bluuebunny/crossref_metadata_2025_split huggingface dataset:
Childhood sexual abuse and risks for licit and illicit drug-related outcomes: a twin study
Authors: NELSON ELLIOT C. , HEATH ANDREW C. , LYNSKEY MICHAEL T. , BUCHOLZ KATHLEEN K. , MADDEN PAMELA A. F. , STATHAM DIXIE J. , MARTIN NICHOLAS G. 
Published: July 2006

Background. This study examined the relationships between self-reported childhood sexual abuse (CSA) and drug-related outcomes in an Australian twin panel.Method. A semi-structured psychiatric interview was conducted in 1996–2000 by telephone with young adult Australian twins (mean age 29·9 years). Data reported here are from 6050 twins who responded to both CSA and drug-related items.Results. A history of CSA was associated with significant risk for subsequently occurring regular smoking and use of each illicit drug class. Further CSA-associated risk was found among regular users, for nicotine and alcohol dependence, and among illicit drug users, for abuse/dependence of most drug classes. In same-sex discordant pairs, significant risk for regular smoking and illicit drug use was found in twins with a history of CSA compared to their non-abused co-twins. Similar analyses for abuse/dependence found significant risk for opioids, any illicit drug, and any non-cannabis illicit drug. CSA was associated with significantly earlier drug use. Despite the association of CSA with risk for early-onset cannabis use and regular smoking, risks for illicit drug outcomes associated with CSA and with either form of early-onset use combine in near-additive fashion.Conclusions. CSA is associated with risk for subsequently occurring regular smoking and illicit drug use and abuse/dependence. Risks for drug use are mildly attenuated with control for familial contributions; similar risks for abuse/dependence remain significant for opioids and for illicit drugs combined across classes. Although we found evidence of earlier onset drug use with CSA, risks associated with CSA and with early-onset use combine in a largely additive manner.
Unravelling Carbon Metabolism in Anaerobic Cellulolytic Bacteria
Authors: Desvaux Mickaël 
Published: July 2006

AbstractCarbon metabolism in anaerobic cellulolytic bacteria has been investigated essentially in Clostridium thermocellum, Clostridium cellulolyticum, Fibrobacter succinogenes, Ruminococcus flavefaciens, and Ruminococcus albus. While cellulose depolymerization into soluble sugars by various cellulases is undoubtedly the first step in bacterial metabolisation of cellulose, it is not the only one to consider. Among anaerobic cellulolytic bacteria, C. cellulolyticum has been investigated metabolically the most in the past few years. Summarizing metabolic flux analyses in continuous culture using either cellobiose (a soluble cellodextrin resulting from cellulose hydrolysis) or cellulose (an insoluble biopolymer), this review aims to stress the importance of the insoluble nature of a carbon source on bacterial metabolism. Furthermore, some general and specific traits of anaerobic cellulolytic bacteria trends, namely, the importance and benefits of (i) cellodextrins with degree of polymerization higher than 2, (ii) intracellular phosphorolytic cleavage, (iii) glycogen cycling on cell bioenergetics, and (iv) carbon overflows in regulation of carbon metabolism, as well as detrimental effects of (i) soluble sugars and (ii) acidic environment on bacterial growth. Future directions for improving bacterial cellulose degradation are discussed.
On‐Line Measurement of Gas Production Rates
Authors: Cooney Michael , Maynard Nathan , Cannizzaro Christopher , Harris David 
Published: July 2006

AbstractGas evolution rates represent an important variable to track in biological and certain electrochemical processes. Accurate gas flow rate sensors exist for gas streams possessing a pressure head, such as when pressurized air or oxygen is delivered to a fermentation process. However, these devices impose pressure heads that can inhibit gas production and, therefore, yield false measurements. Examples of effected processes would include electrochemical production of a gas at the electrode (e.g., electrolysis) or anaerobic fermentation (e.g., anaerobic production of methane). In this work, we present an on‐line gas measurement technique that measures on‐line gas production from an anaerobic microbial process that is continuously fed simulated food waste over a 6‐month period. Commentary is given on the sensorapos;s accuracy and ease of use within the context of long‐term operation, ability to measure both low and high gas production rates, as well as its potential for process control and system‐health monitoring.
Size of Rabbits consumed by Black Kites increased after a Rabbit epizootic
Authors: VILLAFUERTE R. , VIÑUELA J. 
Published: July 2006

