bluuebunny/crossref_metadata_2025_split huggingface dataset:
Palaeoecology of two lake basins from Disko, West Greenland
Authors: Bennike Ole 
Published: February 2007

AbstractThe macrofossils, lithology and chronology of two lake basins on Disko in central West Greenland have been investigated. Both lakes were isolated from the sea in the mid‐Holocene as a result of relative land uplift. A marine‐brackish‐limnic sequence was recovered from the Qivittut Lake. The marine fauna is unusually diverse, whereas the brackish water fauna consists only of few species. Immediately after isolation the lake passed through a short‐lived eutrophic phase, after which stable, mesotrophic conditions were established. From the second lake basin, the Fortunebay Lake, only limnic sediments were recovered. This lake record demonstrates that rather stable conditions have persisted since mid‐Holocene times. Both lakes show anomalously high accumulation rates.
Palynology of organic beds below Devensian glacigenic sediments at Pen‐y‐bryn, Gwynedd, North Wales
Authors: Chambers Frank M. , Addison Kenneth , Blackford Jeffrey J. , Edge Martin J. 
Published: February 2007

AbstractPollen diagrams from organic facies overlain by glacigenic sediments at Pen‐y‐bryn, North Wales (53°7′N, 4°16′W), suggest that it is the first locality in the British Isles to provide evidence for several Devensian interstadials prior to Devensian stadial glaciation(s). The evidence is not, however, unequivocal. At least two main episodes of organic sedimentation are indicated, separated by an interval of uncertain duration. One eposide records a Pinus‐Picea‐Betula forest. A second, possibly later, event, with tree pollen less than 10% of total land pollen (TLP), suggests a cool, largely unforested environment. A third episode, with tree pollen up to 25% of TLP, may be related to the latter or be of intermediate age, whereas a fourth and later episode of organic accumulation may be of reworked material. Radiocarbon dating of organic deposits and of a wood macrofossil enclosed in basal till is inconclusive, as is preliminary uranium‐series dating. The principal biogenic episodes may correlate with Oxygen Isotope Substages 5c and 5a, but as the pollen records reflect facies floras, the correlation remains tentative; it is also possible that other temperate periods are recorded. Further resolution of the chronostratigraphy is required to help clarify the problematic correlation of interstadial and stadial events in northwest Europe and to correlate more accurately the biogenic and glacigenic facies at Pen‐y‐bryn with their Pleistocene equivalents elsewhere.
Fluctuations of the South Patagonian Ice‐field during the last glaciation and the Holocene
Authors: Marden Christopher J. , Clapperton Chalmers M. 
Published: February 2007

AbstractMapping along a transect from the southeastern margin of the South Patagonian Ice‐field in Torres del Paine National Park (Chile) to the limits of fresh moraines of the last glacial cycle indentified eight glacier advances. The four younger ones have been dated by dendrochronology, tephrochronology and radiocarbon dating. Although the bases of 10 m deep bogs were sampled, close limiting radiocarbon dates were not obtained because bog formation in this rain‐shadow area appears not to have commenced until ca.12000 yr ago. The outermost Little Ice Age moraine formed during the seventeenth century and three inner ones were deposited around ad 1805, 1845 and after 1890. Densely vegetated older moraines contiguous with Little Ice Age deposits are possibly of late Holocene age. Tephra from the eruption of Reclus volcano at ca. 11 880 yr BP was incorporated by a readvance that deposited large multiple moraines 10–16 km from the modern ice‐front; the oldest basal peat found inside the moraine has been dated to ca. 9200 yr BP. These bracketing dates indicate that some eastern outlet glaciers of the ice‐field advanced at a time when some western tidewater outlet glaciers terminated inside their modern limits. This questions the view of J. H. Mercer and other that Patagonian glaciers did not readvance during the late‐glacial interval. A stadial event also occurred when the glaciers were some 18–20 km from their modern positions and is closely dated to ca. 11880 yr BP because Reclus pumice flushed down‐glacier forms thick upper beds in outwash deltas deposited in proglacial lakes.The four older moraines pre‐date the late‐glacial eruption of Reclus but are not dated closely. Comparison of their spatial extent with well‐dated moraines in the Chilean Lakes Region suggests that they may mark advances culminating at ca. 14000 yr BP, ca. 20000 yr BP and earlier.
The intra‐Saalian interstadial floras of the Chojny Formation of Belchatów, central Poland
Authors: Krzyszkowski D. , Nita M. 
Published: February 2007

