bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modelling the effect of temperature on carbon mineralization rates across a network of European forest sites (FORCAST)
Authors: REY ANA , JARVIS PAUL 
Published: August 2006

AbstractTemperature is a major environmental variable influencing microbial respiration in soils. Thus, understanding how heterotrophic processes in soils may respond to potential increases in temperature is crucial for the prediction of the response of forest carbon budgets to climate change. We investigated carbon mineralization rates from eight European forest soils in relation to soil temperature. Mineral soil samples were collected from eight mature forest sites in the European network CARBOEUROFLUX and were incubated in the laboratory for ca. 270 days at four temperatures: 4, 10, 20 and 30°C. In all soils, carbon mineralization rates decreased over time when incubated at high temperatures of 20 and 30°C. In this study, we explore the different models available to analyse long‐term incubation data. Carbon mineralization rates were best predicted by a first‐order, two‐compartment model that predicted carbon mineralization as a function of time and temperature using all of the incubation data. We found very small fractions (1–9%) of labile carbon in the upper mineral soils. Despite large differences among sites, we found higher carbon mineralization rates and larger amounts of labile carbon in the broadleaf than in the conifer forest soils. No significant differences in temperature sensitivity among the sites (averageQ10of 2.88 using the two‐compartment model) were observed, as estimated with all methods used. Although not statistically significant, the sensitivities of the rate constant of the labile fractions tended to be higher than those for the rate constant of the recalcitrant fractions. Thus, the results of this modelling exercise suggest that despite large variation among sites, a single temperature sensitivity parameter can be used for a range of soils over the range of temperatures we used (4–30°C).
A simple statistical model for predicting herbage production from permanent grassland
Authors: Trnka M. , Eitzinger J. , Gruszczynski G. , Buchgraber K. , Resch R. , Schaumberger A. 
Published: August 2006

AbstractThe considerable year‐to‐year and seasonal variation in grassland production is of major importance to dairy farmers in Europe, as production systems must allow for the risk of unfavourable weather conditions. A large portion of the variability is caused by weather and its interaction with soil conditions and grassland management. The present study takes advantage of the interactions between weather, soil conditions and grassland management to derive a reliable grassland statistical model (GRAM) for grasslands under various management regimes using polynomial regressions (GRAM‐R) and neural networks (GRAM‐N). The model performance was tested with a focus on predicting its capability during unusually dry or wet years using long‐term experimental data from Austrian sites. The GRAM model was then coupled with the Met&Roll stochastic weather generator to provide estimates of harvestable herbage dry matter (DM) production early in the season. It was found that, with the GRAM‐N or GRAM‐R methodology, up to 0·78 of the variability in harvested herbage DM production could be explained with a systematic bias of 1·1–2·3%. The models showed stable performance over subsets of dry and wet years. Generalized GRAM models were also successfully used to estimate daily herbage growth during the season, explaining between 0·63 and 0·91 of variability in individual cases. It was possible to issue a probabilistic forecast of the harvestable herbage DM production early in the season with reasonable accuracy. The overall results showed that the GRAM model could be used instead of (or in parallel with) more sophisticated grassland models in areas or sites where complete data sets are not yet available. As the model was tested under various climatic and soil conditions, it is suggested that the proposed approach could be used for comparable temperate grassland sites throughout Europe.
The effect of the density and physical properties of grass stems on the foraging behaviour and instantaneous intake rate by cattle grazing an artificial reproductive tropical sward
Authors: Benvenutti M. A. , Gordon I. J. , Poppi D. P. 
Published: August 2006

