bluuebunny/crossref_metadata_2025 huggingface dataset:
Cell wall glucomannan in Arabidopsis is synthesised by CSLA glycosyltransferases, and influences the progression of embryogenesis
Authors: Goubet Florence , Barton Christopher J. , Mortimer Jennifer C. , Yu Xiaolan , Zhang Zhinong , Miles Godfrey P. , Richens Jenny , Liepman Aaron H. , Seffen Keith , Dupree Paul
Published: July 2009

Mannans are hemicellulosic polysaccharides that have previously been implicated as structural constituents of cell walls and as storage reserves but which may serve other functions during plant growth and development. Several members of the Arabidopsis cellulose synthase‐like A (CSLA) family have previously been shown to synthesise mannan polysaccharides in vitro when heterologously expressed. It has also been found that CSLA7 is essential for embryogenesis, suggesting a role for the CSLA7 product in development. To determine whether the CSLA proteins are responsible for glucomannan synthesis in vivo, we characterised insertion mutants in each of the nine Arabidopsis CSLA genes and several double and triple mutant combinations. csla9 mutants showed substantially reduced glucomannan, and triple csla2csla3csla9 mutants lacked detectable glucomannan in stems. Nevertheless, these mutants showed no alteration in stem development or strength. Overexpression of CSLA2, CSLA7 and CSLA9 increased the glucomannan content in stems. Increased glucomannan synthesis also caused defective embryogenesis, leading to delayed development and occasional embryo death. The embryo lethality of csla7 was complemented by overexpression of CSLA9, suggesting that the glucomannan products are similar. We conclude that CSLA2, CSLA3 and CSLA9 are responsible for the synthesis of all detectable glucomannan in Arabidopsis stems, and that CSLA7 synthesises glucomannan in embryos. These results are inconsistent with a substantial role for glucomannan in wall strength in Arabidopsis stems, but indicate that glucomannan levels affect embryogenesis. Together with earlier heterologous expression studies, the glucomannan deficiency observed in csla mutant plants demonstrates that the CSLA family encodes glucomannan synthases.
Resurrecting the differential mortality model of sexual size dimorphism
Authors: MAS E. DE , RIBERA C. , MOYA‐LARAÑO J.
Published: July 2009

In some animal groups males may be several times smaller than females. One of the hypotheses proposed to explain the evolution of this extreme sexual size dimorphism (SSD) is the differential mortality model (DMM), which is based on the assumption that when males are the searching sex, higher male mortality relaxes male–male contest competition, leading to the adaptive evolution of early‐maturing, small males that are favoured by viability selection. Evidence for the main prediction of this model, i.e. that there is a negative relationship between differential mortality and SSD, has remained elusive. Using sex differences in pitfall trap catches – a proxy of sex differences in mobility and mortality – across 40 spider species, and using the evolutionary comparative method, we found significant negative relationships between differential mortality and SSD for three size traits. Thus, the DMM can still explain part of the observed variance in SSD.
Development of elite indica rice lines with wide spectrum of resistance to Thai blast isolates by pyramiding multiple resistance QTLs
Authors: Sreewongchai T. , Toojinda T. , Thanintorn N. , Kosawang C. , Vanavichit A. , Tharreau D. , Sirithunya P.
Published: July 2009

With 1 figure and 2 tables

The rice varieties IR64 and Jao Hom Nin (JHN) demonstrated a broad‐spectrum resistance against the rice blast pathogens in Thailand. A genomic investigation unravelled many resistance genes residing on four genomic regions, chromosome 2 and 12 in IR64 and 1 and 11 in JHN. A cross between these varieties was made to combine resistance genes into a single genotype. Marker‐assisted selection (MAS) was employed to identify F2 and F3 plants carrying a combination of four resistance QTLs in a homozygous fusion. Flanking markers RM212/RM319 and RM144/RM139 to blast resistant QTLs on chromosome 1 and 11 in JHN rice and tightly‐linked markers RM208 and RM179 to blast resistant QTLs on chromosome 2 and 12 in IR64 rice variety were used for MAS. The stepwise MAS screening was brought in as a strategy to provide a cost‐saving and minimum number of PCR performing to select resistant genotypes. F4 generation, lines carrying all resistant QTLs show a broader spectrum of resistance against 11 representatives of Thai blast pathogen isolates.
Meiotic behaviour in the first interspecific hybrids between Brachiaria brizantha and Brachiaria decumbens
Authors: De Souza‐Kaneshima A. M. , Simioni C. , Felismino M. F. , Mendes‐Bonato A. B. , Risso‐Pascotto C. , Pessim C. , Pagliarini M. S. , Do Valle C. B.
Published: July 2009