AbstractThe Saalian sequence of Belchatów, central Poland, is exceptionally thick and complete. Five tills, two from the older Saalian (Odranian, Drenthe) and three from the younger Saalian (Wartanian, Warthe), which are separated by the fluvial Chojny Formation, have been identified. The Saalian sequence at Bełchatów is underlain by Holsteinian and overlain by Eemian sequences, both palaeobotanically analysed. The Chojny Formation contains deposits of meandering (lower member) and braided (upper member) rivers, with occasional aeolian deposits. The lower member of the formation contains numerous organic layers. Pollen analysis indicates temperate (sub‐boreal) to cold (sub‐arctic) climatic conditions, with coniferous to mixed forests in the optimum phase of the interstadial. The interstadial floras of the Chojny Formation are interpreted as representing the intra‐Saalian Pilica Interstadial. Profiles from Belchatów are designated as the stratotype profiles of this substage. The data from Bełchatów show clearly that reforestation occurred between the major advances of the Saalian ice sheet, although only interstadial rank, not interglacial, may be inferred from the pollen data.
Late Weichselian to early Holocene litho‐ and biostratigraphy in the Devil's Hole area, central North Sea, and its relation to glacial isostasy
Authors: Ekman Sten S. R. 
Published: February 2007

AbstractThe 6‐m‐long British Geological Survey vibrocore 56+01/170 from the Devil's Hole area, central North Sea, comprises glaciomarine and marine sediments of Late Weichselian and Holocene age. Besides the foraminiferal, pollen and AMS 14C data presented in this study, amino acid and ostracod data exist for the core.The accumulation of the sediment in the core began ca. 15.7 14C ka BP on an erosional surface on overconsolidated Saalian sediment. When the lower part of the core (facies 1) accumulated the core area is interpreted to have been around 40 m lower than present. This interpretation is based on two assumptions; first, that the sediment is now ca. 20 m above the global sea level at the time of deposition, and second, that the marine microfaunal content reflects a water depth of about 20 m at that time. Crustal downflexure caused by Late Weichselian glacial loading of the core area is considered as the most plausible explanation of this difference. Glacial overriding would also explain the overconsolidation of the underlying Saalian sediment, the erosional surface on the Saalian sediment and the absence of Weichselian sediment older than ca. 15.7 ka BP at the core site.Indications of a regressional trend, with a minimum age of 12.1 ka BP, support the suggestion that the Devil's Hole area was glaciated during the Weichselian, as the fall in sea‐level at that time probably reflects local isostatic rebound.
Effects of plant species, stage of maturity and additive on the feeding value of whole‐crop cereal silage
Authors: Nadeau Elisabet 
Published: February 2007

AbstractThis experiment aimed to study the effects of plant species, stage of maturity, additive and their interactions on yield, chemical composition and fermentation characteristics of whole‐crop cereal silage. Barley, triticale, oats and spring wheat were harvested at the early milk stage or at the early dough stage of maturity in 2002 and 2003 with three field replicates of the plant species within each year. Proens™ (Perstorp Inc, Perstorp, Sweden), which contained 2/3 formic acid and 1/3 propionic acid, was applied at 4 L tonne−1 herbage and Lactisil 200® NB (Medipharm Inc, Kågeröd, Sweden), which contained Lactobacillus plantarum, Enterococcus faecium, Pediococcus acidilactici, Lactococcus lactis, cellulase and sodium benzoate, was applied at 200 000 colony‐forming units g−1 herbage, and both applications were compared to untreated silage. Unwilted herbage, chopped at 12 mm length, was ensiled in 4‐L laboratory silos for 90 days. Barley had more starch whereas triticale had more sugar and crude protein but less neutral detergent fibre than other species (P < 0.001). Barley and triticale had less acid detergent fibre and lignin but greater in vitro organic matter (OM) digestibility than oats and spring wheat (P < 0.0001). Averaged over maturity stages, wheat had a greater yield of digestible OM than barley and oats (P < 0.0001). Yield of digestible OM and concentration of starch increased whereas sugar concentration decreased with later maturity stage (P < 0.0001). Late harvest increased the risks for high levels of butyric acid in silage when no additives were used (P = 0.002). Additives resulted in increased lactic:acetic acid ratios but decreased protein degradation and DM losses (P < 0.0001). Acid treatment was more effective than inoculation to degrade starch and to decrease protein degradation and DM losses during ensiling (P < 0.0001). Harvest at the early milk stage of maturity resulted in more lactic acid and a lower pH than harvest at the early dough stage of maturity (P < 0.0001). When considering both maximal yield of digestible organic matter and good silage quality, triticale, wheat or barley silage harvested at the early dough stage of maturity and ensiled with acid or inoculant is suggested. Copyright © 2007 Society of Chemical Industry
Impact of sorghum processing on phytate, phenolic compounds and in vitro solubility of iron and zinc in thick porridges
Authors: Kayodé AP Polycarpe , Linnemann Anita R , Nout Martinus JR , Van Boekel Martinus AJS 
Published: February 2007

