活性炭对蔗糖的吸附特性

活性炭吸附蔗糖是一种化学吸附过程，蔗糖是以单分子铺展的形式被吸附于活性炭表面，其吸附速率由内扩散所控制。

螺旋藻基因组结构分析和藻胆蛋白的适应性进化

螺旋藻 (Spirulina，或称节旋藻 Arthrospira) 是一类丝状不形成异型胞的蓝藻，常分布于湖泊、池塘和半咸水中。作为目前利用最广泛的经济微藻，螺旋藻的规模培养、生理生化以及分子遗传等都受到了广泛的关注。但由于缺乏足够的基因组信息，影响了螺旋藻的品种改良以及进一步的基因功能产品的开发。 本研究从挑取单藻丝开始，建立了钝顶螺旋藻 (Spirulina platensis) 的纯培养体系，并构建插入片段分别为1-2Kb和4-6Kb的基因组文库，利用鸟枪法进行全基因组测序，共得到具有8倍覆盖度的7.4Mb拼接后的基因组数据。在该草图中，预测有7795个开放读码框 (ORFs)，其中包括长度小于120个氨基酸的ORFs和非全长ORFs。在所有蛋白编码序列中，约有39%的基因是螺旋藻特有的，此外，还有389个基因相对于其他蓝藻，与非蓝藻基因有着更高的相似性。通过Pfam结构域聚类分析发现，螺旋藻含有特有的结构域，如Peptidase_MA、DMT、OB、ATP-grasp、Flavokinase 等。 由于目前尚未有成熟的螺旋藻遗传转化系统，而其体内复杂的限制性内切酶系可能是妨碍外源基因顺利导入和整合的关键因素。在此草图的基础上，我们利用比较基因组学和分子进化的手段，深入分析了螺旋藻及其他蓝藻的限制修饰系统 (Restriction-modification system)，为建立螺旋藻的遗传转化技术，并实现后续的螺旋藻基因功能验证模式奠定了基础。 螺旋藻及其他蓝藻的基因组计划提供了大量基因组序列和结构信息，有助于我们深入了解光合微生物基因的结构、功能和进化，以及环境因子或特定突变是如何塑造其基因组的。本文以藻胆蛋白为例，利用分子进化和群体遗传学理论，描绘出一幅藻胆蛋白进化的动态图景，并分析了环境 - 结构 - 功能之间的相互联系，为藻类捕光色素进化机制理论提供了科学依据。 本研究结果发现低光适应型原绿球藻和海洋聚球藻的藻红蛋白中正选择位点分布有着显著差异，提示二者的藻红蛋白基因有不同的进化模式；正选择作用位点多集中在藻胆蛋白的色基结合区域及XY发卡结构处，这些结构域主要与藻胆蛋白的光能捕获、能量传递和结构组装有关。该研究结果不仅揭示了正选择作用的重要性，而且提示光质、光强和能量传递压等可能是潜在的正选择压力。此外，又深入研究了高光和低光适应型两个生态群体的原绿球藻藻红蛋白基因系统发育、种内多态性和种间变异度，以此揭示环境因子对藻胆蛋白进化的影响。 本研究首次对螺旋藻全基因组进行测序，并以藻胆蛋白为例，从分子进化角度揭示其结构和功能的关系，并首次提出正选择压力可能是促使藻胆蛋白功能分化的主要原因，并认为原绿球藻中藻红蛋白的进化呈现出不同的模式，新的捕光色素的出现以及其所处的海洋环境可能使藻红蛋白获得了新的功能。

Safety of tetanus toxoid in pregnant women: A hospital-based case-control study of congenital anomalies

Reported are the results of the Latin American Collaborative Study of Congenital Malformations (ECLAMC), a hospital-based case-control study of 34 293 malformed and 34 477 matched nonmalformed newborn controls. No statistical differences were found between the malformed and control groups, exposed or not exposed to tetanus toroid.

黄铁矿热转变过程的岩石磁学研究

Pyrite is the most stable iron-sulfide in reduced environment, and plays an important role in geochemical iron-sulfur cycling of sediments. Thus, the presence of pyrite in sediments and rocks is an important indicator of sedimentary environments. Previous studies on the thermal products of pyrite showed that all of the products (e.g., pyrrhotite, magnetite, hematite) have strong capability of carrying remanence. To deepen our understanding of the environmental and paleomagnetic significances of pyrite, the mineral transformation processes of pyrite upon heating were systematically investigated in this study using intergrated rock magnetic experiments (in both argon and air atmospheres) and X-ray diffraction analysis. The room temperature susceptibility of the paramagnetic pyrite is about 2.68×10-5 SI. In argon atmosphere (reducing environment), pyrite was transformed into monoclinic stable single domain (SD) pyrrhotite above 440 C. The corresponding coercive force and remanence coercivity are about 20 mT and 30 mT, respectively. In contrast, in air atmosphere (oxidation environment), the intermediate thermal products of pyrite are magnetite and pyrrhotite, which were quickly further oxidated to SD hematite, which has coercivity of about 1400 mT. In addition, the hematite particles gradually grow from SD to PSD grain size region by multiple heating runs. The transformation processes of pyrite in oxidation atomosphere can be interpreted by three possible pathways: (1) pyrite→magnetite→hematite; (2) pyrite→pyrrhotite→magnetite→hematite; and (3) pyrite→pyrrhotite→hematite. Low-temperature magnetic experiments show no transitions for pyrite. Despite that low-temperature magnetic method is not suitable for identification of pyrite, it is clear in this study that the high-temperature thermomagnetic measurements (e.g.,  -T and J-T curves) are very sensitive to the presence of pyrite in sediments and rocks. Nevertheless, for the thermal treatment products, low-temperature magnetic measurements showed the 34 K transition of pyrrhotite and the 250 K Morine transition of hematite. Iron-sulfide has also been found on Martian meteorolites by other workers. Therefore, systematic study of rock magnetism of pyrite (and other iron-sulfides) and their products will have great significances for both paleomagnetism and planetary magnetism.

引起红土表层硅铝比值增大原因的可能性探讨

中国南方的红土风化壳，是强烈化学风化作用的产物，被认为是处于或经历了脱硅富铝化阶段。但是在红土剖面上部常常出现Si/Al或SiO2/R2O3比值不降反升的现象，给运用这一指标指示化学风化强度带来了困难。本文通过对贵州平坝、新蒲及花溪碳酸盐岩红色风化壳化学风化程度的研究，以及中国南方几种不同结晶母岩上发育的红土的化学风化强度指标的对比讨论，探讨了产生这种现象的可能性原因。

CÓLICA em equídeos sob pastejo em Panicum maximum na Região Amazônica.

Equipe multidisciplinar: Ademir Hugo Zimmer (CNPGC) José Diomedes Barbosa Neto (UFPA) Liana Jank (CNPGC) Paulo Vargas Peixoto (UFRRJ) Rodrigo Amorim Barbosa (CNPGC) Vanessa Felipe de Souza (CNPGC)

BRS 1055: híbrido simples de milho.

2009

BRS 1060: híbrido simples de milho.

2009

Manejo do solo no sistema de produção orgânico de hortaliças.

2008

Perdas de água, solo, nutrientes e matéria orgânica em área cultivada em cebola sob diferentes sistemas de manejo de solo.

2009

Diagnóstico dos principais problemas no cultivo de hortaliças no Estado do Amazonas.

2009

Cooperação técnica e produção familiar sustentável de hortaliças: análise dos condicionantes e determinantes para a formulação de uma política nacional de segurança alimentar e nutricional para o Haiti.

2009

Podridões fúngicas de colmo na cultura do milho.

2008