AbstractIn reproductive swards, stems appear to act as vertical or horizontal barriers to bite formation, influencing instantaneous intake rate (IIR). The hypothesis was tested that the stems’ barrier effect is determined by the physical properties and density of stems. Artificial microswards, consisting of 20‐cm leaves and 15‐cm stems of Panicum maximum, were offered to three steers (362 kg) in a factorial combination of three stem densities (0, 100 and 400 stems m−2) and two levels of stem tensile resistance [low (LTRS) and high tensile‐resisting stems (HTRS)]. LTRS were not a barrier to defoliation and did not affect bite depth and bite mass. HTRS acted as both a horizontal barrier and a vertical barrier depressing bite depth (13·4, 13·6 and 5·1 cm for 0, 100 and 400 stems m−2, respectively), bite area (89·3, 50·8 and 47·6 cm2 for 0, 100 and 400 stems m−2, respectively), bite mass (0·51, 0·29 and 0·11 g for 0, 100 and 400 stems m−2, respectively) and IIR (23·8, 10·5 and 3·6 g sec−2 for 0, 100 and 400 stems m−2, respectively). The results confirmed the importance of the density and physical properties of stems as determinants of the stems’ barrier effect on bite dimensions and IIR.
Volatile fatty acid proportions and microbial protein synthesis in the rumen of cattle receiving grass silage ensiled with different rates of formic acid
Authors: Jaakkola S. , Kaunisto V. , Huhtanen P. 
Published: August 2006

AbstractTimothy–meadow fescue herbage was ensiled with formic acid (FA) (expressed as 100% solution) at the rates of 0, 2, 4 or 6 L t−1. The silages were fed along with concentrates to bulls fitted with cannulae in the rumen and duodenum. The ration comprised grass silage (700 g kg−1), barley (240 g kg−1) and rapeseed meal (60 g kg−1). The application rate of FA had no effect on the site or extent of the digestion of dietary organic matter (OM) and neutral‐detergent fibre. The flow of total N at the duodenum increased linearly (P < 0·05) with application rate of FA, reflecting mainly an increased (P < 0·01) flow of microbial N. The apparent efficiency of net microbial protein synthesis in the rumen increased (P < 0·05), the proportion of propionate in the volatile fatty acids (VFA) in the rumen was not affected (P > 0·05) but that of butyrate increased (linear and quadratic effects, P < 0·01) with increasing rate of FA. It is concluded that an increase in the rate of FA at ensiling leads to a higher utilization of energy and/or protein‐yielding substrates for rumen microbes and to a modified rumen VFA pattern with an increased proportion of butyrate.
Dairy cow performance and labour inputs associated with two silage feeding systems
Authors: Ferris C. P. , Frost J. P. , Binnie R. C. , Patterson D. C. 
Published: August 2006

AbstractTwo experiments were conducted to examine the effect of two winter feeding systems on the performance of dairy cows in early lactation. Experiments 1 (144 d duration) and 2 (146 d duration) involved sixty‐four (primiparous) and eighty‐six (primiparous and multiparous) Holstein Friesian dairy cows respectively. Rations offered comprised grass silage, maize silage [0·26–0·29 of forage dry matter (DM)] and concentrates (10–12 kg d−1). With the complete diet (treatment CD), the forage and concentrate components were mixed using a complete diet mixer wagon, and offered daily in the form of a ‘complete diet’. With the easy feed (treatment EF), the dairy cows were offered the forage component of the ration twice weekly in whole blocks, in quantities sufficient for the following 3‐ or 4‐d period, while the concentrate component of the diet was offered via electronic out‐of‐parlour feeding stations. Total DM intakes were similar, namely 17·6 and 17·0 kg d−1 (Experiment 1) and 18·7 and 18·5 kg d−1 (Experiment 2), for treatments CD and EF respectively. Feeding system had no significant effect on milk yield, milk fat or milk protein content, or on end of study indices of body tissue reserves in either experiment (P > 0·05). Similarly, feeding system had no significant effect on the digestibility of the ration measured in Experiment 2 (P > 0·05). Feeding times associated with each component of the two feeding systems were measured, and these were then used to calculate total feeding time for a 97‐cow dairy herd. Calculated feeding times for this herd were 209·3 and 156·0 min week−1 for treatments CD and EF respectively.
Cytoplasmic localization of p63 is associated with poor patient survival in lung adenocarcinoma
Authors: Narahashi T , Niki T , Wang T , Goto A , Matsubara D , Funata N , Fukayama M 
Published: August 2006