AbstractThis study focussed on the impact of process variables on levels of phytate and phenolic compounds, and in vitro solubility of iron (Fe) and zinc (Zn) in sorghum porridges, a major staple in semi‐arid tropics. The aim was to identify practices that enhance the mineral availability in this type of staple food. We studied the example of the West African porridge ‘dibou’ for which the processing methods involve grain cleaning, milling, sieving and cooking. Regional variations occur in the process, particularly in the cleaning which may be done wet or dry; sieving may be omitted in certain locations. Cleaning reduced the phytate content of the grain by 24–39%, while milling, sieving and cooking had no significant effect on phytate. Phenolic compounds measured as levels of reactive hydroxyl groups, remained constant after cleaning, milling and sieving, but significantly decreased by 38–65% after cooking. The Fe solubility tended to increase after cleaning but was drastically reduced due to cooking, and so was the soluble Zn. Levels of total phenolic compounds highly correlated with the Fe and Zn solubility (r2 = 0.73 and 0.82, respectively). Phenolic reaction products formed during the cooking process are presumably related with the extensive browning phenomenon observed in the dibou porridge, and with the reduction observed in Fe and Zn solubility. Copyright © 2007 Society of Chemical Industry
Physical properties of some intensively cultivated soils of Ireland amended with spent mushroom compost
Authors: Curtin J. S. , Mullen G. J. 
Published: February 2007

AbstractIn this paper, spent mushroom compost (SMC), a by‐product of the mushroom industry, is proposed as a suitable organic amendment for soil structure restoration. A 4‐month incubation pot trial was conducted in which fresh and composted SMC was amended at three different rates (50, 100 and 200 t ha−1) to a range of structurally degraded tillage soils (n = 10). Soil OC content and aggregate stability as determined by the three disrupting tests of the Le Bissonnais method (fast‐wetting, slow‐wetting and mechanical breakdown) were investigated. Applications of 50, 100 and 200 t ha−1 fresh SMC increased the OC content by 2·71 per cent, 2·69 per cent and 2·49 per cent respectively, while amendments of composted SMC increased the OC content by 3·28 per cent, 2·94 per cent and 2·87 per cent for each application rate, respectively. The effect of SMC on aggregate stability was generally positive and statistically significant in most soils. However, in soils 3 and 4 an application rate of 200 t ha−1 SMC decreased the aggregate stability, on average, by 15 per cent, in comparison to the control, for the fast‐wetting test. Aggregate stability was strongly controlled by the inherent OC content of the study soils; that is, the OC content prior to SMC addition. A positive correlation coefficient was also evident for the dithionite‐extractable iron, most pronounced for slow‐wetting and mechanical breakdown treatments (r = 0·844 and r = 0·817 respectively). It is clear from this research that SMC amendments have the capacity to improve soil structural stability. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis and Properties of Novel Fluorinated Poly(phenylene‐co‐imide)s
Authors: Li Wenmu , Zhang Suobo , Chen Guang , Zhang Quanyuan 
Published: February 2007

AbstractA new class of high‐performance materials, fluorinated poly(phenylene‐co‐imide)s, were prepared by Ni(0)‐catalytic coupling of 2,5‐dichlorobenzophenone with fluorinated dichlorophthalimide. The synthesized copolymers have high molecular weights ($\overline M _{\rm w}$ = 5.74 × 104–17.3 × 104 g · mol−1), and a combination of desirable properties such as high solubility in common organic solvent, film‐forming ability, and excellent mechanical properties. The glass transition temperature (Tgs) of the copolymers was readily tuned to be between 219 and 354 °C via systematic variation of the ratio of the two comonomers. The tough polymer films, obtained by casting from solution, had tensile strength, elongation at break, and tensile modulus values in the range of 66.7–266 MPa, 2.7–13.5%, and 3.13–4.09 GPa, respectively. The oxygen permeability coefficients ($P_{{\rm O}_{\rm 2} }$) and permeability selectivity of oxygen to nitrogen ($P_{{\rm O}_{\rm 2} } /P_{{\rm N}_{\rm 2} }$) of these copolymer membranes were in the range of 0.78–3.01 barrer [1 barrer = 10−10 cm3 (STP) cm/(cm2 · s · cmHg)] and 5.09–6.25, respectively. Consequently, these materials have shown promise as engineering plastics and gas‐separation membrane materials.magnified image
Synthesis, Characterization, and Properties Evaluation of Poly[(N‐isopropylacrylamide)‐co‐ester]s
Authors: Ren Liqun , Agarwal Seema 
Published: February 2007

