bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantifying sample bias in clast fabric measurements
Authors: CHANDLER DAVID M. , HUBBARD BRYN 
Published: February 2008

AbstractSampling elongate clasts that protrude from a planar face for clast macro‐fabric analysis introduces a bias into reconstructed fabrics because clasts aligned perpendicular to the sampling face are over‐represented relative to those aligned parallel to the face. This study develops a probability‐based mathematical analysis to quantify sample bias for a variety of clast shapes and population fabrics, including isotropic, clustered and girdled fabric styles. Bias is expressed in terms of sample eigenvalues and eigenvectors relative to those of the parent population. Results indicate that sampling always has the effect of artificially drawing fabrics towards perpendicularity to the sampling face relative to the populations from which they are drawn. This rotation generally has the effect of artificially strengthening population fabrics, by up to 30% in the case of very weakly clustered or girdled populations. However, fabric strengthening is by no means universal and sampling alters different parent populations in different, sometimes complex, ways: the analysis in this paper identifies situations where sampling can strengthen or weaken parent fabrics, where it can rotate parent fabrics (by up to 90° in the case of a very weak population fabric), and where it can even change the style of a population fabric. For example, near‐isotropic population fabrics can appear clustered; weakly clustered and weakly girdled population fabrics can appear isotropic; weakly clustered population fabrics can appear weakly girdled; and girdled population fabrics can appear clustered. Overall, this analysis indicates that weakly orientated population fabrics are most susceptible to bias. Thus, a weakly clustered population fabric aligned parallel to a sample face is particularly susceptible to major sample bias in both fabric strength (artificially overestimated) and orientation (artificially rotated perpendicular to the face). Bias can be reduced either by sampling all the clasts from a cube‐shaped block of sediment excavated from the face, or by sampling equal numbers of clasts from the three orthogonal faces of the same sedimentary unit.
Characterization of a sub‐family of Arabidopsis genes with the SPX domain reveals their diverse functions in plant tolerance to phosphorus starvation
Authors: Duan Ke , Yi Keke , Dang Lei , Huang Hongjie , Wu Wei , Wu Ping 
Published: February 2008

SummaryFour genes of Arabidopsis (At5g20150, At2g26660, At2g45130 and At5g15330) encoding no conservative region other than an SPX domain (SYG1, Pho81 and XPR1) were named AtSPX1–AtSPX4. The various subcellular localizations of their GFP fusion proteins implied function variations for the four genes. Phosphate starvation strongly induced expression of AtSPX1 and AtSPX3 with distinct dynamic patterns, while AtSPX2 was weakly induced and AtSPX4 was suppressed. Expression of the four AtSPX genes was reduced to different extents in the Arabidopsis phr1 and siz1 mutants under phosphate starvation, indicating that they are part of the phosphate‐signaling network that involves SIZ1/PHR1. Over‐expression of AtSPX1 increased the transcript levels of ACP5, RNS1 and PAP2 under both phosphate‐sufficient and phosphate‐deficient conditions, suggesting a potential transcriptional regulation role of AtSPX1 in response to phosphate starvation. Partial repression of AtSPX3 by RNA interference led to aggravated phosphate‐deficiency symptoms, altered P allocation and enhanced expression of a subset od phosphate‐responsive genes including AtSPX1. Our results indicate that both AtSPX1 and AtSPX3 play positive roles in plant adaptation to phosphate starvation, and AtSPX3 may have a negative feedback regulatory role in AtSPX1 response to phosphate starvation.
Palladium exposure of barley: uptake and effects
Authors: Battke F. , Leopold K. , Maier M. , Schmidhalter U. , Schuster M. 
Published: February 2008

AbstractMotor vehicles are now equipped with exhaust gas catalytic converters containing rare metals, such as palladium (Pd), platinum and rhodium, as catalytic active materials, leading to significantly increased emission of these metals. Compared with platinum and rhodium, low concentrations of Pd have been shown to have more serious effects on cells and organisms. In the present study, uptake of Pd by barley and behaviour of Pd nanoparticles in nutrient solutions used to grow plants were observed in order to develop a model of Pd exposure of plant systems. Pd determination was performed using a selective separation and pre‐concentration procedure, which was further developed for this study, and coupled to graphite furnace atomic absorption spectrometry. The results show that uptake of Pd depends on Pd particle diameter. Compared to other toxic metals, like mercury, Pd causes stress effects in leaves at lower concentrations in nutrient solutions. Furthermore, Pd particles are dissolved at different rates, depending on size, in the nutrient solution during plant growth.
The proton pump interactor (Ppi) gene family of Arabidopsis thaliana: expression pattern of Ppi1 and characterisation of knockout mutants for Ppi1 and 2
Authors: Anzi C. , Pelucchi P. , Vazzola V. , Murgia I. , Gomarasca S. , Beretta Piccoli M. , Morandini P. 
Published: February 2008

