Oldest known non-marine diatoms (Aulacoseira) from the uppermost Cretaceous Deccan Intertrappean beds and Lameta Formation of India

Non-marine diatoms occur in the Deccan Intertrappean beds (Upper Cretaceous) of Mohgaon-Kalan, Chhindwara District, Madhya Pradesh and Pisdura, Lameta Formation (Upper Cretaceous), Maharashtra, India. This represents the oldest record of non-marine diatoms yet reported and the oldest from the Indian subcontinent. The diatoms were recovered from thin sections of chert and dinosaur coprolites by random fracturing. Solitary forms are the most common but colonial filaments up to five cells were also observed. Based on the morphological characters, the diatoms are identified as Aulacoseira Thwaites. The Lower Cretaceous marine diatom genus Archepyrgus Gersonde and Harwood also resembles Aulacoseira in general morphological characters and it seems that Aulacoseira evolved from Archepyrgus and migrated to the non-marine realm.     

The effect of variation of the lingual shape of mandibular complete dentures on lingual resistance to lifting forces

Increasing life expectancy, age related reduction in adaptability and progressive severe mandibular resorption all add to the importance of any factor improving the prosthetic success. Objective : To investigate the effect of two different lingual shapes of lower dentures on patients' ability to resist lifting forces. Design : Tongue pressures on the lingual surface of complete mandibular experimental dentures were recorded from mid-line, premolar and molar transducers. Two experimental prostheses were fabricated for each subject: one conventionally contoured, the other formed by piezography. Setting : A clinical research laboratory. Subjects Five experienced complete denture wearers between age 64 and 82 years. Intervention Lifting forces were applied at the midline, left and right premolar sites in random order. Main outcome measures : Peak resistance to lifting forces and lingual pressures used during these tests. Results : Lingual pressures exerted anteriorly were dramatically higher than those on premolar and molar surfaces. Significantly higher pressures were used to resist lifting forces applied to piezographically than conventionally formed contours; correspondingly, significantly higher lifting peak forces were, on average, resisted. Conclusions : Providing a lower denture with a piezographically produced lingual surface was shown, in this preliminary study, to enhance tongue retentive ability over a conventional design. It seems reasonable to maximise retentive potential with oblique sublingual polished surfaces and minimise the adaptive demand, particularly for older patients, by using a piezographic technique which “customises” the contour and precludes over-extension.     

Conodont biostratigraphy of Tournaisian shallow-water carbonates in central Guangxi,South China

The conodont faunas of Tournaisian shallow-water carbonates from central Guangxi are described mainly for biostratigraphic purposes. A complete series of samples was collected from the Long’an and Du’an formations in the Long’an section. These formations are characterized by lime-mudstone, skeletal and peloidal wackestone, packstone and grainstone with typical shallow-water biota. Overall, these samples produced 809 identifiable Pl elements, belonging to 50 species in 11 genera, of which one species and one subspecies are new. The fauna enables the establishment of seven biozones (in ascending order): Polygnathus spicatus, Siphonodella homosimplex, S. sinensis, S. dasaibaensis, Polygnathus communis carina Acme, Gnathodus cuneiformis, and P. communis porcatus zones. Based on these new collections from central Guangxi and on data from the literature, a conflated Tournaisian conodont zonation is proposed for shallow-water successions in South China. Most of the conodont zones correlate well with their counterparts recognized in Western Europe, which may be of greater significance in stratigraphic correlation than previously thought.     

Lower Carboniferous (middle Visean) foraminifers and algae from an interior sea,Southern Carnarvon Basin,Australia

A moderate diversity biota of foraminifers, algae and calcareous microproblematica is recorded from the Lower Carboniferous Yindagindy Formation within the intracratonic Southern Carnarvon Basin in Western Australia. Very shallow metahaline to hypersaline conditions are suggested. The palaeobotanical components are sporadic calcitarcha, tuberitinaceans, codiaceans Orthriosiphon? sp. 1, dasycladaleans? Koninckopora tenuiramosa, and algosponges Issinella devonica, Serrisinella cf. serrensis, Issinella? sp. 1, Kamaena cf. awirsi, Proninella? sp. and Stacheoides spp. The foraminiferal assemblage is dominated by a new koktjubinid taxon: Praekoktjubina yindagindyensis nov. gen., nov. sp. Subordinate associated foraminifers are more sporadic Salpingothurammina? sp. 1, Plectinopsis michelseni nov. gen., nov. sp., Rectopravina multifida nov. gen., nov. sp. (with 4 morphotypes), and scarce Endothyra spp. Despite many of these taxa being endemic, a middle Visean age is probable, based on: (1) the maximum global geographic extent of K. tenuiramosa reached during the middle Visean, (2) the disappearance of Plectinopsis nov. gen. in Palaeotethys and the Urals, and (3) the first occurrence of Praekoktjubina nov. gen. in Palaeotethys. An age no older than the middle Visean is supported by sparse conodonts from the Formation and comparison to episodes of carbonate deposition in the Bonaparte Basin, further north in the East Gondwana rift system. Absence of middle Visean archaediscoids may be due to high salinity. The following algal and foraminiferal families and superfamilies are emended: Scribroporellaceae (a lectotype is selected for Orthriosiphon saskatchewanense); Palaeospiroplectamminidae (due to the creation of Plectinopsis nov. gen.); Haplophragminoidea (due to the creation of Rectopravina nov. gen.); and Globivalvulinoidea and Koktjubinidae (due to the creation of Praekoktjubina nov. gen.).     

