Seafood mislabelling: comparisons of two western European case studies assist in defining influencing factors,mechanisms and motives

The global seafood industry, influenced by consumer demand, is closely linked to the global fishing industry, which determines the variety of fish available for consumption. The recently revealed issue of seafood mislabelling threatens to weaken this link by removing consumer power to influence patterns of fisheries exploitation through informed choice. Recognizing this, there is an urgent need to go beyond the mere documentation of the phenomenon and learn more about the origins of this problem and the nature of factors influencing its occurrence to develop solutions. In an attempt to understand seafood mislabelling more thoroughly in Europe, 226 cod products were purchased from Ireland and the UK, genetically identified using a DNA barcoding technique (COI barcoding gene), and species identification results were compared against product labels. Cod mislabelling proved more severe in Ireland than in the UK (28.4% vs. 7.4%). Moreover, whereas data show that in Ireland, cheaper species are sold as cod, in the UK, threatened Atlantic cod (Gadus morhua) may be sold as ‘sustainably sourced’ Pacific cod. Considering these countries operate under the same EU policies for seafood traceability and labelling, it is likely that this situation has been influenced by heightened consumer awareness in the UK, which has created an environment where mislabelling is discouraged. In addition to identifying samples, traceability information from packaged cod was used to trace products back to supplying companies. Although inconclusive in determining blame, this exercise has demonstrated that using traceability information can add explanatory power when attempting to determine responsibility for the occurrence of mislabelling.     

混养海湾扇贝对刺参池塘养殖环境的影响

为建立参贝混养的生态养殖模式,研究了海湾扇贝在池塘中与刺参混养,对养殖环境的影响。通过参贝混养与海参单养池的比较研究表明:参贝混养池的水质指标:氨态氮、亚硝酸盐等明显低于海参单养池;扇贝的滤食作用改善了水的透明度,参贝混养池明显高于海参单养池。参贝混养池中浮游生物的种类和数量优于单养池,海参喜食的底栖硅藻的生物量较多;浮游动物的种类较少,规格也较小。为池塘参贝生态养殖提供了参考依据。     

Development of transparent bacterial cellulose nanocomposite film as substrate for flexible organic light emitting diode (OLED) display

Nanocomposite film composed of bacterial cellulose (10-50 wt.%) and poly-urethane (PU) based resin was fabricated and utilized as a substrate for flexible organic light emitting diode (OLED) display. The performance of the nanocomposite satisfied the criteria for the substrate of OLED with an additional feature of flexibility. The visible light transmittance of the nanocomposite film was as high as 80%. Its thermal stability was stable up to 150 °C while its dimensional stability in terms of coefficient of thermal expansion (CTE) was less than 20 ppm/K. After OLED was fabricated on the substrate through thermal evaporation technique, the OLED performed highest current efficiency of 0.085 cd/A and power efficiency of 0.021 lm/W at 200 cd/m² while retained its flexible feature, suggesting that bacterial cellulose nanocomposite is a promising material for the development of substrate for flexible OLED display.     

洱海水体光学特性的季节变化及其影响因素分析

为了探究人类活动对洱海水体富营养化进程的影响,2014年4月、7月、11月和2015年1月在洱海全湖设置36个采样点进行采样监测,研究洱海光学衰减系数(K)、透明度(SD)、浊度(Turb)和叶绿素a(Chl-a)的季节变化规律及其相关性,并分析沉水植物分布对光学特性的影响,以期为洱海富营养化治理和控制提供基本数据支持。结果表明,光学衰减系数的季节变化规律为春季(0.59 m-1)冬季(0.68 m-1)秋季(0.95 m-1)夏季(1.05 m-1);叶绿素a含量与光学衰减系数的季节变化规律相同,为春季(5.24μg/L)冬季(5.49μg/L)秋季(12.33μg/L)夏季(14.22μg/L);透明度季节变化规律为夏季(1.86 m)秋季(2.28 m)春季(3.00 m)冬季(3.07 m);浊度季节变化规律是春季(32.50 mg/L)冬季(32.52 mg/L)秋季(32.64 mg/L)夏季(32.70 mg/L)。光学衰减系数与透明度、浊度和叶绿素a均呈显著正相关(P0.01),相关系数分别为0.648、0.523和0.467;透明度与叶绿素a和浊度均呈显著负相关(P0.01),相关系数分别为0.497和0.564;浊度与叶绿素a显著正相关(P0.01),相关系数为0.241。叶绿素a在一定程度上会影响光学衰减系数,但不是其主要影响因素。在秋季和冬季,沉水植物区的水体光学衰减系数显著低于无沉水植物区(P0.05),但这种差异在春季和夏季不显著(P0.05)。在一年中的各季节,沉水植物区与无沉水植物区的水体透明度和叶绿素a含量均无显著差异(P0.05);沉水植物区的水体浊度显著低于无沉水植物区(P0.01)。     