Aims : To determine the significance of p63 protein expression in the development and progression of lung adenocarcinoma.Mehods and results : The expression of p63 was immunohistochemically investigated in 92 cases of lung adenocarcinoma with a maximum diameter of 30 mm or less. p63 expression was observed not only in the nuclei (46/92 cases, 50%), but also in the cytoplasm of neoplastic cells (47/92, 51%). Nuclear localization of p63 was correlated with nuclear accumulation of p53 (P = 0.0120), whereas the presence of nuclear p63 had no apparent effect on patient survival. Cytoplasmic localization of p63 was found to be correlated with shorter survival periods by univariate and multivariate analyses (P = 0.0486 and P = 0.0488, respectively) and the relation was independent of clinicopathological factors. Cytoplasmic localization of p63 was further confirmed by immunoblots of the cytoplasmic fraction of HLC‐1, a lung adenocarcinoma cell line which predominately expressed ΔNp63α transcript relative to TAp63 transcript by quantitative reverse transcriptase‐polymerase chain reaction.Conclusions : Cytoplasmic expression of p63 is an adverse prognostic factor in patients with adenocarcinoma of the lung.
Onset of promiscuous gene expression in murine fetal thymus organ culture
Authors: Sousa Cardoso Renato , Magalhães Danielle A. R. , Baião Ana Maria T. , Junta Cristina Moraes , Macedo Claudia , Marques Márcia M. C. , Sakamoto‐Hojo Elza Tiemi , Donadi Eduardo A. , Passos Geraldo A. S. 
Published: August 2006

SummaryT‐cell differentiation and induction of tolerance to self‐antigens occurs mainly in the thymus. Thymic stromal cells, specifically medullary thymic epithelial cells, express a diverse set of genes encoding parenchymal organ‐specific proteins. This phenomenon has been termed promiscuous gene expression (PGE) and has been implicated in preventing organ‐specific autoimmunity by inducing T‐cell tolerance to self antigens. Early thymopoiesis and the critical factors involved in T‐cell differentiation can be reproduced in vitro by murine fetal thymus organ culture (FTOC), which mimics the natural thymic microenvironment. To evaluate the occurrence of PGE in FTOC, gene expression profiling during in vitro thymic development in BALB/c mice was performed using a set of nylon cDNA microarrays containing 9216 sequences. The statistical analysis of the microarray data (sam program) revealed the temporal repression and induction of 57 parenchymal and seven lymphoid organ‐specific genes. Most of the genes analysed are repressed during early thymic development (15–17 days post‐coitum). The expression of the autoimmune regulator (AIRE) gene at 16 days post‐coitum marks the onset of PGE. This precedes the induction of parenchymal organ genes during the late developmental phase at 20 days post‐coitum. The mechanism of T‐cell tolerance induction begins during fetal development and continues into adulthood. Our findings are significant because they show a fine demarcation of PGE onset, which plays a central role in induction of T‐cell tolerance.
Herpes virus entry mediator synergizes with Toll‐like receptor mediated neutrophil inflammatory responses
Authors: Haselmayer Philipp , Tenzer Stefan , Kwon Byoung S. , Jung Gundram , Schild Hansjörg , Radsak Markus P. 
Published: August 2006

SummaryIn microbial infections polymorphnuclear neutrophils (PMN) constitute a major part of the innate host defence, based upon their ability to rapidly accumulate in inflamed tissues and clear the site of infection from microbial pathogens by their potent effector mechanisms. The recently described transmembrane receptor herpes virus entry mediator (HVEM) is a member of the tumour necrosis factor receptor super family and is expressed on many haematopoietic cells, including T cells, B cells, natural killer cells, monocytes and PMN. Interaction of HVEM with the natural ligand LIGHT on T cells has a costimulatory effect, and increases the bactericidal activity of PMN. To further characterize the function of HVEM on PMN, we evaluated the effect of receptor ligation on human PMN effector functions using an agonistic monoclonal antibody. Here we demonstrate that activation of HVEM causes activation of neutrophil effector functions, including respiratory burst, degranulation and release of interleukin‐8 in synergy with ligands for Toll‐like receptors or GM‐CSF. In addition, stimulation via HVEM enhanced neutrophil phagocytic activity of complement opsonized, but not of non‐opsonized, particles. In conclusion, these results indicate a new, as yet unknown, participation of HVEM in the innate immune response and points to a new link between innate and adaptive immunity.
The effect of advice to walk 2000 extra steps daily on food intake
Authors: Koulouri A.‐A. , Tigbe W. W. , Lean M. E. J. 
Published: August 2006