AbstractCopolymerization behavior of cyclic ketene acetal like 5,6‐benzo‐2‐methylene‐1,3‐dioxepane (BMDO) with N‐isopropylacrylamide (NIPAAm) is studied by free radical polymerization. Structural characterization is done using 1D and 2D NMR techniques. Under optimized reaction conditions, quantitative ring‐opening of BMDO took place during the copolymerizations leading to the formation of poly(NIPAAm‐co‐ester)s. The reactivity ratios for the copolymerization of BMDO and NIPAAm were determined using Kelen–Tüdõs method and found to be rBMDO = 0.11 and rNIPAAm = 7.31. Copolymers with low mol‐% of BMDO were found to be soluble in water and also showed hydrolytic degradability. Different degradable copolymers could be generated with varied glass transition temperatures and lower critical solution temperatures (LCSTs).magnified image
Study of Novel PU‐Type Polymeric Photoinitiators Comprising of Side‐Chain Benzophenone and Coinitiator Amine: Effect of Macromolecular Structure on Photopolymerization
Authors: Wei Jun , Wang Hongyu , Jiang Xuesong , Yin Jie 
Published: February 2007

AbstractThree PU‐type polymeric photoinitiators containing side‐chain benzophenone and coinitiator amine, PUSBA‐h, PUSBA‐t and PUSBA‐i, were synthesized via polycondensation of 3,5‐diamino‐4′‐thiophenylbenzophenone, different diisocyanates and N‐methyldiethanolamine. FT‐IR, 1H NMR and GPC analyses confirm the structures of all polymers. The UV‐vis spectra of polymeric photoinitiators are similar and all exhibit the maximal absorption near 320 nm. ESR spectra show PUSBA‐h and PUSBA‐t can efficiently generate free radicals. The photopolymerization of trimethylolpropane triacrylate and the PU prepolymer, initiated by these polymeric photoinitiators, was studied by photo‐DSC. The results indicate that the macromolecular structure has an important effect on photopolymerization, and different photoinitiators exhibit different behavior towards different monomers: PUSBA‐t is the most efficient for TMPTA and PUSBA‐h is the most efficient for PU prepolymer. The final conversion for the photopolymerization of PU prepolymer initiated by PUSBA‐h is greater than 97%.magnified image
Predisposing factors of restless legs syndrome in pregnancy
Authors: Tunç Tuğba , Karadağ Yeşim Sücüllü , Doğulu Funda , İnan Levent E. 
Published: February 2007

AbstractThe occurrence of restless legs syndrome in pregnancy is well known. However, the mechanism of this association is unclear. In this study, we aimed to identify the factors that predispose women to have restless legs syndrome during pregnancy. A total of 146 pregnant women were included in the study. Patients were asked questions regarding demographic characteristics, complications of pregnancy, medical therapy (vitamin and iron intake), sleep disorders, muscle cramps, and excessive daytime sleepiness. Electroneurography, routine blood biochemistry tests, complete blood count, and thyroid function tests were performed and vitamin B12, folic acid, serum iron, iron‐binding capacity, ferritin, iron saturation, prolactin, estradiol, and progesterone were measured. Of the participants, 38 were diagnosed as having restless legs syndrome. In women with restless legs syndrome, additional medical problems, night cramps, and excessive daytime sleepiness were more frequent. In women without restless legs syndrome, serum hemoglobin levels were significantly higher and the use of supplemental iron or vitamins was greater. Among the women with restless legs syndrome, progesterone levels were slightly higher but this difference was not statistically significant. In summary, in this study, lower hemoglobin levels and supplementation deficits of iron and vitamins were found be the risk factors for restless legs syndrome in pregnancy. © 2007 Movement Disorder Society
Continuous locked suture technique for arterial anastomosis in rat small bowel transplantation
Authors: Wang Jian , Ma Hao , Zhang Haiyun , Lu Bin , Wang Jinhua , Wang Zhenlong , Li Yousheng , Li Jieshou 
Published: February 2007