With 2 figures and 1 table

Brachiaria brizantha and Brachiaria decumbens constitute the two most widely used tropical forage species for cultivated pastures and support both beef and dairy cattle production in the tropics. Two apomictic cultivars –B. brizantha cv. ‘Marandu’ and B. decumbens cv. ‘Basilisk’– cover more than 100 million hectares of cultivated pastures throughout Latin America and Southeast Asia. This paper discusses the cytogenetic data of the first successful attempt in obtaining interspecific hybrids between these two species. Artificial hybridization between two diploid (2n = 2x = 18) sexual accessions (B. brizantha, B105 × B. decumbens, D004) was performed in the greenhouse. Only three hybrids were recovered. One of them was treated with colchicine in tissue culture and two amphidiploid plants were obtained. Meiosis in the diploid genitors was quite normal, while in the diploid hybrid parental genome separation was observed together with some irregular chromosome segregation. Genome separation was also observed in several cells in the two 4n amphidiploid hybrids. In these, a high number of meiocytes with chromosomes chaotically spread in the cytoplasm was recorded during meiosis. The abnormalities observed compromised the meiotic products characterized by polyads. Chromosomes associated generally as bivalents but some association as quadrivalents in diakinesis in one of the amphidiploid hybrids indicates taxonomic proximity between these two species. Moreover, it indicates that introgression of desirable genes may be feasible between these two most important agronomic species of the genus.
Genetic analysis of adult plant resistance to Puccinia hordei in barley
Authors: Golegaonkar P. G. , Park R. F. , Singh D.
Published: July 2009

With 2 figures and 5 tables

Genetic studies were conducted to determine the number of genes conferring adult plant resistance (APR) to Puccinia hordei in eight barley genotypes and to determine their relationship with each other. Field testing of segregating populations at two field sites indicated that the genotypes ‘Vada’, ‘Nagrad’, ‘Gilbert’ and ‘WI3407’ each carried one gene for APR to leaf rust. Genotypes ‘Patty’, ‘Pompadour’‘Athos’ and ‘RAH1995’ showed digenic inheritance of APR at one field site and monogenic inheritance at the second. One of the genes identified in each cultivar provided high levels of APR and was effective at both field sites. The second APR gene was effective only at one field site, and it conferred low levels of APR. Tests of allelism between resistant genotypes confirmed a common APR gene in all with the exception of ‘WI3407’, which was genetically distinct from the gene common in ‘Vada’, ‘Nagrad’, ‘Patty’ and ‘Pompadour’.
Combined assessment of chronic kidney disease and subclinical peripheral artery disease used to predict future cardiac events
Authors: ITAYA HIDEKI , SHIBA MASANORI , JOKI NOBUHIKO , NAKAMURA MASATO
Published: July 2009

Background:  Both the presence of peripheral arterial disease and chronic kidney disease has been reported to be independent risk factors associating with poor prognosis. However, the impact of combination of peripheral arterial disease and chronic kidney disease remains unknown.

Methods:  The long‐term outcome in 715 consecutive patients who had undergone coronary angiogram for the evaluation of chest pain was analyzed. Patients on haemodialysis were excluded from this analysis. Cohort patients were divided into four groups according to the Ankle Brachial Index (ABI <0.9) and glomerular filtration rate (GFR <60 mL/min per m2): group A (n= 498; ABI >0.9, GFR >60); B (n = 65, ABI <0.9, GFR >60); C (n = 99; ABI >0.9, GFR <60); and D (n = 53; ABI <0.9, GFR <60). The mean follow‐up period was 620 ± 270 days and evaluated the major cardiac adverse events included survival, stroke, acute coronary syndrome and heart failure.

Results:  The mean follow‐up period was 620 ± 270 days. Total long‐term event was present in 89 patients (groups A–D were 9.4%, 18.5%, 15.2% and 28.3%, respectively). Long‐term event rate was 28.3% for patients with the presence of peripheral arterial disease and chronic kidney disease, compared to 9.4% for those without peripheral arterial disease and chronic kidney disease (P < 0.0001). Kaplan–Meier event‐free survival curves also showed that the combination of peripheral arterial disease and chronic kidney disease predicted long‐term event rate.

Conclusion:  The combination of chronic kidney disease and ABI of less than 0.9 undergoing coronary angiogram is strongly associated with long‐term event rate.
Irritable bowel syndrome in haemodialysis: Prevalence, link with quality of life and depression
Authors: AFSAR BARIS , ELSURER RENGIN , YILMAZ M ILKER , EYILETEN TAYFUN , YENICESU MÜJDAT
Published: July 2009

Aim:  Health‐related quality of life (HRQOL) is decreased in haemodialysis (HD) patients. Irritable bowel syndrome (IBS) is highly prevalent in general population. This study evaluated the prevalence of IBS and its association with HRQOL and depression in HD.

Methods:  Sociodemographic and laboratory variables were recorded. Severity of depressive symptoms and HRQOL were assessed by the Beck Depression Inventory (BDI) and Short Form 36 (SF‐36), respectively. Diagnosis of IBS was based on Rome II criteria.

Results:  Among 236 patients 69 (29.2%) had IBS. Patients with IBS had lower SF‐36 scores and had higher depressive symptoms than patients without IBS. Presence of IBS was associated with sleep disturbance (odds ratio (OR) = 2.012; P = 0.045), physical component summary score (OR = 0.963, P = 0.029), mental component summary score (OR = 0.962, P = 0.023), BDI score (OR = 1.040, P = 0.021) and albumin (OR = 0.437, P = 0.01).