AbstractRabbits are the staple prey for Black Kites in Matasgordas, south‐western Spain. Because of their poor predatory skills, it has been considered that most of the Rabbits consumed by Kites were young and affected by myxomatosis. After rabbit haemorrhagic disease (RHD) arrived in Spain, and since most of the Rabbits affected were adults, it was expected that the raptor would benefit with the incorporation of larger Rabbits in its diet. In concordance with that prediction, during the immediate three years before the arrival of RHD (1987–89), average size of Rabbits consumed by nestling Black Kites were similar and corresponded to the size of those Rabbits affected by myxomatosis. However, after RHD arrival in 1990, sizes of Rabbits consumed by Kites increased, corresponding to the age more frequently affected by RHD.
Developmental response to cold stress in cranial morphology of
Rattus
: implications for the interpretation of climatic adaptation in fossil hominins
Authors: Rae Todd C , Viðarsdóttir Una Strand , Jeffery Nathan , Steegmann A. Theodore 
Published: July 2006

Adaptation to climate occupies a central position in biological anthropology. The demonstrable relationship between temperature and morphology in extant primates (including humans) forms the basis of the interpretation of the Pleistocene hominin
Homo neanderthalensis
as a cold-adapted species. There are contradictory signals, however, in the pattern of primate craniofacial changes associated with climatic conditions.

To determine the direction and extent of craniofacial change associated with temperature, and to understand the proximate mechanisms underlying cold adaptations in vertebrates in general, dry crania from previous experiments on cold- and warm-reared rats were investigated using computed tomography scanning and three-dimensional digitization of cranial landmarks. Aspects of internal and external cranial morphology were compared using standard statistical and geometric morphometric techniques.
The results suggest that the developmental response to cold stress produces subtle but significant changes in facial shape, and a relative decrease in the volume of the maxillary sinuses (and nasal cavity), both of which are independent of the size of the skull or postcranium. These changes are consistent with comparative studies of temperate climate primates, but contradict previous interpretations of cranial morphology of Pleistocene Hominini.
Megakaryocyte development and platelet production
Authors: Deutsch Varda R. , Tomer Aaron 
Published: July 2006

SummaryMegakaryocytopoiesis involves the commitment of haematopoietic stem cells, and the proliferation, maturation and terminal differentiation of the megakaryocytic progenitors. Circulating levels of thrombopoietin (TPO), the primary growth‐factor for the megakaryocyte (MK) lineage, induce concentration–dependent proliferation and maturation of MK progenitors by binding to the c‐Mpl receptor and signalling induction. Decreased platelet turnover rates results in increased concentration of free TPO, enabling the compensatory response of marrow MKs to increased platelet production. C‐Mpl activity is orchestrated by a complex cascade of signalling molecules that induces the action of specific transcription factors to drive MK proliferation and maturation. Mature MKs form proplatelet projections that are fragmented into circulating particles. Newly developed thrombopoietic agents operating via c‐Mpl receptor may prove useful in supporting platelet production in thrombocytopenic state. Herein, we review the regulation of megakaryocytopoiesis and platelet production in normal and disease state, and the new approaches to thrombopoietic therapy.
Localisation of proteins of iron metabolism in the human placenta and liver
Authors: Bastin Judy , Drakesmith Hal , Rees Margaret , Sargent Ian , Townsend Alain 
Published: July 2006