AbstractPlant plasma membrane H+‐ATPases (PM H+‐ATPase) are essential for establishing a proton electrochemical gradient across the cell plasma membrane. Their regulation is poorly understood, except for the role of 14‐3‐3 proteins, which relieve autoinhibition from the C‐terminal domain. A novel protein interacting with this domain was recently identified in Arabidopsis and named PPI1 (Proton Pump Interactor 1). PPI1 stimulates PM H+‐ATPase activity in vitro. Here, we analyse the expression pattern of Ppi1 using β‐glucuronidase as a reporter. Expression is strong in root and shoot vascular systems, particularly in meristematic and sink tissues, as well as in pollen, stigmas and siliques, but not in developing embryos. Removal of the first intron decreased GUS expression 45‐fold. We also analysed the transcription of Ppi2, another gene in the family, and demonstrated that Ppi2 is expressed in seedlings, cultured cells and flowers. We reassessed Ppi2 gene structure based on RT‐PCR amplifications, cDNA data and similarity to other Ppi genes. Insertional mutants for both Ppi1 and Ppi2 were isolated. Two different mutants of Ppi1 showed aberrant mRNAs and lacked any detectable protein and are therefore true knockouts. Interestingly, one mutation inhibited the splicing of one intron at a considerable distance (>700 bp) from the T‐DNA insertion site, but not the splicing of a proximal intron (29 bp) or of any other intron. At the plant level, neither of the single mutants nor the double ppi1ppi2 mutant showed an altered phenotype in standard growth conditions under acid load or salt stress.
Holocrine secretion and cytoplasmic content of Helleborus foetidus L. (Ranunculaceae) nectar
Authors: Vesprini J. L. , Nepi M. , Ciampolini F. , Pacini E. 
Published: February 2008

AbstractWe used electron microscopy to investigate the fine structure of nectary secretions of Helleborus foetidus. During the secretion period, epidermal cells of nectaries discharge the whole contents of the cytoplasm into the nectary cavity. The external wall of the cell breaks, releasing the cytoplasm as a dense aggregate that later disperses in the nectary cavity. Cell components, such as chromatin, plastids, mitochondria, lipid droplets and membranes, were found in the nectar of H. foetidus, evincing the complex nature of the secreted material. These results confirm that nectar secretion in H. foetidus is of the holocrine type.
Effect of vitamin E supplementation of sheep and goats fed diets supplemented with polyunsaturated fatty acids and low in Se
Authors: Liesegang A. , Staub T. , Wichert B. , Wanner M. , Kreuzer M. 
Published: February 2008

SummaryVitamin E (VitE) and selenium (Se) are an essential part of the antioxidative functions of metabolism. There are situations of low supply of both micronutrients. As VitE is involved in ruminal biohydrogenation of polyunsaturated fatty acids (PUFA) and their protection against oxidation in metabolism, diets supplemented with PUFA may challenge VitE to an extent making recommended supplies insufficient. Twelve goats and sheep each were fed a diet supplemented with PUFA and characterised by low Se and limited VitE contents during the last 2 months of gestation and the first 2 months of lactation. The basal diet consisted of hay and concentrate. Six goats and sheep received extra VitE, while the control groups received no extra VitE. Blood and milk samples were taken. In addition, liver, heart muscle and spleen samples were obtained from the offspring after slaughtering at an age of 8 weeks. No significant changes were observed in serum Se and VitE. A significant increase in serum VitE concentrations between 2 and 4 weeks postpartum (pp) was evident in the supplemented kids. In 4, 6 and 8 weeks pp, the serum concentrations of VitE in the supplemented kids were significantly higher compared to the unsupplemented group. In the kids, VitE was higher in liver of the supplemented groups. There were no significant differences in response to extra VitE between sheep and goat. The kids responded to serum VitE different from that of lambs, as a significant difference was observed between supplemented and unsupplemented animals in the goat kids, but not the lambs. In conclusion, goats and sheep have to be viewed differently and may not be considered alike relating to VitE/Se metabolism and requirements, especially in young animals.
Spelt, an ancient cereal and first pressure linseed oil as ingredients of compound feedstuffs for modern horse feeding
Authors: Fayt J. , Dotreppe O. , Hornick J. L. , Istasse L. 
Published: February 2008

