bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stream macroinvertebrate occurrence along gradients in organic pollution and eutrophication
Authors: FRIBERG NIKOLAI , SKRIVER JENS , LARSEN SØREN E. , PEDERSEN MORTEN L. , BUFFAGNI ANDREA 
Published: June 2009

Summary1. We analysed a large number of concurrent samples of macroinvertebrate communities and chemical indicators of eutrophication and organic pollution [total‐P, total‐N, NH4–N, biological oxygen demand (BOD5)] from 594 Danish stream sites. Samples were taken over an 11‐year time span as part of the Danish monitoring programme on the aquatic environment. Macroinvertebrate communities were sampled in spring using a standardised kick‐sampling procedure whereas chemical variables were sampled six to 24 times per year per site. Habitat variables were assessed once when macroinvertebrates were sampled.2. The plecopteran Leuctra showed a significant negative exponential relationship (r2 = 0.90) with BOD5 and occurred at only 16% of the sites with BOD5 above 1.6 mg L−1. Sharp declines with increasing BOD5 levels were found for the trichopteran families Sericostomatidae and Glossosomatidae although they appeared to be slightly less sensitive than Leuctra. Other plecopterans such as Isoperla showed a similar type of response curve to Leuctra (negative exponential) but occurred at sites with relatively high concentrations of BOD5 up to 3–4 mg L−1. In contrast, the response curve of the isopod Asellus aquaticus followed a saturation function reaching a plateau above 3–4 mg L−1 BOD5 and the dipteran Chironomus showed an exponential increase in occurrence with increasing BOD5 concentration.3. Macroinvertebrate occurrence appeared to be related primarily to concentrations of BOD5, NH4–N and total‐P whereas there were almost no relationships to total‐N. Occurrence of a number of taxa showed a stronger relationship to habitat conditions (width and substrate) than chemical variables.4. Important macroinvertebrate taxa are reduced at concentrations of BOD5 that are normally perceived as indicating unimpacted stream site conditions. Our results confirmed sensitivity/tolerance patterns used by existing bioassessment systems only to some degree.
Estimating the near surface amplification factor to minimize earthquake damage: a case study at West Wadi Hagoul area, Egypt
Authors: Mohamed Adel M.E. 
Published: June 2009

ABSTRACTThe damage caused by earthquake occurrences in different localities all over the world necessitates the evaluation of the underground and/or sub‐soil structure for strategic projects. The case study is the proposed area for a new factory construction that lies 3 km west of Suez Cement factory, in the area between Kottamiya and Ain Sokhna. The shallow seismic refraction survey was carried out through 10 major lines (grid lines), comprising 30 seismic profiles. The microtremor measurements were done at 25 locations at the grid intersection points. The obtained compressional (P) and horizontal shear (SH) wave velocities, with the horizontal to vertical (H/V) spectral ratios, are used to deduce the subsurface structures, to evaluate the elastic and dynamic properties and the transfer function at both the surface and bedrock. The results illustrate that there is a good correlation between the fundamental frequencies deduced through the theoretical transfer function and the H/V spectral ratio. The maximum value of ground motion amplification factor of the study area is 3.3 at a corresponding frequency of 7.8 Hz.
Time‐related changes of the intestinal morphology of Atlantic salmon, Salmo salar L., at two different soybean meal inclusion levels
Authors: Urán P A , Schrama J W , Rombout J H W M , Taverne‐Thiele J J , Obach A , Koppe W , Verreth J A J 
Published: June 2009