SummaryTwo anatomical sites that are important in human iron metabolism are the liver and placenta. Liver macrophages recycle iron from erythrocytes, and the placenta transfers iron from the mother to the fetus. The cellular distribution of proteins involved in iron transport in these two sites was studied. Transferrin receptor‐1 (TfR1) and Ferroportin (FPN) expression was found on the placental syncytiotrophoblast (STB) and were polarised such that TfR1 was on the apical maternal‐facing membrane and FPN was on the basal fetal‐facing membrane, consistent with unidirectional iron transport from mother to fetus. Ferritin was strongly expressed in the stroma, suggesting that fetal tissue can store and accumulate iron. HFE was on some parts of the basal STB and, where present, HFE clearly colocalised with FPN but not TfR1. In the stroma, both HFE and FPN were present on CD68+ Hofbauer macrophage cells. In liver, the location of HFE is controversial. Using four mouse monoclonals and two polyclonal sera we showed that the pattern of HFE expression mirrored the distribution of CD68+ macrophage Kupffer cells. FPN was also most strongly expressed by CD68+ Kupffer cells. These findings contribute to understanding how iron is transported and stored in the human placenta and liver.
Fish community changes after minimum flow increase: testing quantitative predictions in the Rhône River at Pierre‐Bénite, France
Authors: LAMOUROUX NICOLAS , OLIVIER JEAN‐MICHEL , CAPRA HERVÉ , ZYLBERBLAT MARC , CHANDESRIS ANDRE , ROGER PASCAL 
Published: July 2006

Summary1. Many aspects of the flow regime influence the structure of stream communities, among which the minimum discharge left in rivers has received particular attention. However, instream habitat models predicting the ecological impacts of discharge management often lack biological validation and spatial generality, particularly for large rivers with many fish species.2. The minimum flow at Pierre‐Bénite, a reach of the Rhône river bypassed by artificial channels, was increased from 10 to 100 m3 s−1 in August 2000 (natural mean discharge 1030 m3 s−1), resulting in a fivefold increase in average velocity at minimum flow. Fish were electrofished in several habitat units on 12 surveys between 1995 and 2004.3. Principal components analysis revealed a significant change in the relative abundance of fish species. The relative abundance of species preferring fast‐flowing and/or deep microhabitats increased from two‐ to fourfold after minimum flow increase. A change in community structure confirmed independent quantitative predictions of an instream habitat model. This change was significantly linked to minimum flow increase, but not to any other environmental variables describing high flows or temperature at key periods of fish life cycle. The rapidity of the fish response compared with the lifespan of individual species can be explained by a differential response of specific size classes.4. The fish community at Pierre‐Bénite is in a transitional stage and only continued monitoring will indicate if the observed shift in community structure is perennial. We expect that our case study will be compared with other predictive tests of the impacts of flow restoration in large rivers, in the Rhône catchment and elsewhere.
Dispersal and climate change: a case study of the Arctic ternSterna paradisaea
Authors: MØLLER A. P. , FLENSTED‐JENSEN E. , MARDAL W. 
Published: July 2006

AbstractDispersal is an important evolutionary process that can affect admixture of populations and cause rapid responses to changing climatic conditions due to gene flow from populations at different altitudes or latitudes already experiencing these conditions. We investigated long‐term patterns of natal and breeding dispersal in a coastal seabird, the Arctic ternSterna paradisaea, that experiences specific climatic conditions in the northern temperate and Arctic climate zones during breeding and different climatic conditions in the Antarctic during winter. Long natal and breeding dispersal distances were costly as shown by their effects on delayed breeding. Dispersal distances varied significantly among years, with natal dispersal showing a strong temporal increase during the last 70 years. Annual differences in dispersal distance could be accounted for by climate conditions in the breeding grounds and the winter quarters. Natal dispersal was related to climate conditions in both the year of hatching and the year of breeding, whereas breeding dispersal was only related to climate conditions in the second year of the dispersal event. Only the north Atlantic oscillation (NAO) index for winter showed a consistent temporal trend, suggesting that the temporal trend in natal dispersal distance must be caused by changes in the NAO (or associated phenomena). These findings indicate that dispersal can change rapidly in response to changing climate conditions.
Loss of forb diversity in relation to nitrogen deposition in the UK: regional trends and potential controls
Authors: STEVENS CARLY J. , DISE NANCY B. , GOWING DAVID J. G. , MOUNTFORD J. OWEN 
Published: July 2006