AbstractContinuous locked suture technique in arterial anastomosis was used in a rat heterotopic small bowel transplantation model. Blood loss, time consumption and success rate of the technique, as well as long‐term blood flow and histological changes of arterial anastomosis and intestinal graft were compared with the traditional simple continuous suture technique. The results showed that the time consumption was similar between the two techniques while the continuous locked suture technique had a higher success rate (P = 0.016) and was more secure than the simple continuous suture technique. Moreover, it provided a higher long‐term blood flow. Under light microscopy and electron scanning microscopy, the anastomosis of continuous locked suture technique showed significantly less stenosis than those of simple continuous suture technique. No difference was found between the two techniques considering the graft intestinal histological changes. In conclusion, the continuous locked suture technique was a more superior technique than simple continuous suture technique in arterial end‐to‐side anastomosis considering long‐term hemodynamics. © 2007 Wiley‐Liss, Inc. Microsurgery, 2007.
Enthalpy relaxation in bisphenol‐A polycarbonate/poly(methyl methacrylate) blends
Authors: Penco Maurizio , Sartore Luciana , Sciucca Stefania Della 
Published: February 2007

AbstractBisphenol‐A polycarbonate (PC)/poly(methyl methacrylate) (PMMA) blends (PC/PMMA) were prepared by melt mixing with and without a trans‐esterification catalyst (tetrabutylammoniun tetraphenylborate), which is able to promote inter‐exchange reactions between PC and PMMA. Evidences of the ester–ester exchange reaction taking place were pointed out via Fourier Transform Infra‐Red and size exclusion chromatography analyses. A series of enthalpy relaxation measurements were carried out for the pure polymers and for blends thereof. The data were analyzed on the basis of the Tool–Narayanaswamy–Moynihan/Kohlraush–Williams–Watts model. This model characterizes the structural relaxation in the glass transition region by means of four parameters: the apparent activation energy (Δh*), the nonlinearity (x), the nonexponentiality (β), and the pre‐exponential factor (τ0). The apparent activation energy can be determined from the cooling rate dependence of the fictive temperature (Tf) measured using DSC. Δh* values of homogeneous blend and of the starting polymers were determined in this way, while an estimation of x, β and τ0 was proposed. Comparisons were made between a single glass transition temperature PC/PMMA blend and homopolymers data. The experimental values of Δh* suggest that the degree of cooperativity decreases on going from the starting polymers to the blend. POLYM. ENG. SCI., 47:218–224, 2007. © 2007 Society of Plastics Engineers.
Linear polymers with sulfur in the main chain. IV. Synthesis of thermotropic liquid‐crystalline polythioesters based on 4,4′‐biphenyldithiol with excellent adhesive properties
Authors: Hirano Hiroshi , Kadota Joji , Agari Yasuyuki , Harada Toshihiko , Tanaka Mitsuaki , Hasegawa Kiichi 
Published: February 2007

AbstractA series of sulfur‐containing linear polythioesters were synthesized from 4,4′‐biphenyldithiol (BPT) and bifunctionally aliphatic acyl dichlorides (ACs) by means of polycondensation. Polycondensations of BPT with azelaoyl chloride or sebacoyl chloride chosen as a model reaction system were investigated in several solvents by solution polycondensation, to find an optimal solvent to achieve high molecular weight and quantitative yield. Thus, all the polythioesters from BPT and AC (methylene number of 3–10) were synthesized in chloroform and their structures were confirmed by 1H‐NMR and Fourier transform infrared spectrophotometer. They were also evaluated by thermogravimetry and differential scanning calorimeter (DSC). Almost all of the BPT, polythioesters exhibited two distinct exothermic and endothermic peaks on first cooling and second heating in their DSC curves, respectively. Polarized microscope (PLM) observation clarified that the higher transition temperatures were isotropic temperatures (Tis). The odd–even effect between Ti and the methylene number was observed in these BPT polythioesters. Furthermore, almost all of the polythioesters showed thermotropic liquid‐crystalline behavior, as evidenced by a PLM observation. To know the effect of introduction of sulfur on adhesive properties of the polythioester/copper junction, a single lap shear test was carried out in comparison with corresponding 4,4′‐biphenyldiol (BPH) polyesters derived from BPH and ACs. It was clarified that the BPT polythioesters have greatly higher adhesive strengths in comparison with the BPH polyesters. POLYM. ENG. SCI., 47:262–269, 2007. © 2007 Society of Plastics Engineers.