevils and their impact on Alliaria petiolata (garlic mustard) survival, growth, and reproduction at different herbivore densities.2. The root‐mining weevil Ceutorhynchus scrobicollis attacks A. petiolata rosettes from October to April, and larvae complete development in May. The shoot‐mining weevil Ceutorhynchus alliariae attacks bolting plants in April/May with larvae completing development in June–July. Priority effects were expected, with early attack of C. scrobicollis affecting the later attacking C. alliariae, mediated through changes in plant growth or chemistry.3. Attack by C. scrobicollis significantly increased plant mortality and changed plant architecture, while C. alliariae only significantly reduced plant height. Attack by C. scrobicollis also increased nitrogen content of stems.4. Root feeding by C. scrobicollis affected the feeding niche of C. alliariae, but increased stem nitrogen content did not result in increased stem miner survival. While reduced height and stem diameters as a result of C. scrobicollis attack reduced C. alliariae attack at the stem level, attack at plant level and recruitment was unaffected.5. Weevil density had no effect on plant performance, most likely due to strong intraspecific competition, and there were no synergistic effects between the two herbivores.6. Overall, attack by C. scrobicollis was more detrimental to A. petiolata growth, seed output, and survival than attack by C. alliariae. Consequently, C. scrobicollis has been prioritised as a potential biocontrol agent for control of A. petiolata in North America.
Consequences for a host–parasitoid interaction of host‐plant aggregation, isolation, and phenology
Authors: VANBERGEN ADAM J. , JONES T. HEFIN , HAILS ROSIE S. , WATT ALLAN D. , ELSTON DAVID A. 
Published: July 2007

Abstract1. Spatial habitat structure can influence the likelihood of patch colonisation by dispersing individuals, and this likelihood may differ according to trophic position, potentially leading to a refuge from parasitism for hosts.2. Whether habitat patch size, isolation, and host‐plant heterogeneity differentially affected host and parasitoid abundance, and parasitism rates was tested using a tri‐trophic thistle–herbivore–parasitoid system.3. Cirsium palustrethistles (n= 240) were transplanted in 24 blocks replicated in two sites, creating a range of habitat patch sizes at increasing distance from a pre‐existing source population. Plant architecture and phenological stage were measured for each plant and the numbers of the herbivoreTephritis conuraand parasitoidPteromalus elevatusrecorded.4. Mean herbivore numbers per plant increased with host‐plant density per patch, but parasitoid numbers and parasitism rates were unaffected. Patch distance from the source population did not influence insect abundance or parasitism rates. Parasitoid abundance was positively correlated with host insect number, and parasitism rates were negatively density dependent. Host‐plant phenological stage was positively correlated with herbivore and parasitoid abundance, and parasitism rates at both patch and host‐plant scales.5. The differential response between herbivore and parasitoid to host‐plant density did not lead to a spatial refuge but may have contributed to the observed parasitism rates being negatively density dependent. Heterogeneity in patch quality, mediated by variation in host‐plant phenology, was more important than spatial habitat structure for both the herbivore and parasitoid populations, and for parasitism rates.
Male behaviour over the season in a wild population of the field cricket Gryllus campestris L.
Authors: RITZ MARKUS S. , KÖHLER GÜNTER 
Published: July 2007

Abstract 1. Cricket model systems have greatly enhanced our knowledge about mate choice and sexual selection. However, no studies exist that take seasonal dynamics into account and that follow individual males over the complete adult stage in the wild. In the present study, all adult field crickets (Gryllus campestris L.) were individually marked and measured in a population in central Germany and their behaviour was followed over their life from May to July 2000.2. The population reached a maximum of 108 males within 10 days and continuously declined thereafter. Daily mortality was positively correlated with burrow‐changing activity, which was highest at high mean temperatures. Median burrow occupation time was short at 1 day but males stayed up to 34 days in one burrow. Heavy males stayed longer in burrows and achieved a higher age.3.  Male displacement was on average 2.8 m per day and up to 284 m during their life. Displacement and lifespan were negatively correlated.4. Burrows were highly aggregated at the meadow in areas of vegetation cover <85%. Aggregation of males increased with advancing season and declining population size. Consequently, nearest‐neighbour distances remained stable at 5 m until the 50th day of the study.5. About half of the 159 detected matings occurred 4–6 h after sunrise. An increased mating frequency was observed between the 30th and 50th day after adult moult.
Predation of a cave fish (Poecilia mexicana, Poeciliidae) by a giant water‐bug (Belostoma, Belostomatidae) in a Mexican sulphur cave
Authors: TOBLER MICHAEL , SCHLUPP INGO , PLATH MARTIN 
Published: July 2007