Conclusion:  IBS is highly prevalent in HD patients. Presence of IBS is closely related with HRQOL and depression.
Opinions on the content and effects of the Caring for Australasians with Renal Impairment (CARI) Guidelines: A survey of renal nurses and comparison with the opinions of nephrologists in Australasia
Authors: IRVING MICHELLE J , JOHNSON DAVID W , MCDONALD STEPHEN , WALKER ROWAN G , FROMMER MICHAEL S , FETHERSTONHAUGH DEIRDRE , DEANS PAMELA , CRAIG JONATHAN C
Published: July 2009

Aim:  Renal nurses in Australia and New Zealand are critical to the care of patients with chronic kidney disease (CKD), especially those on dialysis. We aimed to obtain the opinions of renal nurses in Australia and New Zealand on the Caring for Australasians with Renal Impairment (CARI) Guidelines.

Methods:  A self‐administered survey was distributed to all members of the professional organisation for renal nurses (Renal Society of Australasia) in 2006. The results were compared with those from a similar survey in 2002 and an identical 2006 survey of Australian and New Zealand nephrologists.

Results:  Of the 173 respondents, more than 95% considered the Guidelines to be a good synthesis of the available evidence, 80% indicated that the Guidelines had significantly influenced their practice and 86% considered that the Guidelines had improved patient outcomes. Older respondents were less likely to perceive that the Guidelines had improved patient outcomes, and renal nurse educators were more likely to consider that the Guidelines were based on the best available evidence than other respondents. Respondents were generally more positive about the Guidelines in 2006 than in 2002. Although nephrologists were generally positive about the CARI Guidelines, renal nurses were more positive, especially regarding the effect of the Guidelines on practice and the improvement in health outcomes.

Conclusion:  Australian and New Zealand renal nurses valued the CARI Guidelines highly, used them in practice and considered that they led to improved patient outcomes. Positive responses towards the Guidelines increased between 2002 and 2006.
Work satisfaction of Japanese public health nurses: Assessing validity and reliability of a scale
Authors: Yamashita Mineko , Takase Miyuki , Wakabayshi Chihiro , Kuroda Kaori , Owatari Nozomi
Published: July 2009

The Index of Work Satisfaction, developed by Stamps et al., was administered to 583 nurses who had practiced public health nursing in Japan. After psychometric evaluation, three components were identified as contributing to their job satisfaction: the work environment, professional confidence, and commitment to the profession. Overall, the participants in the study were quite satisfied. The findings corroborated previous reports on Japanese nurses' job satisfaction, in that the nurses in the study were most satisfied with their relationships with peers, patients/families, and supervisors. However, they were least satisfied with having enough time for client care, having confidence, and promotion opportunities. The implications are discussed, to the effect that understanding the factors related to public health nurses' job satisfaction could help administrators to improve regulations and other issues related to the work environment.
Caregiver suctioning education for Japanese patients with an invasive home ventilator
Authors: Imaiso Junko , Yamauchi Toyoaki
Published: July 2009

In Japan, more people require care activities at home. In particular, patients with an invasive mechanical ventilator in the home require extensive care by family caregivers. Collaboration between their nurses and paid caregivers in the provision of care activities, especially tracheal suctioning, is necessary. This three‐round Delphi study identifies the essential items required by nurses to instruct the paid caregivers in how to carry out tracheal suctioning on patients with an invasive mechanical ventilator in the home. By the final round, three competencies were found to be important by the home‐visit nurses and paid caregivers: the anticipation of risk, the manner of handling an emergency situation, and the observation of a patient's breathing. The Delphi technique was used to obtain consensus between the home‐visit nurses and the paid caregivers regarding the essential knowledge, skills, and attitudes required to carry out tracheal suctioning for patients with an invasive mechanical ventilator in the home.
Habitat protection, cattle grazing and density‐dependent reproduction in a desert tree
Authors: ASCHERO VALERIA , VÁZQUEZ DIEGO P.
Published: July 2009

Anthropogenic activities usually trigger changes in the population density of plants. Thus, land management practices can influence density‐dependent demographic parameters and species interactions. We investigated plant‐pollinator interactions and reproduction in Prosopis flexuosa, the largest tree species in the Central Monte desert of Argentina, an important economic and cultural resource for humans and a functionally prominent species. We hypothesized that reproductive output of P. flexuosa would be limited at low densities, and that exclusion of catle grazing would enhance population density and consequently interaction frequency with pollinators and reproductive success. The study was conducted in and around Ñacuñán Biosphere Reserve (Mendoza, Argentina), where cattle grazing has been excluded for over 35 years. Working in five pairs of protected and cattle grazed 1‐ha plots, we recorded density of adult trees, pollinator visitation frequency to inflorescences and seeds per inflorescence in focal trees. Adult tree density was higher in protected plots than in cattle grazed plots. Density of reproductive trees was positively correlated with seed production, suggesting positive density dependence for reproduction (Allee effect). Pollinator visitation to inflorescences and seed production was higher in protected plots compared with plots under cattle grazing. Suppression of anthropogenic degradation has resulted in higher adult tree density in protected plots, indirectly higher pollinator visitation to inflorescences and higher reproductive success of trees. Increased frequency of plant‐pollinator interactions and tree reproduction suggest success of management practices aimed at protecting P. flexuosa woodlands.
Biogeography of Australian saltmarsh plants
Authors: SAINTILAN NEIL
Published: July 2009

