气象要素的时间分布对五代桑螟数量影响分析

应用积分回归方法,分析气象要素对5代桑螟Diaphania pyloalis Walker数量影响的结果显示,各气象要素的时间分布对5代桑螟数值效应的变化较大,有的时段为正效应,有的时段为负效应;影响效应最大为相对湿度,日平均温度次之,降水和日照项对湿度和温度起着修饰作用。8月上旬高温多湿、8月中旬高温干燥对5代桑螟发生量有明显促进作用;9月上旬多湿和适度低温、9月中旬干燥和适度高温有利于5代桑螟数量增加。多湿环境有利于桑螟卵的生存和孵化,干燥环境有利于桑螟幼虫和蛹的生存。用11年历史值进行验证,吻合效果达到极显著。通过2007年的预测值与大田实际调查值对比,误差在13.6%,证明模拟的数学模型能准确地反映5代桑螟自然种群数量动态。     

Phylogenetics and biogeography of eastern Asian-North American disjunct genus Pachysandra （Buxaceae） inferred from nucleotide sequences

Pachysandra is an eastern Asian-North American disjtunct genus with three species, two in eastern Asia （Pachysandra axillaris and Pachysandra terminalis） and one in eastern North America （Pachysandra procurnbens）. Although morphological and cytological studies suggest a close affinity of Pprocumbens with P axillaris, molecular data from nuclear and chloroplast DNA regions have provided conflicting signals. In this study, we tested previous phylogenetic hypotheses using sequences of nuclear ribosomal DNA internal transcribed spacers and chloroplast ndhF gene from multiple individuals of each of the three species. We also estimated the time of divergence between eastem Asia and eastern North America. Our results support the morphological and cytological conclusion that P procumbens is more closely related to P axillaris than to P terminalis. The estimated time of divergence of P axillaris and P procumbens was 14.6±5.5 mya, consistent with estimates from many other eastern Asian-North American disjunct genera. The migration of Pachysandra populations from eastern Asia to North America might have occurred by way of the North Atlantic land bridge.     

Oral health and oral implant status in edentulous patients with implant‐supported dental prostheses who are receiving long‐term nursing care

Aim: The aim of this study was to investigate oral health and oral implant status in a group of edentulous patients receiving long‐term residential or nursing care (LTC), all of whom had implant‐supported fixed or removable dental prostheses. Material and methods: A dental examination was performed on a total of 3310 patients receiving LTC and from this population 35 edentulous patients in whom dental implants had been placed formed the cohort for this study. All examinations were performed by a specialist in hospital dentistry and took place in the patients’ own home environment. Oral health was assessed by means of a protocol which evaluated oral hygiene status, possible oral mucosal inflammation and oral mucosal friction levels. Any problems with the implant‐supported prosthesis, implant mobility or other complications were also assessed. In addition, patients were asked about any oral symptoms and their usual oral hygiene procedures. Results: About half of the subjects (17/35) were registered as having no/mild inflammation with 18 of 35 having moderate/severe inflammation. Twelve of the 35 patients had good/acceptable oral hygiene and 23 of 35 had poor/bad oral hygiene. Twenty‐one of the 35 patients depended on help from the nursing personnel for their daily oral hygiene procedures. Obvious problems with food impaction were noted in 11 patients. A total of 229 implants had been placed in 43 jaws supporting 40 full arch‐fixed prostheses and three implant‐borne overdentures. There was no evidence of mobility or fractures of either the implants or the prostheses. Fifteen implants showed some exposed screw threads. Pus was exuding from one implant site and general peri‐implant gingival hyperplasia was noted in two patients. Twenty‐four patients were completely satisfied with the function and appearance of their implant‐supported prostheses. Two patients were totally dissatisfied. Conclusion: This study indicates that oral implant therapy can be considered as a treatment of choice in elderly patients, even if oral hygiene is sub‐optimal.     

Biogas generation apple pulp

In view of the pressing problem that appears in our region (Asturias, north of Spain) with the residues from the cider production, it was decided to test this kind of material as a co-substrate joint with slaughterhouse waste in a laboratory unit.     

Circular permutation of ligand‐binding module improves dynamic range of genetically encoded FRET‐based nanosensor

Quantitative measurement of small molecules with high spatiotemporal resolution provides a solid basis for correct understanding and accurate modeling of metabolic regulation. A promising approach toward this goal is the FLIP (fluorescent indicator protein) nanosensor based on bacterial periplasmic binding proteins (PBPs) and fluorescence resonance energy transfer (FRET) between the yellow and cyan variants of green fluorescent protein (GFP). Each FLIP has a PBP module that specifically binds its ligand to induce a conformation change, leading to a change in FRET between the two GFP variant modules attached to the N‐ and C‐termini of the PBP. The larger is the dynamic range the more reliable is the measurement. Thus, we attempted to expand the dynamic range of FLIP by introducing a circular permutation with a hinge loop deletion to the PBP module. All the six circularly permutated PBPs tested, including structurally distinct Type I and Type II PBPs, showed larger dynamic ranges than their respective native forms when used for FLIP. Notably, the circular permutation made three PBPs, which totally failed to show FRET change when used as their native forms, fully capable of functioning as a ligand binding module of FLIP. These FLIPs were successfully used for the determination of amino acid concentration in complex solutions as well as real‐time measurement of amino acid influx in living yeast cells. Thus, the circular permutation strategy would not only improve the performance of each nanosensor but also expand the repertoire of metabolites that can be measured by the FLIP nanosensor technology.     

