Feeding by short-snouted weevils on seedlings of seven tree species planted beneath Norway spruce at differing stand densities

1 Short-snouted weevils, including Strophosoma spp. and related species, may damage tree seedlings. We investigated the damage caused by these weevils feeding on seedlings of seven tree species planted in clear-cuts and under shelterwoods with three densities (control, dense, and sparse).
2 There were no pronounced differences in damage caused by short-snouted weevils in the various shelterwood densities. Most feeding occurred in the clear-cuts during the first year, whereas more seedlings were damaged in the shelterwoods of all densities in the second year. In the third year, virtually no feeding occurred in either the clear-cuts or shelterwoods. We cannot explain this pattern of damage, but a fallow period of 2 years seems to prevent short-snouted weevil damage.
3 We determined the general feeding preferences for short-snouted weevils to be cherry, lime > beech, oak, spruce > maple, ash. However, although Strophosoma mellanogrammum [Correction added after online publication 8 December 2008: Strophosoma melanogrammum corrected to Strophosoma mellanogrammum ] was observed feeding on seedlings, no full short-snouted weevil inventory was conducted, so caution must be exercised when drawing conclusions from this study regarding weevil damage patterns and feeding preferences.
4 Short-snouted weevils can sometimes occur in large numbers and may destroy entire reforestation projects, but in our study their influence on seedling growth and survival was minor.     

Meat odour and flavour and indoles concentration in ruminal fluid and adipose tissue of lambs fed green herbage or concentrates with or without tannins

A 2 × 2 factorial experiment was carried out to evaluate the effect of herbage or concentrate feeding system and tannin addition to diet on skatole and indole in ruminal fluid and adipose tissue and meat sensory properties. Twenty-eight male lambs aged 45 days were randomly assigned to one of two feeding systems (vetch green herbage or concentrates, n = 14) and within feeding system to one supplement (quebracho tannins added to the diet or none). Animals were kept in singular pens and slaughtered at the age of 105 days. Indole (P < 0.05) and skatole (P < 0.01) concentrations in ruminal fluid were higher in lambs fed herbage compared to those given concentrates. Skatole in ruminal fluid tended to be present at lower concentrations in animals that received the tannin supplementation (P = 0.07). Indole was also higher in the caudal fat of animals fed green vetch compared to those fed concentrate (P = 0.04). Skatole concentration was lower in the fat of lambs fed concentrates compared to those given herbage (P = 0.05) and was lower in the fat of animals supplemented with tannins compared to the animals not supplemented (P = 0.01). Sheep meat odour was lower in meat from animals supplemented with tannins compared to those not supplemented (P < 0.01). It is concluded that tannins are more effective in reducing skatole formation in ruminants when they are associated with concentrate diets than green herbages.     

How do plants “notice” attack by herbivorous arthropods?

Precise and deep comprehension of plant responses to herbivorous arthropods requires detailed knowledge of how a plant “notices” the attack. Herbivore attack is not restricted to plant wounding by feeding, but instead different phases of attack that elicit a plant response need to be distinguished: touch, oviposition and feeding. Touch, secretions released with eggs and regurgitate delivered during feeding may act in concert as elicitors of plant defence. Here, we discuss the current knowledge of what a plant “notices” during the different phases of herbivore attack and how it responds at the molecular, physiological and ecological level. Understanding the mechanisms of plant responses to the different phases of herbivore attack will be a key challenge in unravelling the complex communication pathways between plants and herbivores.     

BIODIVERSITY RESEARCH: Diversity and distribution of macroinvertebrates in lentic habitats in massively altered landscapes in south‐eastern Australia

Aim We investigated whether faunas of lentic macroinvertebrates differed among two landscape types: (1) those that are largely covered in forests (presumed to be in a more pre‐human‐impact condition) and (2) those that are completely cleared for agricultural exploitation (massively altered). Location Five pairs of landscapes (each pair referred to as a region) – one of each landscape type – across a 30,000 km² region of north‐central Victoria, Australia. Methods Each individual waterbody was surveyed three times (austral spring 2006, autumn 2007, and spring 2007) for invertebrates. Waterbodies were characterized by measurements of static (e.g. abutting vegetation cover) and labile (e.g. pH) variables. Data were analysed using hierarchical Bayesian models of species richness, α‐ and β‐diversities and functional feeding groups. Assemblage composition was related to landscape and in‐waterbody characteristics. Results Neither measured, nor asymptotic estimates of, species richness differed among landscape types, notwithstanding consistent differences in in‐waterbody habitat characteristics among waterbodies in the two landscape types. There were no discernible differences in patterns of α‐ and β‐diversities at landscape scales relating to landscape type. Habitat diversity of waterbodies at the landscape scale did not affect β‐diversity, although distinct waterbodies within landscapes tended to have more distinct faunas. Main conclusions The lentic macroinvertebrate faunas are relatively homogeneous over the entire region, with little differentiation between wooded and cleared landscapes. The regional fauna may be a homogenized subset of native species, possibly arising from the huge numerical predominance of lentic habitats in agricultural landscapes producing ‘spill‐over’ effects into forested landscapes. Of taxa more frequently found in one or other landscape type, trophic group diversity was greater in forested landscapes.     