评价大米储藏品质的炊饭特性指标的研究

提出了评价大米储藏品质的炊饭特性新指标——光透过率差。实验证明，随着大米品质的劣化，光透过率差明显变小。以此指标为主，结合原有的加热吸水率和ｐＨ值，对因生霉和陈化引起的大米储藏品质的变化，都能较好地进行评价。同时对影响这些指标稳定的实验因素也进行了探讨。     

保蚕宁2号防治柞蚕空胴病的研究

室内药敏试验０．１％—０．５％保蚕宁２号对柞蚕链球菌有抑制作用，四龄盛食期添食０．１３％保蚕宁２号对柞蚕再感染空胴病有防治作用，旦效果显著。小区试验经添食药物的空胴病发病率下降６９．５％，死笼茧率平均下降３８．２５％，结茧率平均提高５０．２５％。农村多点试验治愈率达６３％，发病率下降６７．３％，结茧率提高５２．１１％。保蚕宁２号药源充足，价格适宜，可在柞蚕生产区普遍推广应用。     

应用高光谱数据定量反演查干湖水质参数研究

湖泊水质下降和富营养化问题日益严重,传统监测方法已经日益不能满足水质监测的需要。该文通过野外高光谱仪器测定查干湖水体反射光谱,分析研究水体反射光谱特征与水质参数叶绿素a含量、透明度和浊度之间的关系,运用多种半经验算法建立反演模型。结果表明:单波段光谱反射率与叶绿素a和浊度的相关系数较小,但与透明度相关系数较高;光谱反射率通过对数、比值转换,可以有效的提高叶绿素a和浊度估测模型的精度,却对透明度作用不大。总体来说,叶绿素a和浊度估测模型效果较好,透明度高光谱估测模型相对较差,需进一步研究。     

苹果汁澄清方法的研究

采用自然澄清法、硅藻土澄清法、明胶澄清法和果胶酶澄清法4种不同的澄清方法对澄清苹果汁加工工艺进行了比较研究，发现果胶酶能够有效地澄清苹果汁。分别考察了pH值、果胶酶添加量、温度、放置时间等因素对果胶酶澄清效果的影响，得出果胶酶澄清的最佳实验条件为pH4．0、0．4％果胶酶加入量、温度45℃、静置4ha     

看水越冬及其生物学分析

根据黑龙江、吉林地区数十个鱼类越冬池的实测数据 ,从水色、透明度、浮游生物与水体溶氧间的相互关系 ,总结如下规律 :1 水体透明度与浮游植物量负相关 ,与浮游动物量正相关。透明度 <5 0cm者 ,浮游植物丰富而极少浮游动物 ,一般氧气充足 ;透明度 >80cm者 ,多滤食性浮游动物 ,浮游植物少 ,一般溶氧量较低。越冬池透明度以 5 0～ 70cm为宜。 2 根据水体透明度可了解越冬池营养盐的丰欠 ,在越冬中、后期“肥水 (浮游植物多 )易缺肥而瘦水 (浮游动物多 )不易缺肥”。 3 目测冰下水体中鱼类的活动状况和兼测水温变化 ,可为池鱼越冬效果预测提供重要依据