SummarySpelt is a covered cereal with large glumellas. In experiment 1, it has been compared in terms of chemical composition with barley, oat and maize. Spelt is characterized by rather low protein and ether extract (EE) contents. The neutral detergent fibre (NDF) content of spelt was slightly higher than that of oat but the acid detergent fibre (ADF) content was lower. Two compound feedstuffs were fed along with hay to six horses used in a cross‐over design. Both diets were well appreciated by the horses and there were no significant differences in the apparent digestibility coefficients, except for EE which was significantly higher, when oat was included in the compound feedstuff. In experiment 2, first pressure linseed oil was incorporated at a rate of 8% in a control compound feedstuff, where the barley was partly substituted by the oil. The fat content was 9.6% dry matter (DM) in the linseed oil compound feedstuff and 5.4% in the hay‐concentrate ration. The inclusion of linseed oil increased the digestibility of DM, EE and NDF of the diet. There were no effects on the post‐prandial concentrations of glucose, triglycerides and non‐esterified fatty acids (NEFA) but the insulin concentration was significantly reduced with the linseed oil inclusion. There were significant increases in the plasma concentrations of the total fatty acids, polyunsaturated fatty acids (PUFA), saturated fatty acids (SFA), C18:3 n‐3 and C18:2 n‐6 and significant reductions in the contents of monounsaturated fatty acids (MUFA), C18:1 n‐7 + n‐9 and C20:4 n‐6. It is concluded that the inclusions of spelt and first pressure linseed oil in compound feed stuff for horse are of interest for modern horse feeding.
Effect of dietary α‐tocopherol + ascorbic acid, selenium, and iron on oxidative stress in sub‐yearling Chinook salmon (Oncorhynchus tshawytscha Walbaum)
Authors: Welker T. L. , Congleton J. L. 
Published: February 2008

SummaryA three‐variable central composite design coupled with surface‐response analysis was used to examine the effects of dietary α‐tocopherol + ascorbic acid (TOCAA), selenium (Se), and iron (Fe) on indices of oxidative stress in juvenile spring Chinook salmon. Each dietary factor was tested at five levels for a total of fifteen dietary combinations (diets). Oxidative damage in liver and kidney (lipid peroxidation, protein carbonyls) and erythrocytes (erythrocyte resistance to peroxidative lysis, ERPL) was determined after feeding experimental diets for 16 (early December) and 28 (early March) weeks. Only TOCAA influenced oxidative stress in this study, with most measures of oxidative damage decreasing (liver lipid peroxidation in December and March; ERPL in December; liver protein carbonyl in March) with increasing levels of TOCAA. We also observed a TOCAA‐stimulated increase in susceptibility of erythrocytes to peroxidative lysis in March at the highest levels of TOCAA. The data suggest that under most circumstances a progressive decrease in oxidative stress occurs as dietary TOCAA increases, but higher TOCAA concentrations can stimulate oxidative damage in some situations. Higher levels of TOCAA in the diet were required in March than in December to achieve comparable levels of protection against oxidative damage, which may have been due to physiological changes associated with the parr‐smolt transformation. Erythrocytes appeared to be more sensitive to variation in dietary levels of TOCAA than liver and kidney tissues. Using the March ERPL assay results as a baseline, a TOCAA level of approximately 350–600 mg/kg diet would provide adequate protection against lipid peroxidation under most circumstances in juvenile Chinook salmon.
The effect of vitamin C supplementation in healthy dogs on antioxidative capacity and immune parameters
Authors: Hesta M. , Ottermans C. , Krammer‐Lukas S. , Zentek J. , Hellweg P. , Buyse J. , Janssens G. P. J. 
Published: February 2008

