Immunosuppression by Mutated Calreticulin Released from Malignant Cells

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Temporal-spatial distribution,environmental significance and release risks of phosphorus in the sediments of a tropical mountain’s deep drinking water reservoir in southeastern China

In this study, the fractionation and distribution of phosphorus (P) in the core sediments of the Shanmei reservoir were investigated by using the chemical extraction method in directions for the first time in order to understand its bio-availability, adsorption characteristics, potential release and environmental significance. The results of the study showed that P in the sediments mainly consisted of inorganic phosphorus (IP) and that IP mainly consisted of non-apatite phosphorus (NAIP). The horizontal and temporal distributions of the P fractions were different from each other, but the vertical distribution was similar, which indicated a trend of stabilization after falling. The content of total phosphorus (TP), IP, organic phosphorus (OP), NAIP, apatite phosphorus (AP), and bio-available phosphorus (BAP) in the sediments during the three seasons ranged from 193.85 to 1664.05 mg·kg^?1, 126.90 to 1127.70 mg·kg^?1, 43.74 to 669.29 mg·kg^?1, 57.62 to 937.07 mg·kg^?1, 32.58 to 250.71 mg·kg^?1, and 41.06 to 871.82 mg·kg^?1, respectively. NAIP contents in the sediments accounted for more than 50% of TP. Using an analysis from three aspects, the eutrophication risk index (ERI) could be used to assess the potential release of P in the sediments, and there was a high release risk of P in the sediments in the Shanmei reservoir.     

烟气脱硫石膏对滨海农耕土壤磷素形态组成的影响

为探明不同烟气脱硫石膏施用量对滨海农耕土壤中的全磷、有效磷、无机磷组分等的影响,通过田间试验的方式,分别在试验区土壤中施加0t/hm~2、15t/hm~2、30t/hm~2、45t/hm~2烟气脱硫石膏。研究结果表明:与对照组相比,各处理组的土壤全磷含量无显著差异,而土壤中的有效磷和渗滤液中的可溶性磷含量则随着烟气脱硫石膏施入量的增加而降低;施入烟气脱硫石膏后农耕土壤中无机磷含量显著增加,其中又以磷酸钙盐含量的增加为主,磷酸钙盐中的Ca2-P、Ca_8-P和Ca_10-P含量分别增加了30.8%—68.9%、35.2%—66.3%和7.3%—17.8%。烟气脱硫石膏的施用促进了植物的生长发育,有效磷的降低和无机磷组分中磷酸钙盐的增加并未影响到植物对磷素的吸收。因此,烟气脱硫石膏能有效地固定滨海农耕土壤中的溶解态磷,控制土壤过量磷素向水体迁移,降低附近水体富营养化发生的机率,保障区域水体生态系统环境安全。     

黄土高原不同土壤质地农田土壤碳、氮、磷及团聚体分布特征

结合野外观测和室内分析,研究了黄土高原不同土壤质地农田土壤碳、氮、磷含量及其生态计量学特征,以及土壤团聚体分布状况,以揭示土壤质地对区域农田土壤肥力的影响,以及土壤团聚体对肥力的调控作用.结果表明: 黄土高原农田土壤大团聚体含量、主要养分含量及其生态计量比值均随土壤质地由细变粗(壤质黏土→黏壤土→砂质壤土)逐渐降低;土壤pH值和微团聚体含量则呈现出相反的变化趋势. 随土壤黏粒含量增加,大团聚体含量、有机碳、全氮和全磷含量,以及C/P和N/P显著增加,土壤pH和微团聚体含量显著降低. 土壤有机碳、全氮和全磷含量,以及C/P和N/P随大团聚体含量的增加显著增加.表明区域尺度上农田土壤肥力状况取决于土壤质地,并受土壤大团聚体的调节.     