The paper seeks to define patterns in the distribution of Australian saltmarsh plants over a continental scale, and test for associations with environmental variables. The distribution of 93 species of Australian saltmarsh plants was documented from the records of the Australian Virtual Herbarium and published reports. The Interim Bioregionalisation of Australia provided a spatial unit for the analysis of patterns of diversity. Saltmarsh diversity was shown to be strongly correlated with latitude and temperature. Multivariate routines including cluster analysis demonstrated consistent geographic patterns in species assemblages. The primary distinction was found to be a north‐south divide dissecting the continent at the latitude of 23° south, separating a species‐rich southern flora from a species‐poor northern flora. Subsequent dissimilarities were defined between coastlines of contrasting orientation. Mean minimum temperature was found to explain nearly 80% of variability in saltmarsh species diversity between bioregions, with diversity inversely related to temperature.
Within‐population variation in social strategies characterize the social and mating system of an Australian lizard,Egernia whitii
Authors: WHILE GEOFFREY M. , ULLER TOBIAS , WAPSTRA ERIK
Published: July 2009

The lizard genusEgerniahas been suggested as an excellent model system for examining the evolution of sociality as it exhibits considerable diversity in social organization both between and within species. To date the majority of work examining the factors responsible for the evolution of sociality withinEgerniahas advocated a broad scale approach; identifying the social structure of specific species or populations and comparing the degree of sociality between them. However, we argue that significant advancements could also be gained by examining variation in social strategies within populations. Here we integrate a detailed, 3‐year, field‐based examination of social spacing and juvenile dispersal with molecular analyses of paternity to determine the social and mating system of a Tasmanian population of White's skink (Egernia whitii). We show thatE. whitiilive in small stable family groups consisting of an adult male, his female partner(s), as well as juvenile or sub‐adults individuals. In addition, while the mating system is characterized by considerable genetic monogamy, extra‐pair fertilizations are relatively common, with 34% of litters containing offspring sired by males from outside the social group. We also show that traits related to social organization (social group composition, group size, stability and the level of extra‐pair paternity) vary both between and within individuals. We suggest that ecological factors, such as habitat saturation, quality and availability, play a key role in maintaining between individual variation in social strategies, and that examining these individual level processes will allow us to more clearly understand variation in sociality among species.
Few beetle species can be detected with 95% confidence using pitfall traps
Authors: DRISCOLL DON A.
Published: July 2009

False absences in wildlife surveys make it difficult to identify metapopulation processes, increase uncertainty of management decisions and bias parameter estimates in habitat models. Despite these risks, the number of species that can be detected with a certain probability in a community survey has rarely been examined. I sampled beetles over 5 months using pitfall trap grids at three rainforest locations in Tasmania, Australia. I compared detection probability for dispersed and clustered sampling schemes using a zero‐inflated binomial model and a simpler occurrence method to calculate the probability of detection. After excluding extremely rare species, I analysed 12 of 121 species. Only three to six species could be detected with 95% probability using a sampling effort that is frequently applied in ecological studies. A majority of common species had a mid summer peak in detection probability meaning that survey effort could be reduced from 5 to 2 months with only a small reduction in data quality. Most species occurred at only a proportion of sample points within locations. Despite the implied spatial structuring, three small grids within a location detected 10 of 12 species as effectively as large, dispersed grids. This study warns that as little as 5% of the beetle fauna may have a 95% probability of detection using the frequently applied pitfall trap method, highlighting a substantial limitation in our ability to accurately map the distributions of ground invertebrates. Whether very large sample sizes can overcome this limitation remains to be examined.
Partitioning of temporal activity among desert lizards in relation to prey availability and temperature
Authors: GORDON CHRISTOPHER E. , DICKMAN CHRIS R. , THOMPSON MICHAEL B.
Published: July 2009

Partitioning of activity time within ecological communities potentially reduces interspecific competition and increases the number of species that can coexist. We investigated temporal activity in a highly diverse lizard assemblage in the Simpson Desert, central Australia, to determine the degree of partitioning that occurs. Three periods were defined, daytime (sunrise to sunset), early night (sunset to midnight) and late night (midnight to sunrise), and live captures of lizards were tallied for each period during two sampling months (September and November 2007). We also quantified the activity times of potential invertebrate prey and measured ambient temperatures during the different time periods to investigate any associations between these factors and lizard activity. Some 77% of captures of 13 lizard species were made by day, with Ctenotus pantherinus, Egernia inornata (Scincidae) and Nephrurus levis (Gekkonidae) the only species showing extended nocturnal activity. Activity of both species of skink was recorded at temperatures 4°C lower than those for agamid and varanid lizards early in the night, and at temperatures as low as 18–20°C. Surface‐active invertebrates differed in composition between time periods and were less abundant during the late night period in the drier of the two sample months (September), but were distributed equally over time in the other month. Termites were active in subterranean galleries at night in September and mostly by day in November, but available at all times on surface/subsurface baits. We conclude that activity is distributed unevenly within this lizard assemblage, with partitioning facilitated by the ready availability of invertebrate prey and by lizards having relatively broad temperature tolerances that, in some cases, permit opportunistic exploitation of resources beyond usual times of activity.
Resolving the differences in plant burial responses
Authors: GILBERT MATTHEW E. , RIPLEY BRAD S.
Published: July 2009

