平衡之生与失衡之亡——海丝特和卡瑟琳之三重人格比较

《红字》中的海丝特和《呼啸山庄》中的卡瑟琳是英美文学史上极富感染力的人物形象。虽然两人同样经历了坎坷崎岖的爱情道路,结局却迥然不同。弗洛伊德三重人格结构清晰地投射在两位女主人公的内心世界中,分别体现在追求爱情、矢志不渝的“本我”、遵循现实、历经磨难的“自我”和约定俗成、不可逾越的“超我”这三个层面上。当“本我”和“超我”的矛盾冲突加剧时,通过各种途径升华“自我”可以有效地缓和矛盾;与此同时,合理平衡矛盾冲突才能获得新生,而失去平衡的混乱只有在死亡来临才可消除。     

Biodegradation of chlorothalonil in soil after suppression of degradation

the degradation rate of chlorothalonil (2,4,5,6-tetrachloroisophthalonitrile) was significantly decreased after repeated application in field experiments. However, the degradation rate completely recovered after further application of chlorothalonil. Chlorothalonil was also degraded in a laboratory study, forming a stoichiometric amount of chloride anion. 4-Hydroxy-2,5,6-trichloroisophthalonitrile (TPN-OH) was also detected as a metabolite in the study. Bacterial which degrade chlorothalonil rapidly were isolated from the soil. The cell suspension of the bacteria transformed chlorothalonil to TPN-OH and chloride anion, but did not utilize chlorothalonil (=cometabolism). It seems that microbial acclimation has occurred during repeated application because the bacteria could not be detected in soil which was not treated with chlorothalonil.Dedicated to Professor J. C. G. Ottow on the occasion of his 60th birthday     

Repeated sequence RSα is diagnostic for Bradyhizobium japonicum and Bradyrhizobium elkanii

The genome of Bradyrhizobium japonicum and B. elkanii contains multiple copies of the repeated DNA sequence RSα. A collection of 18 B. japonicum, 4 B. elkanii and 72 other bacterial strains was screened by polymerase chain reaction (PCR) using a pair of primers specific for RSα. Only strains of B. japonicum and B. elkanii gave the predicted amplification product. Restriction analysis of PCR products obtained from different strains of B. japonicum showed that the RSα sequence was generally conserved. The usefulness of RSα as a specific probe for Bradyrhizobium strains capable of nodulating soybean was also demonstrated. Received: 11 May 1995     

Analysis of correlated discrete observations: background,examples and solutions

The goal of this paper is to highlight the use and interpretation of statistical techniques that account for correlation in epidemiological data. A conceptual statistical background is provided, and the main types of regression models for correlated data are highlighted. These models include marginal models, random effect models and transitional regression models. For each model type an example with data from the veterinary literature is provided. The examples are specifically used to highlight estimation procedures for parameters, and the interpretation of the estimated parameters. This paper emphasizes that statistical techniques and software to fit them are more widely available now, but that parameters have different interpretations in different model types. Consequently, we stress the importance of focusing on choosing the most appropriate model for the specific purpose of the analysis.     

减压升华脱除绿茶中的咖啡碱

以蒸青绿茶、炒青绿茶为材料,采用减压升华脱除法降低绿茶中的咖啡碱含量。考察了温度、压力、时间条件,以及茶叶种类、含水率和粒度等因素,对咖啡碱减压升华脱除的影响。结果表明,在70℃、-0·02~-0·08MPa条件下,处理14h左右,可使含水率为20%的蒸青绿茶的咖啡碱脱除率达到37%,并基本保持绿茶叶感官品质不变。条形蒸青绿茶在含水率20%的条件下,咖啡碱减压脱除的效果较好。在升华脱除过程中,较高的茶叶水分含量对咖啡碱脱除具有促进作用。减压升华脱除绿茶中咖啡碱的技术条件和设备要求较低,可有效降低传统绿茶中的咖啡碱。     

上农玉芹的选育及其特性

上农玉芹是上海农学院利用有性杂交法培育成功的芹菜新品种。经多年种植表明,该品种结合了父本美国实心芹和母本上海黄心芹的许多优点,小区试验的产量比母本黄心芹高出 30％以上（“玉芹”为每公顷5.25万公斤左右,“黄心芹”为3.67万公斤左右）,香味介于父、母本之间。该品种抗虫性、耐热和耐冻等特性都超过双亲或单亲之一。南至海南岛,北至江苏徐州等地均可种植。由于该品种高产、优质,且易栽培,因此自选育成功至1995年,种植面积已达2000公顷,占上海芹菜种植面积的70％。     

反复干旱法在甘蔗抗旱性研究中的应用

选取2个甘蔗品种4种下种方式在反复干旱区和非干旱区进行试验。研究结果表明:非干旱区以双芽种较好,而在反复干旱区经反复干旱法处理后种茎仍有较高的根系活跃吸收面积,萌芽率和出苗率都高,叶片气体交换特性较强的品种或处理,在大田试验中表现出较强的耐旱性,在干旱条件下栽培仍能达到较高的蔗茎产量和糖产量。4种下种方式中以剥叶不砍种处理综合表现最好,桂糖11号耐旱力比新台糖16号强。     

小麦苗期抗旱类型研究

为探索小麦苗期对水分胁迫的适应性,利用反复干旱法研究了942份小麦材料的苗期抗旱类型。结果表明,小麦苗期抗旱性存在显著差异,3次反复干旱后,小麦品种间成活率变异系数为4.6%～43.51%。根据品种反复干旱后成活率,供试品种对水分胁迫响应划分为抗旱型、耐旱型和敏感型。苗期抗旱性强的小麦品种具有较少种子根、较多次生根和较强分蘖量。小麦苗期抗旱性与后期抗旱性缺乏一致性,与品种的千粒重和冬春性无明显关系。     

单因素随机区组试验中重复测量数据分析及其SAS实现方法

结合两个实例,讨论了单因素随机区组试验中重复测量数据的分析方法,并用SAS程序进行了统计计算。对于不同地点的重复测量数据,在其变异来源中增加了一个地点取样误差,其SAS程序中,采用了Proc Anova语句,巧妙地在Model语句后加入了Test语句。对于不同时间点的重复测量数据,可以将单因素随机区组设计转化为裂区设计,单因素为主区因素,时间因素为副区因素,其SAS程序中,采用了Proc Mixed语句,并进行了同质性检验。     

Critical state parameters from intact samples of two agricultural topsoils

The critical state parameters of intact samples of a sandy loam (Eutric Cambisol) and a clay loam (Gleysol) were estimated in a constant cell volume triaxial apparatus. Samples were taken under wet and dry conditions. The parameters describing the clay loam were the more variable. This was true of both its initial condition and its response to deformation. Under dry conditions, the sandy loam was less sensitive to increasing stress but compacted more at low stress than the clay loam. Isotropic stress compacted the wet soils until the percentage saturation reached about 85–95% and axial loading caused little further compaction. The difference in strength between soils was greater for the wet samples, whereas the corresponding compactibility differences were greater under dry conditions. The sandy loam was stiffer than the clay loam and the shear modulus decreased exponentially with increasing specific volume before deformation. The rebound slope was about one-twentieth of the compression index for the dry soils and about one-third of the compression index for the wet soils. A simple model of recompression accounted for plastic deformation below the virgin compression line, where the critical state model usually assumes elasticity. The proposed model reproduced the main observed features of repeated isotropic loading.