Association of red coloration with senescence of sugar maple leaves in autumn

We evaluated the association of red coloration with senescence in sugar maple (Acer saccharum Marsh.) leaves by assessing differences in leaf retention strength and the progression of the abscission layer through the vascular bundle of green, yellow, and red leaves of 14 mature open-grown trees in October 2002. Computer image analysis confirmed visual categorization of leaves as predominantly green, yellow or red, and chemical quantification of leaf pigment concentrations verified that leaf color reflected underlying differences in leaf biochemistry. Significantly lower chlorophyll concentrations within red and yellow leaves indicated that senescence was more advanced in leaves from these color categories relative to green leaves. Among leaf types, only red leaves contained high concentrations of anthocyanins. There were significant differences in leaf retention capacity among color categories, with the petioles of green leaves being the most firmly attached to twigs, followed by red and then yellow leaves. Microscopic analysis indicated that yellow leaves had the most advanced extension of the abscission layer through the vasculature, with green and red leaves having significantly less abscission layer progression than yellow. A more limited progression of the abscission layer through vascular bundles may be evidence of delayed leaf senescence that could extend resorption of mobile leaf constituents. Together, results from this study suggest an association between leaf anthocyanin content and functional delays in senescence.     

Go with the flow: tidal import and export of larvae from semi-enclosed bays

There is a growing body of evidence that suggests the effective functioning of marine reserves is dependent on the dispersal and recruitment of larvae. Enhanced production inside reserves is predicted to lead to a net larval export and increased settlement and recruitment outside reserve boundaries. However, larval retention in bays is also well documented. Since bays are increasingly being used as reserve areas, planktonic larvae of benthic marine invertebrates were sampled from two semi-enclosed marine reserves during flood and ebb tides to determine whether these bays are acting as net exporters of larvae. Neither reserve was a net importer or exporter of species richness, larval abundance or diversity, although one reserve showed a small export of species richness during the hours of darkness. Both reserves balanced the net import of some species with a net export of others, which was generally related to adult or larval abundance, although exceptions were found in one reserve. Significant effects of light were found, with the net import or export of some species occurring exclusively during either the hours of daylight or darkness. An increased understanding of larval sink-source dynamics in bays is essential for ensuring their effective use as marine reserves to meet specific conservation needs. Guest editors: J. Davenport, G. Burnell, T. Cross, M. Emmerson, R. McAllen, R. Ramsay & E. Rogan Challenges to Marine Ecosystems     

Narrow-leaved lupine seeds as a dietary protein source for fattening rabbits: a comparison with white lupine seeds

Lupine seeds have the potential to be an alternative to imported dietary proteins. In rabbits, it has been indicated that White lupine seed (WLS) is a suitable protein source. Other lupine species, for example, narrow-leaved lupine seed (NLS), have not yet been tested in rabbit diets. Two experiments were carried out to evaluate the effect of the dietary inclusion of NLS on growth performance, sanitary risk index (SRI), coefficients of total tract apparent digestibility (CTTAD) and nitrogen output in fattening rabbits. Narrow-leaved lupine was compared with WLS as a main protein source. For Experiment I, a total of 198 Hyplus rabbits (37 days of age) were allocated into two groups (99 rabbits per group), fed the WLS I diet (120 g/kg of WLS cv. Amiga) or the NLS I diet (150 g/kg of NLS cv. Probor), and used for performance and carcass trait evaluations. In addition, the CTTAD of the diets and the nitrogen output were determined in 10 Hyplus rabbits per treatment (37 days of age). For Experiment II, a total of 180 Hyplus rabbits (32 days of age) were allocated into two groups (90 rabbits per group), fed the WLS II diet (120 g/kg of WLS cv. Amiga) or the NLS II diet (130 g/kg of NLS cv. Primadona), and used for performance and carcass trait evaluations. In addition, the CTTAD of the diets was determined in 10 Hyplus rabbits per treatment (32 days of age). Regardless of the treatment, the dietary inclusion of NLS had a negative effect on growth of the rabbits. The nitrogen excretion and coefficients of nitrogen retention of rabbits were not affected by the treatments. In Experiment I, SRI (37 to 80 days of age) was higher in rabbits fed the NLS I diet than in those fed the WLS I diet (38.4% v. 23.2%, respectively; P = 0.031). Similarly, in Experiment II (32 to 74 days of age), SRI was higher in rabbits fed the NLS II diet than in rabbits fed the WLS II diet (37.8% v. 23.3%, respectively; P = 0.052). In conclusion, regardless of the variety, the dietary inclusion of NLS had no negative effect on the nitrogen output or dressing-out percentage of rabbits when compared to those of rabbits fed the WLS diets. With respect to the SRI and performance, however, NLS did not provide a satisfactory outcome.