AbstractSoybean meal (SBM) induces enteritis in the distal intestine of Atlantic salmon. The present study assesses the effects of SBM concentrations on the kinetics of the enteritis process. Fish of 300 g, kept at 12 °C, were fed diets with different SBM inclusions: 0%, 10% and 20% SBM for 57 days. Samples of the distal intestine of five fish per treatment were taken for histological and electron microscopical analysis. A semi‐quantitative scoring system was used to assess the degree of the morphological changes induced by SBM feeding in the distal intestinal epithelium. The first signs of enteritis appeared earlier in the salmon fed the 20SBM diet than in those fed the 10SBM diet. Thereafter, the condition increased steadily, displaying no signs of recovery. Furthermore, at the lower concentration, the process marking the onset of enteritis began more gradually than at the higher concentration and it displayed a tendency to stabilize after 13–20 days of continuous feeding. Electron microscopy indicated that the endocytosis process was hampered at day 3 of 20SBM and at 7 days of 10SBM. Furthermore, a strong reduction of microvilli was already evident after 7 days of 20SBM feeding, thus indicating a decreased uptake capacity of the distal enterocytes. In addition, transformation and migration of eosinophilic granulocytes was observed, which, in combination with the lysozyme C immunoreactivity supports their protective role during the inflammatory process in the distal gut of Atlantic salmon. It can be concluded that the severity of enteritis and its kinetics are concentration‐dependent, showing no signs of recovery during feeding with diets containing SBM.
Influence of Maternal Hyperglycaemia on Cord Blood Mononuclear Cells in Response to Diabetes‐associated Autoantigens
Authors: Stechova K. , Spalova I. , Durilova M. , Bartaskova D. , Cerny M. , Cerna M. , Pithova P. , Chudoba D. , Stavikova V. , Ulmannova T. , Faresjö M. 
Published: June 2009

AbstractPerfect maternal diabetes compensation is crucial for the outcome of the baby. However, little is known how hyperglycaemia influences the specific immune response. Furthermore, babies of type 1 diabetes (T1D) mothers have less risk of development T1D than babies with a T1D father. This study aimed to analyze the effect of maternal hyperglycaemia on newborns with focus on the response to diabetes‐associated autoantigens. Populations: (1) Newborns of T1D mothers split into groups according to maternal diabetes compensation during the 3rd trimester: perfect (n = 15) or acceptable (n = 25) compensation. (2) newborns with T1D father (n = 12) (3) newborns with a mother treated for either gestational or type 2 diabetes (n = 10) (4) control newborns (n = 25). Spontaneous as well as diabetes‐associated autoantigen‐stimulated production of 23 cytokines and chemokines were tested using protein microarray. In addition, the influence of glucose on cytokine and chemokine responsiveness was analyzed in vitro. The study groups differed in their spontaneous as well as stimulated cytokine and chemokine spectra. A prominent Th1 response (high IFN‐gamma) from autoantigen stimulation was observed especially in babies of T1D fathers (P = 0.001) and also in mothers with perfect diabetes compensation during the 3rd trimester (P = 0.016) in comparison with control newborns. By contrast, cord blood mononuclear cells cultivated in vitro in high glucose concentration decreased the diabetogenic stimulated Th1 cytokine response. Maternal ‘sweet’ as well as ‘autoimmune environment’ may both lead to lower occurrence of T1D within their offspring. Further studies will reveal the exact immunological mechanism of this observation.
Homologous recombination‐mediated knock‐in targeting of the MET1a gene for a maintenance DNA methyltransferase reproducibly reveals dosage‐dependent spatiotemporal gene expression in rice
Authors: Yamauchi Takaki , Johzuka‐Hisatomi Yasuyo , Fukada‐Tanaka Sachiko , Terada Rie , Nakamura Ikuo , Iida Shigeru 
Published: June 2009

SummaryAlthough homologous recombination‐promoted knock‐in targeting to monitor the expression of a gene by fusing a reporter gene with its promoter is routine practice in mice, gene targeting to modify endogenous genes in flowering plants remains in its infancy. In the knock‐in targeting, the junction sequence between a reporter gene and an endogenous target promoter can be designed properly, and transgenic plants carrying an identical and desired knock‐in allele can be repeatedly obtained. By employing a reproducible gene‐targeting procedure with positive–negative selection in rice, we were able to obtain fertile transgenic knock‐in plants with the promoterless GUS reporter gene encoding β‐glucuronidase fused with the endogenous promoter of MET1a, one of two rice MET1 genes encoding a maintenance DNA methyltransferase. All of the primary (T0) transgenic knock‐in plants obtained were found to carry only one copy of GUS, with the anticipated structure in the heterozygous condition, and no ectopic events associated with gene targeting could be detected. We showed the reproducible, dosage‐dependent and spatiotemporal expression of GUS in the selfed progenies of independently isolated knock‐in targeted plants. The results in knock‐in targeted plants contrast sharply with the results in transgenic plants with the MET1a promoter‐fused GUS reporter gene integrated randomly in the genome: clear interindividual variation of GUS expression was observed among independently obtained plants bearing the randomly integrated transgenes. As our homologous recombination‐mediated gene‐targeting strategy with positive–negative selection is, in principle, applicable to modify any endogenous gene, knock‐in targeting would facilitate basic and applied plant research.
RRS1 and RPS4 provide a dual Resistance‐gene system against fungal and bacterial pathogens
Authors: Narusaka Mari , Shirasu Ken , Noutoshi Yoshiteru , Kubo Yasuyuki , Shiraishi Tomonori , Iwabuchi Masaki , Narusaka Yoshihiro 
Published: June 2009