用生物信息学方法寻找肝癌特异性表达基因转录调控模式

为了对肝癌(hepatocellularcarcinoma,HCC)的分子发病机理进行研究,首先对肝癌基因表达谱数据用t-检验算法进行了分析,找到了肝癌中特异性表达基因(characteristicgenes).然后把这些基因结合已知的肝HNF家族转录因子染色质免疫共沉淀结合DNA启动子芯片(ChIP-chip)实验数据用SAEM算法进行分析,得到了肝癌特异性表达基因的转录调控关系,并寻找到了多个HNF家族转录因子调控单基因的转录调控模式.结果表明HNF家族转录因子对大量具有重要功能的肝癌特异性表达基因进行了转录调控,并且多个HNF家族转录因子调控单基因可以形成前馈环和多输入调控等模式.     

5-HT2和5-HT3受体在外周初级感觉神经末梢痛反应和痛调制中的相互作用

目的：探讨5-HT2和5-HT3受体亚型在5-HT引起外周痛反应和痛调制中的相互作用及其机制;方法：在大鼠三又神经节神经元标本上应用全细胞膜片钳技术记录5-羟色胺激活电流（15_HT）,并结合痛行为实验进行观察。结果：在大多数受检细胞（54／88,61．4％）特别是中、小型细胞外加5-HT可引起一快去敏感的内向电流,此内向电流能被5-HT,受体特异性激动剂2-甲基-5-羟色胺所模拟,被5-HT3受体拮抗剂ICS250-930可逆性阻断,而5-HT2受体激动剂α-甲基-5-羟色胺则有明显增强15-HT的作用,5-HT1受体激动剂R-（＋）-UH301无明显反应。在进一步的整体清醒动物的行为学试验中我们观察到,大鼠后肢掌底皮下注射5-HT（10-5,10-4和10-3mol／L）引起浓度依赖性的痛行为反应,而用5-HT2和5-HT3受体特异性拮抗剂Cyproheptadine和ICS250-930分别阻断相应受体亚型后,5-HT引起的痛行为反应的强度序列为：5-HT〉5-HT＋ICS〉5-HT＋Cyp。结论：本文结果提示：5-HT所引起的痛反应中,在初级感觉神经元水平5-HT3受体可能仅起着启始作用,而5-HT,受体则在伤害性信息的维持和调制过程中发挥更大的作用。     

The Case of Paul Kammerer: Evolution and Experimentation in the Early 20th Century

To some, a misguided Lamarckian and a fraud, to others a martyr in the fight against Darwinism, the Viennese zoologist Paul Kammerer (1880–1926) remains one of the most controversial scientists of the early 20th century. Here his work is reconsidered in light of turn-of-the-century problems in evolutionary theory and experimental methodology, as seen from Kammerer’s perspective in Vienna. Kammerer emerges not as an opponent of Darwinism, but as one would-be modernizer of the 19th-century theory, which had included a role for the inheritance of acquired characteristics. Kammerer attempted a synthesis of Darwinism with genetics and the chromosome theory, while retaining the modifying effects of the environment as the main source of favorable variation, and he developed his program of experimentation to support it. Kammerer never had a regular university position, but worked at a private experimental laboratory, with sidelines as a teacher and a popular writer and lecturer. On the lecture circuit he held forth on the significance of his science for understanding and furthering cultural evolution and he satisfied his passion for the arts and performance. In his dual career as researcher and popularizer, he did not always follow academic convention. In the contentious and rapidly changing fields of heredity and evolution, some of his stances and practices, as well as his outsider status and part-Jewish background, aroused suspicion and set the stage for the scandal that ended his career and prompted his suicide.     

正交实验研究白刺种子尿囊素提取工艺

利用高效液相色谱法测定尿囊素的含量,本文采用正交实验,对白刺种子尿囊素的提取工艺进行了优化.结果表明各因素对尿囊素的提取效果的影响程度为乙醇浓度＞温度＞料液比＞提取时间＞提取次数.从而确定白刺种子中尿囊素的最佳提取工艺为乙醇浓度为60%,料液比为1∶12(W/V),提取温度为80℃,提取时间为1 h,重复提取3次.     

航天搭载与非搭载舟形藻(Navicula tenera)培养基的优化

通过单因子和正交实验探讨了培养液中不同浓度KNO3、Na2HPO4、FeC l3和Na2S iO3对通过“神舟5号”飞船搭载与非搭载舟形藻(Navicula tenera)生长的影响,确立了适合搭载与非搭载舟形藻生长的最佳培养基组合。结果表明,经搭载后舟形藻生长所需的营养盐组合发生了变化。通过正交实验筛选出适合搭载舟形藻生长的最佳培养基为含300 mg.L-1KNO3、60 mg.L-1Na2HPO4.12H2O、24 mg.L-1FeC l3和700 mg.L-1Na2S iO3.9H2O的F/2培养基;适合非搭载舟形藻生长的最佳培养基为含600 mg.L-1KNO3、60 mg.L-1Na2HPO4.12H2O、12mg.L-1FeC l3和700 mg.L-1Na2S iO3.9H2O的F/2培养基。     

Modeling and optimization of hairy root growth in fed‐batch process

This article proposes a feeding strategy based on a kinetic model to enhance hairy roots growth. A new approach for modeling hairy root growth is used, considering that there is no nutrient limitation thanks to an appropriate feeding, and the intracellular pools are supposed to be always saturated. Thus, the model describes the specific growth rate from extracellular concentration of the major nutrients and nutrient uptakes depend on biomass growth. An optimized feeding strategy was determined thanks to the model to maintain the major nutrient levels at their optimum assuming optimal initial concentrations. The optimal feed rate is computed in open loop using kinetic model prediction or in closed loop using conductivity measurements to estimate biomass growth. Datura innoxia was chosen as the model culture system. Shake flask cultures were used to calibrate the model. Finally, cultures in bioreactor were performed to validate the model and the control laws. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010