Burial is one of the major factors influencing plant ecology in deserts and coastal areas. Consequently, many studies have measured the responses of dune plants to sand burial. However, there remains little agreement about the mechanisms and characteristics constituting the burial response of plants. In particular, stimulation of growth has been reported as the most common plant burial response; however, stimulation has not been reported consistently among studies. Here, a literature survey showed that the depth of burial relative to the height of the plant determined whether the growth of a species was stimulated by burial. Growth stimulation was limited to shallow burial depths, while burial depths greater than the height of the plant consistently resulted in reduced growth. As studies used widely differing burial depths or units of growth measurement, the variation in reported stimulation of plant growth can be partly attributed to differences in experimental procedure. The stimulation of growth in many species was accompanied by an increase in photosynthesis over a limited period and by a shift in biomass allocation from root to shoot. Most plants demonstrated stimulated growth (up to 200%) in response to shallow burial indicating that some burial response mechanisms are general to many species. However, a few specialist dune species displayed a much greater ability to respond to burial (up to 700% stimulation of plant mass). Although allocation shifts and increased photosynthesis have been shown to be associated with dune plant burial response, there remains a need for field measurements that focus on the diversity of mechanisms underlying plant response to burial.
Spatial distribution and prediction of seed production by Eucalyptus microcarpa in a fragmented landscape
Authors: VESK PETER A. , DAVIDSON ANTHONY , CHEE YUNG EN
Published: July 2009

Woodlands worldwide have been greatly modified by clearing for agriculture, and their conservation and restoration requires understanding of tree recruitment processes. Seed production is one possible point of recruitment failure, and one that the spatial arrangement of trees may affect. We sampled 118 Eucalyptus microcarpa (Myrtaceae) trees to compare and analyse the determinants of seed production in this dominant tree of modified, fragmented temperate grassy woodlands, which extend over much of southeastern Australia. Fecundity was estimated as the seed crop measured on leaf mass and whole tree bases and was compared between categories of tree configuration. We also modelled fecundity using boosted regression trees, a new and flexible tool. Fecundity on a leaf mass basis was predominantly influenced by environmental factors (topographic ‘wetness’, slope, soil type), rather than by local tree density and configuration. Fewer seed per unit leaf mass were produced on flat and topographically wet sites, reflecting poor tolerance of waterlogging by E. microcarpa. By contrast, whole tree fecundity was little influenced by environmental factors. Local tree density and configuration did influence whole tree fecundity, which was high in solitary and woodland‐spaced trees and reduced under high local density. We found little evidence for reduced fecundity of E. microcarpa in solitary trees. This points to the importance of scattered trees as sources of seed for tree recruitment and for natural regeneration of landscape level tree cover. Considerable uncertainty remains in modelled seed supply, and may be reduced with sampling across multiple years and greater environmental and spatial domains.
Measuring the effectiveness of regional conservation assessments at representing biodiversity surrogates at a local scale: A case study in Réunion Island (Indian Ocean)
Authors: PAYET KARINE , ROUGET MATHIEU , LAGABRIELLE ERWANN , ESLER KAREN J.
Published: July 2009

In a context of scarce financial and human resources, the allocation of conservation efforts needs to be optimized. Our analysis attempts to draw conclusions on the integration of regional and local conservation assessments, specifically, with regard to the acquisition of fine‐scale data to complement the regional assessment. This study undertaken in Réunion Island (Indian Ocean) assessed how biodiversity surrogates targeted at a regional scale represented other biodiversity surrogates at a local scale. Biodiversity surrogates at both scales consisted of species, habitats and processes. Habitats and processes at regional scale were defined using a coarser scale of thematic resolution than at local scale. The surrogacy was tested in terms of incidental representation of local‐scale features in the regional assessments, and correlation of irreplaceability values between scales. Near‐minimum sets and irreplaceability values were generated using MARXAN software. Our results revealed that conservation targets for processes at local scale were never met incidentally, while threatened species and fragmented habitats were also usually under‐represented. More specifically, requiring only 12% of the local planning domain, the application of species as surrogates at regional scale was the least effective option at representing biodiversity features at local scale. In contrast, habitats at a coarse scale of thematic resolution achieved a significant proportion of conservation targets incidentally (67%) and their irreplaceability values were well correlated with the irreplaceability values of surrogates at local scale. The results highlighted that all three types of biodiversity surrogates are complementary for assessing overall biodiversity. Because of the cost of data acquisition, we recommended that the most efficient strategy to develop nested regional/local conservation plans is to apply habitats and processes at a coarse scale of thematic resolution at regional scale, and threatened species and degraded habitats at local scale, with their fine‐scale mapping limited to highly transformed areas.
Belly up: Reduced crevice accessibility as a cost of reproduction caused by increased girth in a rock‐using lizard
Authors: SCHWARZKOPF LIN , BARNES MEGAN , GOODMAN BRETT
Published: July 2009