SummaryThe aim of the study was to investigate the ability of vitamin C to increase the antioxidative and immunomodulating potential in healthy dogs. Fifteen dogs were tested for the effects of orally administered vitamin E (60 mg dl‐α tocopheryl acetate) in combination with vitamin C (0, 30 or 60 mg ascorbic acid crystalline). Three treatments (0, 30, 60 mg vitamin C) were tested in a 3 × 3 cross‐over study in three periods of 36 days. Pre‐prandial blood samples were taken for analysis of vitamins C, E, A, retinyl palmitate and stearate, antioxidant status [Thiobarbituric acid reactive substances (TBARS) and uric acid], biochemical and haematological analysis. Subpopulations of lymphocytes, mitogen‐induced peripheral blood mononuclear cell proliferation (PBMC) and serum IgA and IgG concentrations were determined. There was a trend (p = 0.056) for an increased plasma vitamin C concentration by vitamin C supplementation. There was no evidence that dietary treatment altered neither the other plasma vitamin concentrations nor TBARS and uric acid concentrations nor the subpopulations of the lymphocytes except for the number of CD4+ lymphocytes that increased with vitamin C supplementation. There was no effect of vitamin C on serum IgA and IgG concentration. A significant time × treatment interaction was demonstrated on PBMC’s to pokeweed, with an increase observed by 30 mg vitamin C supplementation but a decrease by 60 mg vitamin C supplementation. There was no clear evidence for an effect of dietary vitamin C on antioxidative capacity in healthy dogs fed a diet with vitamin E concentrations well above the recommendations. Yet, a limited number of immunological parameters were slightly affected.
Starch gelatinization and physical quality of pea flakes in canine dinners as affected by soaking, steam treatment and infrared radiation
Authors: Yang S. C. , Zandstra T. , Van Der Poel A. F. B. 
Published: February 2008

SummaryCleaned, whole smooth green peas (Pisum sativum L.) were reconstituted by soaking in tap water of 40 °C (15, 20 or 25 min) and subsequently either toasted (100 °C during 1.5 min) and infrared (IR) radiated or just IR radiated. For IR radiation, a small‐scale, propane‐fired IR radiation plant was used with average residence times of 58 and 92 s respectively. After exiting the conveyor belt, peas were held for a pre‐determined period (holding: 0, 15 or 30 min respectively) in a well‐insulated container. Finally, all radiated peas were flaked (roll distance 0.75 mm) in a flaking mill located posterior to the IR plant and analysed for chemical and physical properties. Initial pea starch gelatinization degree (SGD) was 10.1% at a total starch content of 410.1 g/kg. Infrared processing during 92 s significantly improved the SGD (from 10.1% to 32.8%) of pea flakes compared to treatment during 58 s (SGD of 18.6%). The SGD was further improved with steam treatment of peas, prior to IR. For all determined parameters, no effect of holding time could be observed. Starch gelatinization degree can be improved by soaking, toasting and IR processing. The substantial improvement of SGD, however can be only obtained by a longer IR residence time as well as through toasting, prior to the IR processing. The improvements in SGD, however are paralleled by a lower durability of flakes (range 34.9% to 87.4%).
Optimizing the sensory characteristics and acceptance of canned cat food: use of a human taste panel
Authors: Pickering G. J. 
Published: February 2008

SummaryA methodology based on descriptive analysis techniques used in the evaluation of human food has been successfully refined to allow for a human taste panel to profile the flavour and texture of a range of cat food products (CFP) and their component parts. Included in this method is the development of evaluation protocols for homogeneous products and for binary samples containing both meat chunk (MC) and gravy/gel (GG) constituents. Using these techniques, 18 flavour attributes (sweet, sour/acid, tuna, herbal, spicy, soy, salty, cereal, caramel, chicken, methionine, vegetable, offaly, meaty, burnt flavour, prawn, rancid and bitter) and four texture dimensions (hardness, chewiness, grittiness and viscosity) were generated to describe the sensations elicited by 13 commercial pet food samples. These samples differed in intensity for 16 of the 18 flavour attributes, which allows for individual CFP flavour profiles to be developed. Principal components analysis (PCA) could successfully discriminate between samples within the PCA space and also reveal some groupings amongst them. While many flavour attributes were weakly correlated, a large number (describing both taste and retro‐nasal aroma qualities) were required to adequately differentiate between samples, suggesting considerable complexity in the products assessed. For both MC and GG, differences between samples for each of the texture dimensions were also found. For MC, grittiness appears to be the most discriminating textural attribute, while for GG viscosity discriminates well between samples. Meat chunks and gravy/gels differed significantly from each other in both flavour and texture. Cat food products differed in their liking ratings, although no differences were found between homogeneous, MC and GG samples, and eight flavour attributes were correlated with overall liking scores. It is now necessary to determine the usefulness and limits of sensory data gathered from human panels in describing and predicting food acceptance and preference behaviours in cats. For instance, while the sense of taste in cats appears generally similar to that of other mammals, they lack a sweet taste receptor (Li et al., 2006), which may limit the applicability of sweetness ratings obtained from humans. Modification of existing techniques used with human food research, such as external preference mapping (Naes and Risvik, 1996) may be useful. Ultimately, this may facilitate more economical and efficient methods for optimizing cat food flavour and texture and predicting the effects of composition and processing changes on cat feeding behaviour. This will require collaboration between pet food manufacturers and nutritionists, animal behaviourists and human sensory scientists. The results of this preliminary study should assist in this process.
Vitamin D receptor amounts across different segments of the gastrointestinal tract in Brown Swiss and Holstein Frisean cows of different age
Authors: Liesegang A. , Singer K. , Boos A. 
Published: February 2008