Divergent trends in anadromous salmonid populations in Norwegian and Scottish rivers

The Atlantic salmon (Salmo salar) is a charismatic anadromous fish of high conservation and economic value. Concerns have been expressed regarding the long-term viability of fisheries throughout the species''s distributional range because of abundance variations that cannot currently be explained or predicted. Here, we analyse long-term catch data obtained over a wide geographical range and across a range of spatial subscales to understand more fully the factors that drive population abundance. We use rod catch data from 84 Norwegian rivers over 125 years (1876–2000) and 48 Scottish rivers over 51 years (1952–2002). The temporal correlation in catches is very long-term, with trends persisting over several decades. The spatial correlation is relatively short-range, indicating strong local-scale effects on catch. Furthermore, Scottish salmon populations exhibit recent negative trends in contrast to some more positive trends in Norway—especially in the north.     

Trade-offs between activity and thermoregulation in a small carnivore,the least weasel Mustela nivalis

We studied factors influencing daily energy expenditures (DEE) of male least weasels (Mustela nivalis) using the doubly labelled water technique. The relationship between ambient temperature and DEE formed a triangular pattern, characterized by invariance of the maximum DEE and an inverse relationship between minimum DEE and temperature. A simple energetic model relating the DEE of male weasels to activity time (AT) and ambient temperature predicted that, across seasons, less than 10 per cent of measurements approach the upper bound of observed DEE. Male weasels were able to maintain a relatively constant maximum energy output across varying temperatures by adjusting their AT to changes in temperature. They achieved maximum energy expenditures in winter due to high thermoregulatory costs, and in spring and summer due to high levels of physical activity. This pattern exemplifies a ‘metabolic niche’ of a small mammal having extremely high energy expenditures primarily driven by ambient temperature.     

基于模型数据融合的长白山阔叶红松林碳循环模拟

 充分、有效地利用各种陆地生态系统碳观测数据改善陆地生态系统模型, 是当前我国陆地生态系统碳循环研究领域亟待解决的重要问题之一。该研究以2003~2005年长白山阔叶红松林的6组生物计量观测数据和涡度相关技术测定的碳通量数据为基础, 利用马尔可夫链-蒙特卡罗方法对陆地生态系统模型的关键参数(即碳滞留时间)进行了反演, 进而预测了长白山阔叶红松林生态系统碳库、碳通量及其不确定性。反演结果表明, 长白山阔叶红松林叶凋落物和微生物碳的平均滞留时间最短, 为2~6个月; 其次是叶和细根生物量碳, 二者的平均滞留时间为1~2 a; 慢性土壤有机碳的平均滞留时间为8~16 a; 碳在木质生物量和惰性土壤有机质库中的滞留时间最长, 平均滞留时间分别为77~109 a和409~1 879 a。模拟结果显示, 碳库和累积碳通量模拟值的不确定性将随着模拟时间的延长而增大。当气温升高10%和20%时, 长白山阔叶红松林总初级生产力年总量将分别增加6.5%和9.9%, 净生态系统生产力(NEP)年总量的变化取决于土壤温度的变化。若土壤温度保持不变, NEP年总量将分别增加11.4%~21.9%和17.6%~33.1%; 若土壤温度也相应升高10%和20%, NEP年总量的增幅反而下降甚至低于原来的水平。假设气候和植被保持在2003~2005年的状态, 2020年长白山阔叶红松林NEP年总量为(163±12) g C·m^–2·a^–1, 土壤呼吸年总量为(721±14) g C·m^–2·a^–1。马尔可夫链-蒙特卡罗方法是反演模型参数、优化模拟结果和评估模拟结果不确定性的有效方法, 但今后仍需在惰性土壤碳滞留时间的估计、驱动数据和模型结构的不确定性分析、模型数据融合方法方面进行深入研究, 以进一步提高碳循环模拟的准确性。     

小桐子花的性别与开花时间的相互关系

通过对小桐子(Jatropha curcas L.)花序上小花的开花顺序和小花性别的观察,发现其聚伞花序中心花的性别与其开花时间相关联,同时还和周围其它小花的性别有很大的相关性.中心花若在整个花序开花的第一天开放,仅有23.2%的可能是雌花;若在第二天及以后开放,有85%以上的可能为雌花.而中心花的性别又与其它花的性别相关,中心花如为雌花,那么聚伞花序上的其它小花有80%的可能性为雌花;但中心花若为雄花,那么整个聚伞花序上将不会再有雌花.研究小桐子的开花行为及性别控制规律,对于进一步人工调控小桐子花的性别表达,提高小桐子的产量、培育高产稳产品种,具有重要的应用价值.