Costs of reproduction are any aspect of current reproduction that has the potential to reduce survivorship or reproductive output, and may include physiological costs or increased risks. Females of many species experience increased body mass, and increased girth, when gravid. Increased body mass reduces running speed and increases the cost of locomotion during pregnancy, but few studies have examined the cost of increased girth. If increased girth of gravid females reduces access to shelter from predators or the elements, increased girth could constitute a cost of reproduction. In the laboratory, we experimentally tested whether access to crevices was limited in viviparous, saxicolous female lizards (Eulamprus brachysoma), which use crevices for shelter, by measuring access to artificial crevices of known widths, and body height during and after pregnancy. Gravid E. brachysoma had significantly greater body height (11.2% on average), and as a result were forced to use significantly wider crevices (18.4% wider on average) than post‐parturition. Females with larger clutch sizes had wider mid‐bodies and required larger crevices. Control females, which were not gravid at either time of testing, showed no significant change in the size of crevice they could enter over time. If access to narrow crevices provides advantages such as protection from predators, or is important for thermoregulation, then gravid females may suffer a cost of reproduction because their access to narrower crevices is limited.
Pediatric DNAR orders in the perioperative period
Authors: STACK CHARLES G. , PERRING JEFF
Published: July 2009

Do not attempt resuscitation (DNAR) orders are a formal expression of the intention to refrain from resuscitation. Since their inception in 1974, such orders have become widely accepted within the hospital setting. However, their acceptance in theatres where anesthesia may cause cardiovascular instability, outcomes from cardiac arrest are improved and when there is a cross‐over of techniques between anesthetic practice and resuscitation, has been more problematic.

In order to ascertain the opinions on DNAR orders in the perioperative period, a questionnaire was sent to all consultant members of the Association of Paediatric Anaesthetists of Great Britain and Ireland, which asked about DNAR orders, resuscitation under anesthesia and included a number of case studies. Of the 280 respondents, 160 (57.1%) agreed that an anesthetist could alter the order in the perioperative period with 41 (14.6%) stating that they would always suspend such an order. Most anesthetists agreed that they would discuss DNAR orders during their preoperative assessment but could not agree as to which interventions constituted normal anesthetic practice as opposed to resuscitation.

At present, there is variation in practice between pediatric anesthetists over suspension of DNAR orders in the perioperative period and no specific guidelines to refer to. We suggest that guidelines be produced and that these should take into account the work that has already taken place and guidelines published by other anesthetic communities.
Diagnosis of Hirschsprung’s Disease: an age‐related approach in children below or above one year
Authors: Noviello C. , Cobellis G. , Romano M. , Amici G. , Martino A.
Published: July 2009

Aim  The aim of this study was to evaluate the effectiveness of a differential diagnostic approach to Hirshchsprung’s Disease (HD) on the basis of age.

Method  Data on 185 consecutive children with suspected HD were subjected to an age‐related diagnostic approach. The patients were divided into two groups according to age (A < 1 year; B > 1 year). Children in Group A had rectal suction biopsy (RSB) and contrast enema (CE), and in Group B anorectal manometry (ARM) was performed. Patients with a normal recto‐anal inhibitory reflex (RAIR) underwent bowel disimpaction and medical treatment. Only selected cases in Group B underwent RSB and CE.

Results  In Group A (18 patients) CE showed a colonic transitional zone in three patients, whereas RSB led to the diagnosis of HD in nine. In Group B (167 patients) ARM was not possible in seven patients and it was normal in 140 (normal anal sphincter pressure: 83; hypertonia of the internal anal sphincter: 57). The RAIR was negative in 20 patients. RSB performed in 31 children in Group B confirmed HD in three patients.

Conclusions  For patients with a neonatal onset of constipation RSB is the best diagnostic technique. Chronic constipation is rarely due to HD and ARM is a useful non‐invasive screening tool.
Comparison of vildagliptin and thiazolidinedione as add‐on therapy in patients inadequately controlled with metformin: results of the GALIANT trial – a primary care, type 2 diabetes study
Authors: Blonde L. , Dagogo‐Jack S. , Banerji M. A. , Pratley R. E. , Marcellari A. , Braceras R. , Purkayastha D. , Baron M.
Published: July 2009

Aim: To assess the efficacy and tolerability of vildagliptin compared with thiazolidinediones (TZDs) as an add on to metformin treatment in a primary care patient population with type 2 diabetes.

Methods: This was a randomized, 12‐week, open‐label study comparing vildagliptin (100 mg, n = 1653) and TZD (agent and dose at the investigators’ discretion, n = 825) add‐on therapy in patients inadequately controlled [haemoglobin A1C (HbA1c): 7–10%] on a stable dose of metformin (≥1000 mg/day). The primary objective was to test non‐inferiority of vildagliptin to TZDs for the difference in change in HbA1c from baseline [established if the upper limit of the two‐sided 95% confidence intervals (CI) did not exceed 0.4%].

Results: Mean (± s.e.) change in HbA1c from baseline to study endpoint was –0.68 ± 0.02% in the vildagliptin group and −0.57 ± 0.03% in the TZD group. The difference between groups was −0.11% (95% CI: −0.17% and −0.04%), establishing the non‐inferiority of vildagliptin (p = 0.001) after 3 months of treatment. Vildagliptin was non‐inferior to TZDs for subgroups of race, age and body mass index. Body weight increased in the TZD group (0.33 ± 0.11 kg) and decreased in the vildagliptin group (mean: −0.58 ± 0.09 kg; p < 0.001 for difference). Adverse events occurred in similar proportions of patients in both groups (vildagliptin: 39.5% and TZD: 36.3%) Hypoglycaemia and abnormal changes in liver enzymes were uncommon.