Abstract 1. Caves are often assumed to be predator‐free environments for cave fishes. This has been proposed to be a potential benefit of colonising these otherwise harsh environments. In order to test this hypothesis, the predator–prey interaction of a belostomatid (predator) and a cave fish (prey) occurring in the Cueva del Azufre (Tabasco, Mexico) was investigated with two separate experiments.2. In one experiment, individual Belostoma were given a chance to prey on a cave fish, the cave form of the Atlantic molly (Poecilia mexicana), to estimate feeding rates and size‐specific prey preferences of the predator. In the other experiment, population density of Belostoma was estimated using a mark–recapture analysis in one of the cave chambers.3. Belostomatids were found to heavily prey on cave mollies and to exhibit a prey preference for large fish. The mark–recapture analysis revealed a high population density of the heteropterans in the cave.4. The absence of predators in caves is not a general habitat feature for cave fishes. None the less predation regimes differ strikingly between epigean and hypogean habitats. The prey preference of Belostoma indicates that cave‐dwelling P. mexicana experience size‐specific predation pressure comparable with surface populations, which may have implications for life‐history evolution in this cave fish.
Seasonality of spiders (Araneae) in Mediterranean ecosystems and its implications in the optimum sampling period
Authors: CARDOSO PEDRO , SILVA ISRAEL , DE OLIVEIRA NUNO G. , SERRANO ARTUR R. M. 
Published: July 2007

Abstract1. Fields such as ecology, macroecology, and conservation biology rely on accurate and comparable data. This is especially important for mostly unknown and megadiverse taxa such as spiders and regions such as the Mediterranean. Short‐term sampling programmes are increasingly seen as the best option for sampling spiders. Comparability of results, however, demands standard procedures both in methodology and in sampling period. Cost‐efficiency dictates that this period should be the most species rich.2. Pitfall trapping was conducted in 23 sites from north to south Portugal, comprising three large‐scale environmental zones and many different habitat types, during 10 months in each site. The annual richness pattern, differences in this pattern between areas and habitats, the complementarity between sampling periods and possible environmental correlates of richness were studied.3. May and June present the optimal time for collecting spiders in Mediterranean areas. Northern areas have a later peak in richness and dense tree‐cover sites offer more flexibility for sampling, with a higher proportion of species present at each period throughout the year.4. Day length is the environmental factor most correlated with species richness. Maximum daily temperature may reduce richness, especially in southernmost areas, where summer temperatures can be extremely harsh.5. It is recommended that short‐term sampling programmes, intended to give a reasonable picture of spider communities in Portugal and in the Iberian Peninsula (and possibly extending to all the Mediterranean), should be conducted during May or June, with variable flexibility according to area and habitat. The proposed suggestions should appeal to everyone working in the field, given the cost‐efficiency and comparability of results by adopting a common standardised approach.
Patterns of kleptoparasitism and inquilinism in social and non‐social Dunatothrips on Australian Acacia
Authors: BONO JEREMY M. 
Published: July 2007

Abstract 1. Australian Acacia thrips and their parasitic exploiters provide a novel system for analysing fundamental questions about host–parasite evolution and ecology.2. In this study, colony collections were used to examine interactions between members of the genus Dunatothrips and the diverse assemblage of parasitic thrips that invade domiciles constructed by the host on various species of Acacia.3. Dunatothrips parasites adopt a range of strategies for exploiting their hosts, including lethal fighting, host eviction, and cohabitation.4. Social Dunatothrips (D. aneurae and D. skene) were more frequently parasitised than non‐social D. gloius, which could be related to differences in social organisation or the fact that D. gloius has shifted onto a novel host that is distantly related to other Dunatothrips’ hosts.5. Parasitism rates of D. aneurae and D. skene domiciles were high (46% and 51% respectively), and were positively density dependent.