Carrion flies of forensic interest: a study of seasonal community composition and succession in Lisbon,Portugal

Information on Diptera community, seasonality and successional patterns in every geographical region is fundamental for the use of flies as forensic indicators of time of death. In order to obtain these data from the Lisbon area (Portugal), experiments were conducted during the four seasons of the year, using piglet carcasses as animal models. Five stages were recognized during the decomposition process. The stages, besides visually defined, could be separated taking into account the occurrence and abundance of the specific groups of Diptera collected. In general, the bloated stage recorded higher abundance and species‐richness values. Seventy‐one species were identified, belonging to 39 families, in a total of 20 144 adult Diptera collected. Autumn yielded the highest values of species richness, whereas winter had the lowest. In all seasons of the year, Calliphoridae was the dominant family; Muscidae and Fanniidae were very abundant as well. Calliphora vicina Robineau‐Desvoidy, Calliphora vomitoria (Linnaeus), Chrysomya albiceps (Wiedemann), Lucilia ampullacea Villeneuve, Lucilia caesar (Linnaeus), Lucilia sericata (Meigen) (Calliphoridae), Hydrotaea ignava (Harris), Muscina prolapsa (Harris), Synthesiomyia nudiseta (van der Wulp) (Muscidae), Piophila megastigmata McAlpine, Stearibia nigriceps (Meigen) (Piophilidae) and Nemopoda nitidula (Fallén) (Sepsidae) were revealed to be very important members of the Diptera community collected. The necrophagous behaviour, demonstrated by their immatures, using carrion as a food source makes them useful forensic indicator species. Also of relevance is the presence of Chrysomya megacephala (Fabricius), S. nudiseta and P. megastigmata, foreign species established in the local carrion communities. This study also marks the first record of S. nudiseta in Portugal.     

Ultrastructural Studies of Spermiogenesis of Conocephalus saltator (Saussure)

The acrosome of the spermatozoa is the organelle involved in its penetration through the ova membranes during the fertilization process. Several features of this process are considered to be related to the fertilization events e.g. some substance coats outside the membrane. During the maturation process the spermatozoa of Conocephalus saltator develop a coat of tubules and filaments which overly some membrane regions in a specific array. The mature spermatozoa are seen to adhere in these regions and form threads of 20 cells long and five to six wide. It is suggested that the external coat plays a role in this 'sticking' phenomenon.     

胞外ATP对AlCl3诱导的细胞死亡过程中胞内H2O2和Ca2+水平的影响及其生理机制分析

该实验以烟草悬浮细胞 BY 2 为材料,在烟草悬浮细胞中分别加入0.05、0.10、0.15、0.20 mmol·L^-1AlCl₃,以等体积去离子水处理的悬浮细胞液为对照,并依据前述实验结果选择0.15 mmol·L^-1 AlCl₃,分别添加5 mmol·L^-1 DMTU(H₂O₂ 抑制剂)、20 μmol·L^-1CaCl₂、15 μmol·L^-1 LaCl₃(Ca²⁺通道抑制剂)和50 μmol·L^-1 ATP设计多项处理,分析胞外ATP(eATP)对铝离子(Al³⁺)胁迫引起的植物细胞死亡及其胞内H₂O₂、Ca²⁺的影响,以揭示Al³⁺胁迫下植物调节细胞死亡的可能机制,进一步扩展对eATP功能的认知。结果显示：(1)随着 AlCl₃ 胁迫浓度的提高,细胞死亡水平和胞内H₂O₂水平上升,而胞内Ca²⁺和eATP水平则逐渐降低。(2)外援施加H₂O₂抑制剂 DMTU(二甲基硫脲)和Ca²⁺能够有效缓解AlCl₃诱导的细胞死亡水平的上升;而Ca²⁺通道抑制剂LaCl₃(三氯化镧)则加剧了AlCl₃胁迫下的细胞死亡。(3)在AlCl₃胁迫下对细胞添加外源ATP,能够缓解AlCl₃胁迫下胞内H₂O₂水平上升和Ca²⁺水平下降的同时,并显著降低AlCl₃胁迫导致的细胞死亡。研究表明, Al³⁺以剂量依赖的模式提升细胞死亡和细胞内H₂O₂的水平并降低胞内Ca²⁺和eATP水平,AlCl₃诱导的细胞死亡受到H₂O₂和Ca²⁺水平变化的调节,eATP可以通过调节H₂O₂与Ca²⁺水平缓解AlCl₃诱导的细胞死亡。推测Al³⁺胁迫可能通过抑制钙离子通道而破坏了细胞内H₂O₂和Ca²⁺之间的协同关系,外源ATP对Al³⁺诱导H₂O₂上升的缓解作用可能是由于其提升了细胞的抗氧化能力。     