Conclusions: This short‐term study suggests that vildagliptin is as effective as TZDs after 3‐month treatment as an add‐on to metformin in a primary care population that included diverse patient subgroups.
Dissociated incretin response to oral glucose at 1 year after restrictive vs. malabsorptive bariatric surgery
Authors: Guldstrand M. , Ahrén B. , Näslund E. , Holst J. J. , Adamson U.
Published: July 2009

Aim: Compare the response to oral glucose of the two incretin hormones, glucose‐dependent insulinotropic polypeptide (GIP) and glucagon‐like peptide‐1 (GLP‐1) at 1 year after restrictive vs. malabsorptive bariatric surgery.

Methods: Vertical banded gastroplasty (VBG, n = 7) or jejunoileal bypass (JIB, n = 5) was performed in 12 women, aged 26–39 years, with severe obesity [body mass index (BMI) 46.6 ± 2.3 kg/m2]. After 1 year, 75 g glucose was administered and plasma levels of glucose, insulin, GIP and GLP‐1 were determined regularly during the following 2 h.

Results: At 1 year after operation, reduction in body weight, actual body weight, fasting glucose or insulin, or the glucose and insulin responses to oral glucose did not differ significantly between the groups. Similarly, fasting GIP and GLP‐1 levels did not differ significantly between the groups. In contrast, the GIP and GLP‐1 responses to oral glucose were different between the groups in a dissociated pattern. Thus, AUCGIP was significantly higher after VBG than after JIB (53 ± 8 vs. 26 ± 6 pmol/l/min, p = 0.003). In contrast, AUCGLP−1 was significantly higher after JIB than after VBG (49 ± 5 vs. 20 ± 3 pmol/l/min, p = 0.007).

Conclusions: We conclude that at 1 year after bariatric surgery, the two incretins show dissociated responses in that the GIP secretion is higher after VBG whereas GLP‐1 secretion is higher after JIB. This dissociated incretin response is independent from reduction in body weight, glucose tolerance or insulin secretion.
State‐conditional Fertilizer Yield Response on Western Kenyan Farms
Authors: Marenya Paswel P. , Barrett Christopher B.
Published: July 2009

Fertilizer interventions have attained prominence in rural poverty reduction programs in Africa. Using data from maize plots operated by small farmers in western Kenya, we find a von Liebig‐type relationship between soil organic matter (SOM) and maize yield response to nitrogen application. Low SOM commonly limits the yield response to mineral fertilizer application. Although fertilizer is, on average, profitable in our sample, on roughly one‐third of the plots degraded soils limit the marginal productivity of fertilizer such that it becomes unprofitable at prevailing prices. Moreover, because poorer farmers most commonly cultivate soils deficient in SOM, fertilizer interventions might be less pro‐poor than is widely assumed and may instead reinforce ex ante income inequality.
Consumer and Market Responses to Mad Cow Disease
Authors: Schlenker Wolfram , Villas‐Boas Sofia B.
Published: July 2009

We examine how consumers and financial markets in the United States reacted to two health warnings about mad cow disease: the first discovery of an infected cow in December 2003 and an Oprah Winfrey show that aired seven years earlier on the potentially harmful effects of mad cow disease. We find a pronounced and significant reduction in beef sales following the first discovery of an infected cow in a product‐level scanner data set of a national grocery chain. Cattle futures show a pattern of abnormal price drops comparable to the scanner data. Contracts with longer maturity show smaller drops, suggesting that the market anticipated the impact to be transitory. Cattle futures show abnormal price drops after the Oprah Winfrey show that are more than 50% of the drop following the 2003 discovery of an infected cow.
Finding Missing Markets (and a Disturbing Epilogue): Evidence from an Export Crop Adoption and Marketing Intervention in Kenya
Authors: Ashraf Nava , Giné Xavier , Karlan Dean
Published: July 2009

Farmers may grow crops for local consumption despite more profitable export options. DrumNet, a Kenyan NGO that helps small farmers adopt and market export crops, conducted a randomized trial to evaluate its impact. DrumNet services increased production of export crops and lowered marketing costs, leading to a 32% income gain for new adopters. The services collapsed one year later when the exporter stopped buying from DrumNet because farmers could not meet new EU production requirements. Farmers sold to other middlemen and defaulted on their loans from DrumNet. Such experiences may explain why farmers are less likely to adopt export crops.
Export Sectors and Rural Development
Authors: Kilkenny Maureen , Partridge Mark D.
Published: July 2009

The export base hypothesis is that a region's growth is led by export demand, given perfectly elastic factor supplies. It is a rationale for “sector‐based” rural development policies, and it is formalized by input‐output models. But it is contested by modern trade, migration, and growth theories, and there is little research about its empirical relevance. We investigate the hypothesis for contemporary U.S. rural development by estimating the influence of export sector employment on subsequent rural development outcomes. The results reject the hypothesis that emphasizing traditional export employment results in rural growth, reject the assumption of perfectly elastic factor supply, and support alternative explanations.
Farmers’ Subjective Valuation of Subsistence Crops: The Case of Traditional Maize in Mexico
Authors: Arslan Aslihan , Taylor J. Edward
Published: July 2009