Summary Colletotrichum higginsianum is a fungal pathogen that infects a wide variety of cruciferous plants, causing important crop losses. We have used map‐based cloning and natural variation analysis of 19 Arabidopsis ecotypes to identify a dominant resistance locus against C. higginsianum. This locus named RCH2 (for recognition of C. higginsianum) maps in an extensive cluster of disease‐resistance loci known as MRC‐J in the Arabidopsis ecotype Ws‐0. By analyzing natural variations within the MRC‐J region, we found that alleles of RRS1 (resistance to Ralstonia solanacearum 1) from susceptible ecotypes contain single nucleotide polymorphisms that may affect the encoded protein. Consistent with this finding, two susceptible mutants, rrs1‐1 and rrs1‐2, were identified by screening a T‐DNA‐tagged mutant library for the loss of resistance to C. higginsianum. The screening identified an additional susceptible mutant (rps4‐21) that has a 5‐bp deletion in the neighboring gene, RPS4‐Ws, which is a well‐characterized R gene that provides resistance to Pseudomonas syringae pv. tomato strain DC3000 expressing avrRps4 (Pst‐avrRps4). The rps4‐21/rrs1‐1 double mutant exhibited similar levels of susceptibility to C. higginsianum as the single mutants. We also found that both RRS1 and RPS4 are required for resistance to R. solanacearum and Pst‐avrRps4. Thus, RPS4‐Ws and RRS1‐Ws function as a dual resistance gene system that prevents infection by three distinct pathogens.
Weed occurrence on pavements in five North European towns
Authors: MELANDER B , HOLST N , GRUNDY A C , KEMPENAAR C , RIEMENS M M , VERSCHWELE A , HANSSON D 
Published: June 2009

SummaryWeeds on pavements in urban areas are unwanted mainly because they cause an untidy appearance or sometimes structural damage. Glyphosate has been the principal weed control method for years, but policies in several European towns have changed to lower dependence on herbicides. Instead, less effective and more species‐dependent non‐chemical methods are used, but little is known about the pavement flora. Consequently, we surveyed the flora on pavements in five North European towns [Braunschweig (DE), Malmö (SE), Næstved (DK), Royal Leamington Spa (UK) and Wageningen (NL)] by recording weed species and their coverage in 56 recording points randomly placed in each town. Weeds were recorded at several dates in 2005 and 2006 and no weed control was applied apart from sweeping. Weed coverage increased during the survey (averaging 1.4% in late 2006) and was highest in the towns having the strictest policies limiting herbicide use. Most coverage (averaging 2%) was found along the pavement edge away from the road. Poa annua was the most frequently recorded species, followed by bryophytes (mainly mosses), Sagina procumbens and perennial grasses. Grasses and some other species frequently found, notably Taraxacum officinale, should receive particular attention when planning a non‐chemical weed control campaign on pavements.
Multiple introductions are responsible for the disjunct distributions of invasive Parthenium hysterophorus in China: evidence from nuclear and chloroplast DNA
Authors: TANG S Q , WEI F , ZENG L Y , LI X K , TANG S C , ZHONG Y , GENG Y‐P 
Published: June 2009