AbstractIn this study we investigate the impact of nitrogen (N) deposition on the diversity of three different vegetation functional groups – forbs, grasses and mosses – using a field survey of acid grasslands across Great Britain. Our aim is to identify the vegetation types that are most vulnerable to enhanced N deposition, and to shed light on the mechanisms that may be driving N‐initiated species changes in the UK. Sixty‐eight randomly selected grasslands belonging to the UK National Vegetation Classification group U4 (Festuca ovina–Agrostis capillaris–Galium saxatile grassland) were studied along a gradient of atmospheric N deposition ranging from 6 to 36 kg N ha−1 yr−1. At each site, vegetation was surveyed and samples were taken from the topsoil and subsoil. Aboveground plant material was collected from three species: a forb, grass and moss. Both the species richness and cover of forbs declined strongly with increasing N deposition, from greater than eight species/20% cover per m2 quadrat at low levels of N to fewer than two species/5% cover at the highest N deposition levels. Grasses showed a weak but significant decline in species richness, and a trend toward increasing cover with increasing N input. Mosses showed no trends in either species richness or cover. Most of the decline in plant species richness could be accounted for by the level of ammonium deposition. Soil KCl‐extractable ammonium concentration showed a significant positive correlation with N input, but there was no relationship between N deposition and extractable nitrate. In the soil O/A horizon, there was no relationship between N deposition and %N, and only a very weak positive relationship between the level of N deposition and the C : N ratio. Finally, in the vegetation, there was no relationship between N deposition and either shoot tissue N concentration or N : P ratio for any of the three reference species. Combining our regional survey with the results of published N‐addition experiments provides compelling evidence that there has been a significant decline in the species richness and cover of forbs across Great Britain, and that the primary cause is competition due to an increase in the cover of grasses in response to enhanced deposition of reactive N, primarily NH4+.
Mycobacteria lacking the RD1 region do not induce necrosis in the lungs of mice lacking interferon‐γ
Authors: Junqueira‐Kipnis Ana Paula , Basaraba Randall J. , Gruppo Veronica , Palanisamy Gopinath , Turner Oliver C. , Hsu Tsungda , Jacobs William R. , Fulton Scott A. , Reba Scott M. , Boom W. Henry , Orme Ian M. 
Published: July 2006

SummaryThe genetic region of difference 1 (RD1) in Mycobacterium tuberculosis has recently been hypothesized to encode for proteins that are cytotoxic to the host cell in nature. We demonstrate here that while M. tuberculosis grew progressively in the lungs of gene disrupted mice (GKO) unable to produce interferon‐γ (IFN‐γ), similar mice infected instead with M. bovis bacillus Calmette–Guérin (BCG) reproducibly exhibited an obvious slowing of the disease after about 20 days. Closer examination of BCG‐infected GKO mice showed a florid granulomatous inflammation in the lungs, whereas similar mice infected with M. tuberculosis exhibited wholesale progressive necrosis. In the BCG‐infected GKO mice large numbers of activated effector T cells, some strongly positive for the cytokine tumour necrosis factor, as well as activated natural killer cells accumulated in the lungs. To further test the hypothesis that the differences observed were directly associated with the loss of the RD1 region, it was then shown that a mutant of M. tuberculosis lacking RD1 grew progressively in both normal and GKO mice but failed to induce any degree of necrosis in either animal despite reaching similar levels in the lungs. However, when mice were infected with this mutant, in which the RD1 region had been restored by complementation, wholesale necrosis of the lungs again occurred. These data support the hypothesis that proteins encoded in the RD1 region are a major cause of necrosis and contribute significantly to the pathogenesis of the disease.
Shaping ability of progressive versus constant taper instruments in simulated root canals
Authors: Yang G. B. , Zhou X. D. , Zhang H. , Wu H. K. 
Published: July 2006