SummaryDuring different stages of lactation, different requirements of calcium have to be met depending on the milk amount. Vitamin D receptors (VDR) regulate calcium homeostasis by increasing the entry of Ca into blood from bone stores and dietary sources. The purpose of this study was to investigate if age and breed of cows influence VDR amounts across different segments of the gastrointestinal tract. Thirty‐six cows were used (18 brown swiss, 18 holstein friesan, both > 5.5 years or < 4.5 years). Tissue specimens of the intestines were collected from the cows. Formaldehyde‐fixed and microwave‐treated paraffin sections were used for VDR immunohistochemistry employing a biotinylated monoclonal rat antibody and streptavidin peroxidase technique. The results showed that nuclei and cytoplasm of enterocytes stained positively for VDRs. Strongest immunoreactions were observed in intermediate and basal glandular cells. No significant differences were observed between the different groups. Vitamin D receptors immunoreactivities were prominent in duodenal mucosa, lower in jejunum and in colon, decreased further in ileum and were lowest in caecum. Decreases in number of positively marked cells and staining intensities resulted in reduced immunoreactions. The results of this study indicate that VDR are highly expressed at the site of maximal intestinal calcium absorption. No significant influence of age and breed was observed. The animals used were not in a negative Ca balance. The cows were all in the stage of late or mid lactation. During these periods, the Ca requirements are low and the diets are high in Ca concentration; and the animals are adapted to these circumstances. Passive absorption in adult animals seems to dominate when Ca intake is adequate or high. The active absorption may play a considerably more significant role during the peripartal period, when Ca homeostatic mechanisms are challenged because of tremendous Ca demand at the initiation of lactation.
Genetic variants of the cytochrome P450 and glutathione S‐transferase associated with risk of bladder cancer in a south‐eastern Chinese population
Authors: Shao Jianfeng , Gu Min , Zhang Zhendong , Xu Zhuoqun , Hu Qiang , Qian Lixin 
Published: February 2008

Objective: To evaluate the association between genetic polymorphisms ofCYP2E1RsaI andGSTM1and development of bladder cancer in a south‐eastern Han Chinese population.Methods: We hypothesized that theCYP2E1‐1019T>A andGSTM1polymorphisms were associated with risk of bladder cancer. In a hospital‐based case‐control study of 202 case patients with newly diagnosed bladder transitional cell carcinoma and 272 cancer‐free controls frequency‐matched by the age and sex, we genotyped these two polymorphisms using a polymerase chain reaction‐restriction fragment length polymorphism method.Results: We found that theGSTM1null genotype was associated with an increased risk of bladder cancer (adjusted odds ratio [OR] = 1.73, 95% confidence interval [CI] = 1.17–2.56) compared with those with the non‐null genotype, but theCYP2E1‐1019T>A polymorphisms did not show any association. In the stratification analysis of theGSTM1polymorphism, we found that the increased risk was more pronounced among subgroups aged ≤60 years (OR = 2.02, 95% CI = 1.08–3.77), smokers (OR = 1.94, 95% CI = 1.11–3.38) and non‐drinkers (OR = 3.86, 95% CI = 1.28–11.60).Conclusion: GSTM1polymorphism (but notCYP2E1RsaI polymorphism) appears to contribute to the etiology of bladder cancer in a south‐eastern Chinese population.