AbstractBackground  It is currently unclear how physical activity and diet interact within the ranges of activity seen in the general population. This study aimed to establish whether a small, acute, increase in physical activity would lead to compensatory change in energy intake and nutrient balance, and to provide power analysis data for future research in this field.Method  Twelve participants were studied over 7 days of habitual activity and 2 weeks after instruction to increase physical activity by 2000 steps per day. Physical activity was assessed using a diary, the ‘activPAL’ activity monitor and a pedometer. Dietary analyses from prospective food diaries were compared between the first and third weeks.Results  Participants increased step‐counts (+2600 steps per day, P = 0.008) and estimated energy expenditure (+300–1000 kJ day−1, P = 0.002) but did not significantly change their energy intake, dietary composition or number of meals per day. From reverse power analysis 38 participants would be needed to exclude a change in energy intake of 400 kJ day−1 with 90% power at P < 0.05; 400 kJ day−1 would compensate for a 2000 steps per day increase in physical activity.Conclusion  These results did not demonstrate any compensatory increase in food consumption when physical activity was increased by walking an average of 2600 additional steps per day. Power analysis indicates that a larger study (n = 38) will be necessary to exclude such an effect with confidence.
Processes underlying young women's decisions to eat fruits and vegetables
Authors: Chung S.‐J. , Hoerr S. , Levine R. , Coleman G. 
Published: August 2006

AbstractObjective  To relate the use of identified processes that college women use to eat enough fruits and enough vegetables to their stages of readiness to change and their fruit and vegetable (F/V) intakes.Method  A cross‐sectional assessment of college women 18–24 years of age (n = 236) was conducted to assess stage of readiness to eat F/V. Use of seven processes, earlier confirmed in a separate sample of college students the same age (health concerns, self‐reevaluation, social liberation, health commitment/action, interpersonal control, external reinforcement and helping relationships) was compared with stage of change for F/V and 3 days of dietary intakes.Results  In these young college women, use of self‐reevaluation, a cognitive process for change, peaked in the preparation stage for both F/V. Use of health commitment/action, a post‐action process including counter‐conditioning, peaked in those in action/maintenance for F/V. Weight concerns related to the counter‐conditioning processes women used to eat more fruit.Conclusion  Health practitioners should focus on weight management, appearance and health benefits of eating fruits and vegetables for this demographic group.
Prepregnancy body mass index and dietary intake in the first trimester of pregnancy
Authors: Derbyshire E. , Davies J. , Costarelli V. , Dettmar P. 
Published: August 2006

AbstractObjectives  Adequate maternal nutrition is of paramount importance in pregnancy, particularly in the first trimester when fetal development is crucial. It has been reported that heavier women are most likely to fear weight gain associated with pregnancy. Few studies have, however, investigated associations between prepregnancy body mass index (BMI) and nutrient intakes in the first trimester of gestation using detailed, prospective methodologies. The aim of this study was to investigate possible associations between prepregnancy BMI and nutrient intakes in the first trimester of gestation.Design  Seventy‐two Caucasian, primiparous nonsmokers of mean age 33.1 years (SD 4.6) were recruited from three London teaching hospitals and they completed a background information questionnaire and a 4‐ to 7‐day weighed inventory food diary during the first trimester of pregnancy. Prepregnancy anthropometric data were extracted from General Practitioner records.Results  Prepregnancy BMI was inversely associated with dietary energy (P = 0.04), Southgate and Englyst fibre (P < 0.01), and iron and folate (P < 0.01). After excluding under‐reporters [individual energy intake:basal metabolic rate (estimated) ratio < 1.2], prepregnancy BMI was inversely associated with folate intake (P =0.04). Dietary intakes of Englyst fibre (P = 0.03) were statistically significantly lower than average dietary recommendations in this group.Conclusions  This study identified that women with a high prepregnancy BMI are more likely to under‐report nutrient intakes. The finding that folate intake was significantly lower in heavier women accurately reporting dietary intake is of particular concern.
Characterization of the three‐dimensional structure of a metallic foam during compressive deformation
Authors: MCDONALD S. A. , MUMMERY P. M. , JOHNSON G. , WITHERS P. J. 
Published: August 2006