AbstractAim  To compare the shaping ability of progressive versus constant taper shaft designed instruments in simulated root canals.Methodology  Simulated L‐ and S‐shaped resin canals were prepared by ProTaper (progressive taper) and high elasticity in rotation 642 (Hero 642) (constant taper) instruments (n = 10 canals in each case). The pre‐ and post‐instrumentation images were recorded and assessment of the canal shape was completed with image pro plus 5.0. The width of resin removed was measured at 9 measuring points. Incidence of canal aberrations, instrument fracture, preparation time and change of working length were recorded. In addition, the change of curvature and centring ability were also assessed. The data were analysed statistically using Student's t‐test or Fisher's exact‐test.Results  In both canal types, Hero 642 instruments prepared canals more rapidly (P < 0.01) and maintained working length significantly more accurately than ProTaper instruments (P < 0.05). In canals prepared with Hero 642 instruments, there was less change in curvature. Instrumentation with ProTaper results in transportation towards the outer aspect of the L‐shaped curved canals in the apical part and the inner aspect of the S‐shaped canals at the curve. Hero 642 instruments had a better centring ability in the apical part of the canal, but resulted in shapes with a poor taper.Conclusions  ProTaper and Hero 642 instruments prepared curved canals rapidly, maintained working length well and were relatively safe without creating perforations and danger zones. In both canal types, Hero 642 instruments maintained the original canal curvature better, and had a better centring ability in curved canals because of its constant taper design. The taper prepared by Hero 642 instruments in the coronal part of the canal was generally poor.
Modeling Low Temperature Blanched Carrot Firmness Based on Heat Induced Processes and Enzyme Activity
Authors: VERLINDEN BERT E. , DE BAERDEMAEKER JOSSE 
Published: July 2006

ABSTRACTA kinetic texture model was developed describing the low temperature blanching firming effect. The rupture stress of carrots during blanching at 55°, 65° and 75°C and subsequent cooking at 95° and 100°C was measured. Firming effects were highest at 55° and 65°C although shorter blanching times were needed at 65°C. Model parameters were estimated by non‐linear regression analysis on these measurements. The model summarized the biochemical mechanisms occurring in the cell wall during processing. The model was suitable for process design purposes as well as for gaining a better understanding of the firming process.
Explicit Finite Difference Methods for Heat Transfer Simulation and Thermal Process Design
Authors: WELT B.A. , TEIXEIRA A.A. , CHAU K.V. , BALABAN M.O. , HINTENLANG D.E. 
Published: July 2006

ABSTRACTA considerable difference between two explicit finite difference heat transfer simulation approaches was described. Time step restrictions, which are often the basis for criticism of explicit methods, were shown to be less severe when the surface was not considered to have thermal mass. Thermal process design combines heat transfer and reaction kinetics considerations. Accuracy of lethality estimates depends on time step size. Guidelines were developed for applying discrete time‐temperature data to thermal process calculations. For time steps small enough to permit a linear temperature change approximation, it was shown that for increasing (decreasing) temperatures, a value within 50 to 60% (40 to 50%) of total temperature change should be used.
Properties of Anthocyanins from Grape Cell Culture
Authors: CORMIER F. , COUTURE R. , DO C.B. , PHAM T.Q. , TONG V.H. 
Published: July 2006

ABSTRACTColor and thermal‐ and pH‐stability of anthocyanins from a grape cell suspension culture were compared with those of commercial food colorants using Hunter and spectrophotometric analysis. At pH 3, grape cell anthocyanins showed color vividness (Chroma) similar to red cabbage and higher than that of other samples and a hue (Theta) similar to purple corn and redder than other samples. Brown oxidized phenolics were absent from the cell culture and red cabbage preparations, but were found in other samples. Color loss during incubation at 30 and 95°C, pH 3 and during an increase in pH from 3 to 5 was more severe for cell culture than red cabbage anthocyanins probably indicating they were intrinsically more sensitive.
Browning Susceptibility and Changes in Composition During Storage of Carambola Slices
Authors: WELLER A. , SIMS C.A. , MATTHEWS R.F. , BATES R.P. , BRECHT J.K. 
Published: July 2006

ABSTRACTBrowning and changes in the composition of sliced and whole carambola (Averrhoa carambola L.) fruit during storage were investigated. Susceptibility to browning after slicing, packaging and storage for 4 wk at 4.4°C varied considerably between four cultivars and five selections. There was no difference in browning susceptibility between fruit harvested at mature green or breaker stages of maturity. Freshly sliced carambola browned only slightly when exposed to air, but packaged slices that had been stored for 2 or more wk at 4.4°C browned rapidly (within 6 hr) when exposed to air. Whole fruit stored at 4.4°C for up to 6 wk, then sliced, showed much less susceptibility to browning. Ascorbic acid decreased and polyphenoloxidase activity increased in carambola slices during storage, but less in whole fruit. Treating slices with 1.0 or 2.5% citric acid + 0.25% ascorbic acid (in water) prior to packaging was very effective in limiting browning.