Summary Parthenium hysterophorus is an invasive weed native to tropical and subtropical America. Since its introduction into China in 1926, this weed has been limited to southern areas (18°–25°N). However, new populations were recently reported in Shandong (35°N). The origin of this geographically isolated population remains unclear. In this study, we used inter simple sequence repeat and chloroplast DNA sequence markers (trnQ‐5’rps16) to investigate the genetic structure of 18 invading populations of P. hysterophorus and to examine the genetic relationship of Shandong and southern populations. Our data show that Shandong population is genetically different and has apparently higher levels of genetic diversity than most populations in southern China. Both neighbour‐joining clustering and principal coordination analysis clearly separated Shandong from other populations. Chloroplast DNA sequence analysis further confirmed that the Shandong population was characterised by a unique haplotype that was not found in southern populations. We conclude that the population in Shandong may have been independently introduced from areas outside China. As P. hysterophorus has a broad potential distribution in China, attention should be paid to both international and domestic quarantine to prevent new introductions and curtail the possible hybridisation and gene flow between populations in different regions.
Carbon and Nitrogen Transport during Grain Filling in Rice Under High‐temperature Conditions
Authors: Ito S. , Hara T. , Kawanami Y. , Watanabe T. , Thiraporn K. , Ohtake N. , Sueyoshi K. , Mitsui T. , Fukuyama T. , Takahashi Y. , Sato T. , Sato A. , Ohyama T. 
Published: June 2009

AbstractRice (Oryza sativa cv. Koshihikari) seedlings were grown in a sandy dune soil in pots with a basal dressing of N (0.5 g N), P and K. Two N treatments were applied, a +N treatment in which a top dressing of 15N‐labeled 0.5 g N was supplied on July 20 and a −N treatment in which no additional fertilizer was supplied. During the grain‐filling stage from August 6 to 13, plants were subjected to one of three temperature treatments; controlled low temperature, LT (day/night 28/23 °C), controlled high temperature, HT (35/30 °C) and uncontrolled glasshouse temperature, UT (day/night averages, 38/26 °C). All plants were then exposed to 13CO2 for 1 h on August 11 in a growth chamber at 25 °C. On August 13, all plants were harvested and the 13C and 15N abundances and starch and sugar concentrations in the ears, shoots and roots were determined. The 13C content of the ear was lower in UT than in LT irrespective of the +N or −N treatment. The translocation of 15N to the ears was also slightly depressed in UT compared with LT. Under high‐temperature conditions (HT and UT), the starch content per plant was reduced for −N, but for +N, it was not significantly different among the temperature treatments. A high accumulation of sucrose was observed in all plant parts under UT conditions. It is suggested that extreme high day temperatures during the grain‐filling period may reduce starch synthesis in the grains and, especially so under N‐deficient conditions. High temperatures also induce an accumulation of sucrose and a decrease in carbon and nitrogen transport from the shoots to the ears via the phloem.
Enforced herbivory on Canavalia ensiformis and Tithonia diversifolia and its effects on leaf‐cutting ants, Atta cephalotes
Authors: Valderrama‐Eslava E. I. , Montoya‐Lerma J. , Giraldo C. 
Published: June 2009

AbstractHerbivory by leaf‐cutting ants can lead to serious problems for agricultural and forest systems in the Neotropics. Chemical insecticides are the major, if not only, control tactic, but the efficiency of this approach is questionable. Moreover, continued reliance on insecticidal control leads to environmental damage and risks to human and animal health. Developing alternative management tactics for leaf‐cutting ants is thereby a justifiable and sensible need. Recent findings suggest that the Mexican sunflower, Tithonia diversifolia and the jackbean, Canavalia ensiformis, have detrimental effects on leaf‐cutting ant populations under laboratory and field conditions. It is unclear, however, whether those effects involve the development and growth of the ant’s symbiotic fungus, the ants or both. To address this question, an experiment was conducted on 18 artificial Atta cephalotes colonies maintained with three feeding treatments: a control (mango, Mangifera indica), T. diversifolia and C. ensiformis. Six repetitions of each treatment were assigned to the colonies in a completely randomized design and evaluated over a period of 2 months under laboratory conditions. Both T. diversifolia and C. ensiformis negatively altered growth of the symbiotic fungus Leucoagaricus gongilophorus and thereby affected the survival of A. cephalotes. The greatest reduction in fungus size (up to 100%) and the highest ant mortality (83.3%) were observed in colonies fed on T. diversifolia, but not until 45 days after the start of the experiment. In colonies fed on C. ensiformis, the greatest reduction in fungus size (95.3%) and the highest ant mortality (66.6%) were reached at 57 days. During the course of the study, no negative effects were observed in the control colonies, which displayed a consistently healthy symbiotic fungus and low rate of ant mortality (16.6%). Based on these results, plants of both T. diversifolia and C. ensiformis offer promise for the biological control of A. cephalotes populations.
Life‐history traits of the edible stinkbug, Encosternum delegorguei (Hem., Tessaratomidae), a traditional food in southern Africa
Authors: Dzerefos C. M. , Witkowski E. T. F. , Toms R. 
Published: June 2009

