渔源乳酸菌降解养殖水体氨氮的效果研究

自野生和养殖鱼体内分离出4株乳酸菌,分别为魏斯氏乳酸菌、植物乳杆菌、粪肠球菌和乳酸乳球菌。在水温25℃、盐度35及pH 8.3下,研究了用其单一菌株及混合菌株的菌体培养液和离心菌体去除实验室海水鱼类养殖系统水体中氨氮的效果,以不添加乳酸菌的处理为对照组。结果表明,菌体培养液和离心菌体对水体氨氮的降解效果相同。添加乳酸菌的处理组氨氮水平在24h后均比对照组显著下降,之后维持相对平稳水平。其中,魏斯氏乳酸菌处理的菌体培养和离心菌体组1~5d氨氮分别为0.13~0.10mg/L和0.15~0.10mg/L,24h降解率分别为41.48%和37.20%;植物乳杆菌处理组1~5d氨氮分别为0.15~0.08mg/L和0.16~0.08mg/L,24h降解率达35.10%和32.50%;粪肠球菌在1~5d氨氮分别为0.16~0.08mg/L和0.15~0.07mg/L,24h降解率分别为23.90%和29.27%;乳酸乳球菌在1~5d氨氮分别为0.16~0.08mg/L和0.18~0.08mg/L,24h降解率分别为29.70%和23.90%。混合菌株对氨氮降解效率总体低于单一菌株。渔源乳酸菌对养殖水体氨氮有不同程度降解作用,但菌株配伍需要根据菌株自身特性及营养源互补性进行科学配比。

Ecological effects of co-culturing sea cucumber Apostichopus japonicus (Selenka) with scallop Chlamys farreri in earthen ponds

Monthly changes in sedimentation and sediment properties were studied for three different culture treatments： sea cucumber monoculture （Mc）, sea cucumber and scallop polyculture （Ps-c） and scallop monoculture （Ms）. Results indicated that the survival rate of sea cucumber was significantly higher in Ps-c cultures than in Mc cultures. Sea cucumber yield was 69.6% higher in Ps-c culture than in Mc culture. No significant differences in body weight and scallop shell length were found between Ps-c and Ms cultures. The mean sedimentation rate of total particulate matter （TPM） was 72.2 g/（m^2.d） in Ps-c cultures, with a maximum of 119.7 g/（mE.d）, which was markedly higher than that of Mc （mean value）. Sedimentation rates of organic matter （OM）, total organic carbon （TOC）, total nitrogen （TN） and total phosphorus （TP） in Ps-c cultures were also significantly higher than those in Mc cultures. TOC and TN contents of sediment increased rapidly in the first 5 months in Ms cultures and remained at a high level. TOC and TN contents in Mc and Ps-c cultures decreased during sea cucumber feeding seasons and increased during sea cucumber dormancy periods （summer and winter）. The study demonstrates that co-culture of sea cucumber and scallop in earthen ponds is an alternative way to alleviate nutrient loads and improve water quality in coastal aquaculture systems. Moreover, it provides the additional benefit of an increased sea cucumber yield.

真理、理智与冒犯情感

在齐克果的著作中,"冒犯"指称着个体在真理认识活动中出现的一种情感。按照《哲学片段》中的分析,理智在追求真理时陷入了一种严重的认识困境:理智感到了冒犯。这是一种在冒犯中与真理僵持较劲的认识论状态。在《致死的疾病》中,齐克果还从意志的角度分析了冒犯在困境中的不同表现。依据齐克果的相关文本,真理认识者的冒犯情感可归纳为三种表现方式:理智的自弃、理智的迟疑和理智的反抗。在齐克果看来,真理认识这个理性活动是冒犯这种情感所推动的。真理认识和理智冒犯之间的这种内在关系,充分展示了情感在真理认识中的重要作用。

界定“个人权利”:建构还是解构?——评香港浸会大学“个人与社群:对立或共融?”论坛

自由主义是当今世界的主导性思潮,其立论建立在个人权利基础上。面对这个立论,当如何处理个人和社群的关系?自由主义的回答十分明确:尊重个人权利,通过契约而协调社群秩序。其基本导向是:个人权利优先,社群利益辅之。在这个问题上,基督教和儒家都持有与自由主义不同的立场观点。

利玛窦《天主实义》中“为善”的生存张力

在《天主实义》第六篇中,中士和利玛窦(Matteo Ricci,1552—1610)围绕“为善”问题展开对话。由于生存意识的差异和误解,双方一直在概念争论上陷于泥沼。本文通过追踪“为善”问题的生存意识,将双方关于“利”与“仁义”、“有意”与“无意”的争论还原为一种关于生存悖论的生存出发点之争。本文指出,中士强调对善观念的解构,利玛窦坚持对生存出发点的建构。但由于双方都对辩证性的生存张力缺乏足够的体会,因此各自的生存主张难免顾此失彼。与此同时,本文通过对原始文本的分析,指出孟子的“仁义”和张载的“无意”都源于对生存悖论的深刻体会,他们在提供一种必要的解构力量的同时,也试图努力重构一种内在于人性本身的生存出发点。