Shadow prices guide farmers’ resource allocations, but for subsistence farmers who grow traditional crops they may bear little relationship with market prices. We theoretically derive shadow prices for a subsistence crop with nonmarket value, then estimate shadow prices of maize using data from a nationally representative survey of rural households in Mexico. Shadow prices are significantly higher than market prices for traditional but not improved maize varieties. They are particularly high in the indigenous areas of southern and southeastern Mexico, indicating large de facto incentives to maintain traditional varieties there.
The Impact of Agricultural Extension and Roads on Poverty and Consumption Growth in Fifteen Ethiopian Villages
Authors: Dercon Stefan , Gilligan Daniel O. , Hoddinott John , Woldehanna Tassew
Published: July 2009

This article investigates whether public investments that led to improvements in road quality and increased access to agricultural extension services led to faster consumption growth and lower rates of poverty in rural Ethiopia. Estimating an Instrumental Variables model using Generalized Methods of Moments and controlling for household fixed effects, we find evidence of positive impacts with meaningful magnitudes. Receiving at least one extension visit reduces headcount poverty by 9.8 percentage points and increases consumption growth by 7.1 percentage points. Access to all‐weather roads reduces poverty by 6.9 percentage points and increases consumption growth by 16.3 percentage points. These results are robust to changes in model specification and estimation methods.
‘They're telling me what I already know instead of what I don't know’: dyslexic pupils' experiences of withdrawal tuition during the later primary years
Authors: ANDERSON ROSEMARY
Published: July 2009

This article reports findings from a qualitative case study whose main focus was on how four 10–11‐year‐old dyslexic pupils coped with the demands of classroom reading during their final two years (Years 5–6) at a primary school in the north of England. Data were also collected on more general issues associated with the pupils' experiences of small‐group withdrawal tuition, and it is this evidence that is drawn on here. Although there were some benefits in terms of improved self‐esteem and overall confidence levels, problems with the sessions were revealed. The work on basic literacy skills lacked challenge as it was not well matched to learning needs and disaffection was created due to missing class lessons. Because of their literacy difficulties these dyslexic pupils were inevitably marginalised within the classroom community of learners, and I argue that attending withdrawal sessions added to their exclusionary experience of school.
Tarzan helps to find dyslexics: a pseudo‐word test
Authors: TAKALA MARJATTA , KUUSELA JORMA
Published: July 2009

A pseudo‐word test called Tarzan will be presented and standard scores for high school‐aged students between 16 and 18 will be suggested. The test uses E. R. Burroughs' text, in which pseudo‐words are added in order to study phonological coding and, through that, possible dyslexia. Girls performed better on the test and their scores correlated well with existing standardised tests. The test is easy and quick to perform and can be a tool for teachers when diagnosing reading problems. However, it cannot be used alone; several and diverse tests are needed.
CRIME IN A MULTI‐JURISDICTIONAL MODEL WITH PRIVATE AND PUBLIC PREVENTION*
Authors: Lee Kangoh , Pinto Santiago M.
Published: July 2009

ABSTRACT Criminals move between jurisdictions in response to differences in the net returns to crime that depend on the opportunity for crime and the effort to prevent crime. An increase in police protection of a jurisdiction diverts crime to other jurisdictions when only public crime prevention such as police protection is available. However, residents also invest in private prevention (private security, burglar alarms, etc.), and the value of these measures depends on the level of local public protection. In a spatial context, an increase in public prevention of a jurisdiction not only alters the incentives of individuals of the jurisdiction, but also of other jurisdictions as well, and such a change in private crime prevention may end up attracting crime to the jurisdiction. An increase in public prevention of a jurisdiction thus may divert or attract crime. This ambiguous effect stands in contrast with the literature and may appear counterintuitive, but is logical under plausible conditions.
Growth rate as a prognostic factor in localized invasive cutaneous melanoma
Authors: Tejera‐Vaquerizo A , Barrera‐Vigo MV , López‐Navarro N , Herrera‐Ceballos E
Published: July 2009

Background  Melanoma is a tumour with a very variable progression. Whilst some melanomas grow slowly over many years, others can reach several millimetres in thickness in just a few weeks. Since melanoma is a visible superficial tumour, the information obtained from the clinical interview may be of use to calculate the speed of growth of the melanoma.

Objective  This study aims to assess the growth rate (GR) of melanomas and the association of this GR with various clinical and pathological factors and their usefulness as prognostic markers for localized invasive cutaneous melanomas.

Methods  The GR of melanomas was calculated as the ratio of tumour thickness to time of development, as obtained from the clinical history (in millimetres per month).

Results  Applying the GR calculation to patients with a localized melanoma showed a significant association between melanomas with a GR greater than 0.4 mm per month and an age of 65 years or over, male sex, nodular melanoma, tumour thickness, level of invasion, the presence of ulceration and a high mitotic index. As an independent prognostic factor for overall survival, the GR proved to be significant (P = 0.024).

Conclusion  The GR of localized cutaneous melanomas may be a possible prognostic factor for survival. Additionally, rapid GR is associated with male patients more advanced in age at diagnosis, which suggests the need to assess new strategies for the early detection of these melanomas.