AbstractLittle is known of the life history of the edible stinkbug, Encosternum delegorguei, although it is an important food for people living in north‐eastern South Africa and southern Zimbabwe. The present study aimed to establish key elements influencing long‐term sustainable harvesting. Outdoor insectaries of two sizes were constructed to observe: daily activity, utilization of plants, copulation, oviposition, eclosion and survival from May 2006 to February 2007. The rest of the annual life cycle was observed in the field in March and April 2007 and identified as univoltine. In autumn (May) E. delegorguei entered reproductive diapause and aggregated within the escarpment mist‐belt where it survived the winter on vapour condensation without feeding. Monthly dissections showed that abdominal fat content was highest in June. In spring (September) E. delegorguei fed on sap of the trees Combretum imberbe, Combretum molle, Peltophorum africanum, to a lesser degree on Dodonaea viscosa and the grass Pennisetum clandestinum. Copulation occurred in October and November. An overall total of 1752 E. delegorguei eggs were laid by 103 females and incubation time averaged 18.7 ± 9.0 days (range 7–37) at outdoor temperature ranging from 11°C to 25°C. The mean number of eggs in 64 egg masses was 27.4 ± 13.9 (range of 2–56 eggs). Shade cloth (68.8%) was the most commonly used substrate for depositing eggs followed by P. clandestinum (12.5%), C. imberbe (7.8%), P. africanum (6.3%), D. viscosa (1.6%), C. molle (1.6%) and C. erythrophyllum (1.6%). The parasitoid wasp, Anastatus sp. (Hymenoptera: Eupelmidae) infected 57% of the eggs deposited by captive females. Availability of food plants in combination with parasitoid threat may be a reason for seasonal migration between overwintering sites within the mist‐belt and summer oviposition sites. Diminishing harvests could be attributed to fuelwood harvesting of food plants in the summer sites.
Simvastatin inhibits angiotensin II‐induced cardiac cell hypertrophy: Role of Homer 1a
Authors: Guo Wan‐Gang , Su Fei‐Fei , Yuan Li‐Jun , Yang Guo‐Dong , Shi Xiao‐Qin , Li Ruo‐Yu , Shu Qing , Liu Xiong‐Tao , Lu Zi‐Fan , Zheng Qiang‐Sun 
Published: June 2009

Summary

The scaffolding protein Homer 1a is constitutively expressed in the myocardium, although its function in cardiomyocytes remains poorly understood. The aim of the present study was to investigate Homer 1a expression in hypertrophic cardiac cells and its role in angiotensin (Ang) II‐induced cardiac hypertrophy.
After serum starvation for 24 h, cells were treated with 1 μmol/L simvastatin, 100 nmol/L angiotensin (Ang) II or their combination added to Dulbecco's modified Eagle's medium containing 0.5% serum. For combination treatment with AngII plus simvastatin, cells were exposed to simvastatin 12 h before the addition of AngII to the medium and cells were then incubated in the presence of both drugs for a further 24 h. Western blotting was used to determine Homer 1a protein expression. Hypertrophy was evaluated by determining the protein content per cell.
Homer 1a protein levels were upregulated following AngII‐induced hypertrophy in H9C2 cells and neonatal rat cardiomyocytes, and these increases were augmented by simvastatin pretreatment. Concomitantly, simvastatin pretreatment inhibited extracellular signal‐regulated kinase (ERK) 1/2 phosphorylation and AngII‐induced hypertrophy.
The inhibitory effects of simvastatin against AngII‐induced hypertrophy were attenuated by Homer 1a silencing, suggesting that simvastatin suppresses cardiac hypertrophy in a Homer 1a‐dependent manner. Furthermore, AngII‐induced hypertrophy and ERK1/2 phosphorylation in neonatal rat cardiomyocytes were significantly inhibited following the overexpression of Homer 1a using an adenovirus.
These results suggest a possible role for Homer 1a in inhibiting cardiac hypertrophy perhaps in part through inhibition of ERK1/2 activation.