吉林老白山鱼鳞云杉树轮蓝光强度和轮宽指数与气候响应关系随海拔变化的对比

树轮数据是晚全新世古气候研究中最重要的代用指标。树轮参数各具优缺点, 蓝光强度(BI)是一种获取成本低廉的最大晚材密度(MXD)的光学替代参数, 其蓝色光反射率或强度最小值(256-BI)与相应的MXD值高度相关, 被很多的学者认为是树轮气候学研究中一个具有重要潜能的新兴参数。该研究以吉林老白山3个海拔(900、1 200和1 500 m)的鱼鳞云杉(Picea jezoensis)为例, 分析鱼鳞云杉的BI及轮宽指数(RWI)与气候因子的响应差异, 以期为BI参数在树轮气候学的进一步应用提供参考。结果表明: 不同海拔鱼鳞云杉BI或RWI对气候的响应趋势基本一致。BI与温度主要呈正相关关系, 而RWI与温度主要呈负相关关系, 其中BI与当年夏季及生长季最高温度显著正相关, 而RWI (低、中海拔)与全年平均气温、当年生长季和全年最低温度显著负相关。BI与当年夏季标准化降水蒸散指数(SPEI)显著负相关, RWI与夏季SPEI负相关关系较弱或为正相关; BI和RWI几乎相反的生长-气候关系可能是早、晚材权衡关系的体现。研究区域鱼鳞云杉的BI参数可能与年轮宽度记录不同的气候信号, 在空间尺度上对于当年夏季降水、最高温度以及SPEI的响应好于传统宽度指标。BI与主要气候因子相关关系的时间稳定性好于RWI, 因此, BI在树轮气候学的研究中具有一定的应用潜能。     

凉水自然保护区红松树轮年表建立及特征年分析

以小兴安岭凉水自然保护区红松为样本,运用树木年轮学分析方法,建立了红松树轮宽度年表,并运用相关分析、单年分析探讨了其与该地区气温、降水等气候因子的关系。结果表明,小兴安岭凉水红松生长受气温和降水共同影响,且主要受生长季前冬末春初(2~4月)低温及生长季气温和降水限制:红松年表与上年6、7月份和当年2、4月份均温呈显著正相关,同时其与月最高温和最低温呈现出与月均温相关性相似的趋势,表明红松生长受生长季前及生长季气温影响较大。仅有6月份均温和最高温与红松年表呈现明显的负相关关系,当年3、6月份降水对红松生长产生明显的正影响,说明红松除受生长季气温影响外,还受6月土壤含水率的影响。6月份过高温度加速土壤蒸发、植物蒸腾,与7月相比6月份降雨明显偏少,无法弥补土壤水分损失,致使树木生长受水分胁迫从而形成窄轮。对红松生长最大年(2009年)和最小年(1921年)的单年分析也进一步验证了上述相关分析的结果。我们的发现说明,小兴安岭凉水地区红松树木生长主要受生长季及生长季前气温和降水综合影响,并受6月土壤含水率限制。     

Reconstruction of disturbance history of a typical broad-leaved Pinus koraiensis forest and mechanisms of disturbance occurrence

该文依托于小兴安岭典型阔叶红松(Pinus koraiensis)林9 hm2森林动态监测样地,对样地内林窗边缘主要树种红松和臭冷杉(Abies nephrolepis)进行生长释放判定分析,重建了冠层树木的干扰历史。结果表明:整体上林窗木与非林窗木的生长变化百分率变化规律基本一致,而不同林窗间生长变化百分率存在明显的差异,林窗干扰及其产生的影响存在较大的变异性。在1733–1738、1748–1752、1769–1771、1798–1801、1827–1833、1841–1844、1935–1939及1968–1973年间红松生长释放较强,其中1752、1770、1800、1830、1842、1937及1970年出现了明显的干扰峰;在1889–1904、1932–1938、1947–1973和1986–2005年间臭冷杉生长释放较强,其中1894、1934、1951、1968和1990年出现了明显的干扰峰。红松干扰存在2.0 a、3.5 a、3.8 a、7.3–7.9 a和9.1–18.2 a的显著周期,臭冷杉干扰存在3.5–3.6 a、7.5–48.8 a和65–85 a的显著周期。风干扰是典型阔叶红松林干扰释放的主要因子,异常温度也影响该地区树木生长释放事件。太阳活动通过影响局地风速、温度、降水等气候因子以及其他大尺度气候模态影响林窗动态,可能是小兴安岭典型阔叶红松林的干扰机制之一。     

Genetic portrait of Lisboa immigrant population from Cabo Verde with mitochondrial DNA analysis

Journal of Genetics -     

A specimen of Curculioninae (Curculionidae,Coleoptera) from the Lower Cretaceous,Araripe Basin,north‐eastern Brazil

Abstract: A specimen of Curculionidae (Curculioninae) is described as Arariperhinus monnei gen. et sp. nov. The specimen is preserved on a laminated limestone sample of the Crato Formation (Santana Group), Lower Cretaceous (Aptian–Albian), and was collected from a quarry near Nova Olinda, Chapada do Araripe, State of Ceará, Brazil. The genus is placed in the subfamily Curculioninae because of its strongly convex body and relatively slender rostrum, but mainly by its rounded eyes and lack of a prosternal sulcus and tibial spurs. The very prominent eyes in lateral view, a cylindrical rostrum and a straight posterior margin of ventrite II are strong indications that this fossil belongs to the tribe Anthonomini. However, the claws, which would resolve the exact placement of this fossil, are poorly preserved. Arariperhinus monnei gen. et sp. nov. is distinguishable by the combination of several characters and the first record of the family Curculionidae in the Santana Group; it is the oldest record of a member of the subfamily Curculioninae.     

寒武纪凯里生物群在贵州镇远竹坪地区的发现

贵州东部镇远县竹坪地区付家冲寒武系凯里组中上部Oryctocephalus indicus带至Peronopsis taijiangensis带粉砂质泥岩、泥岩中新发现丰富的多门类化石组合,共计22属及3未定属种,分属海绵动物、节肢动物、腕足动物、软体动物、棘皮动物、腔肠动物,鳃曳动物、水母状动物及藻类9大门类,其中动...