SummaryX‐ray microtomography has been employed to collect three‐dimensional images of aluminium closed‐cell foam, enabling the internal structure to be characterized in three dimensions. An experimental technique and image analysis approach has been developed, and is described, in terms of the labelling of cells and the extraction of quantitative data such as the cell volume and cell compression. An in situ compressive deformation experiment has been performed on a single sample in order to illustrate the approach. The effect of the three‐dimensional cellular structure on the mechanisms of deformation suggests not only the position of large cell volumes to be very important in the local concentration of stress, but also the distribution of cell volumes of immediate neighbours.
Linear least‐squares fit evaluation of series of analytical spectra from planar defects: extension and possible implementations in scanning transmission electron microscopy
Authors: WALTHER T. 
Published: August 2006

SummaryIn a previous paper, a new technique was introduced to determine the chemistry of crystallographically well‐defined planar defects (such as straight interfaces, grain boundaries, twins, inversion or antiphase domain boundaries) in the presence of homogeneous solute segregation or selective doping. The technique is based on a linear least‐squares fit using series of analytical (electron energy‐loss or energy‐dispersive X‐ray) spectra acquired in a transmission electron microscope that is operated in nano‐probe mode with the planar defect centred edge‐on. First, additional notes on the use of proper k‐factors and determination of Gibbsian excess segregation are given in this note. Using simulated data sets, it is shown that the linear least‐squares fit improves both the accuracy and the robustness to noise beyond that obtainable by independently repeated measurements. It is then shown how the method originally developed for a stationary nano‐probe mode in transmission electron microscopy can be extended to a focused electron beam that scans a square region in scanning transmission electron microscopy. The necessary modifications to scan geometry and corresponding numerical evaluation are described, and three different practical implementations are proposed.
The exosome: a macromolecular cage for controlled RNA degradation
Authors: Büttner Katharina , Wenig Katja , Hopfner Karl‐Peter 
Published: August 2006

SummaryThe exosome, a large multisubunit complex with exoribonucleic activity, emerges as the central 3′ RNA degradation and processing factor in eukaryotes and archaea. But how are the many RNA substrates of the exosome degraded in a processive, yet controlled manner? Recent functional and structural progress shows that the exosome is a macromolecular cage, where the nuclease active sites are situated in a central processing chamber. A narrow entry pore controls access to the active sites in the processing chamber and prevents uncontrolled RNA decay. The emerging mechanism of exosome function suggests a strikingly parallel architectural concept to protein degradation by proteasomes.
A systematic genetic analysis in Neisseria meningitidis defines the Pil proteins required for assembly, functionality, stabilization and export of type IV pili
Authors: Carbonnelle Etienne , Helaine Sophie , Nassif Xavier , Pelicic Vladimir 
Published: August 2006

SummaryAlthough type IV pili (Tfp) are among the commonest virulence factors in bacteria, their biogenesis by complex machineries of 12–15 proteins, and thereby their function remains poorly understood. Interestingly, some of these proteins were reported to merely antagonize the retraction of the fibres powered by PilT, because piliation could be restored in their absence by a mutation in the pilT gene. The recent identification of the 15 Pil proteins dedicated to Tfp biogenesis in Neisseria meningitidis offered us the unprecedented possibility to define their exact contribution in this process. We therefore systematically introduced a pilT mutation into the corresponding non‐piliated mutants and characterized them for the rescue of Tfp and Tfp‐mediated virulence phenotypes. We found that in addition to the pilin, the main constituent of Tfp, only six Pil proteins were required for the actual assembly of the fibres, because apparently normal fibres were restored in the remaining mutants. Restored fibres were surface‐exposed, except in the pilQ/T mutant in which they were trapped in the periplasm, suggesting that the PilQ secretin was the sole Pil component necessary for their emergence on the surface. Importantly, although in most mutants the restored Tfp were not functional, the pilG/T and pilH/T mutants could form bacterial aggregates and adhere to human cells efficiently, suggesting that Tfp stabilization and functional maturation are two discrete steps. These findings have numerous implications for understanding Tfp biogenesis/function and provide a useful groundwork for the characterization of the precise function of each Pil protein in this process.