The effects of P2X7 receptor antagonists on the formation and function of human osteoclasts in vitro

The P2X7 receptor (P2X7R) has been implicated in the process of multinucleation and cell fusion. We have previously demonstrated that blockade of P2X7Rs on osteoclast precursors using a blocking antibody inhibited multinucleated osteoclast formation in vitro, but that P2X7R KO mice maintain the ability to form multinucleated osteoclasts. This apparent contradiction of the role the P2X7R plays in multinucleation has prompted us to examine the effect of the most commonly used and recently available P2X7R antagonists on osteoclast formation and function. When added to recombinant RANKL and M-CSF human blood monocytes cultures, all but one compound, decreased the formation and function of multinucleated TRAP-positive osteoclasts in a concentration-dependent manner. These data provide further evidence for the role of the P2X7R in the formation of functional human multinucleated osteoclasts and highlight the importance of selection of antagonists for use in long-term experiments.     

The costal skeleton of Homo antecessor: preliminary results

The Lower Pleistocene TD6 level at the Gran Dolina site in the Sierra de Atapuerca (Burgos, Spain) has yielded nine ribs that represent a minimum of three individuals of the species, Homo antecessor. We present a detailed morphological and metric study of these costal elements, including the siding and anatomical position of all of the rib remains. The adult or nearly adult ribs are also metrically compared with other fossil hominins and with modern comparative samples. The costal elements recovered to date from the TD6 level at Gran Dolina can neither confirm nor reject the hypothesis that H. antecessor had a large thorax, similar to that of Neandertals. However, the fragmentary evidence of the H. antecessor thoracic skeleton is not inconsistent with this suggestion based on other skeletal elements, such as clavicles.

Resumen

En el nivel TD6 del Pleistoceno inferior del yacimiento de Gran Dolina, en la Sierra de Atapuerca (Burgos, España) se han recuperado nueve costillas que pertenecen a un mínimo de tres individuos de la especie Homo antecessor. Presentamos un detallado estudio métrico y morfológico incluyendo el lado y la determinación anatómica. Las costillas pertenecientes a individuos adultos o casi adultos también son comparadas métricamente a muestras modernas de comparación y otros homininos fósiles. Basándonos en el registro de costillas de Homo antecessor recuperado hasta el momento no podemos probar ni refutar la hipótesis de que esta especie presentaba un tórax grande similar al de los Neandertales. Sin embargo, el registro de costillas no es inconsistente con la hipótesis de un tórax grande como sugiere la gran longitud de sus clavículas.     

广西泥盆纪早埃姆斯期郁江组Heterophaulactis Yu,1974的再研究(英文)

Heterophaulactis Yu是作者建立并发表于1974年的一四射珊瑚属,产自广西郁江沿岸、南宁至六景一带的泥盆纪郁江组,其时代属早埃姆斯期牙形刺kitabacus带(前dehiscens带)。对此珊瑚属再行研究,是出于:1)发表在"中国南方泥盆系的新进展"一文,是与其它门类化石共同作为划分和对比地层的化石依据,只限于中文简短描述,对化石图影的展示也有严格的数量限制。尽管此属己被收录在Hill(1981)主编的古生物专论的珊瑚分册中,也只是简短的英文描述和有限的图影,未能充分展示其骨骼演变特征;2)此属的分类位置、科的归属及与相关属的属征比较与讨论,当初均未交待,应予阐明;3)Heterophaulactis属的地理分布广,遍及滇桂两省,通过再研究,其产地已扩展至中国西北地区;其地层分布又有一定的时限性,在广西仅限于郁江组下部的石州段,时代为kitaba-cus带,其它地区也仅见于下泥盆统。文中对Heterophaulactis属的模式种,Heterophaulactis semicrassa的骨骼特征及个体发育过程中的演变均作详细的英文描述和图影展示;与相关属比较之后,认为与本属关系最为密切的是产于西秦岭山区下泥盆统、发表在西北区化石图册上的有些属种,其中的有些属种可以归于本属。文中还记述一新建种Heterophaulactis yujiangense sp.nov.。文章对Heterophaulactis的分类位置和科的归属也有详细比较讨论,认为它是源出自志留纪Pycnactis—Phaulactis的演化序列,应归属于Lykophyllidae Wedekind,1927科。对Miroelasmatinae Cao,1983亚科的原始定义作全面修订后,把它归为Lykophyllidae Wedekind,1927科下的一个亚科;在对化石图册及相关文献上记述的产自西秦岭区下泥盆统四射珊瑚属种的全面修订之前,暂把以下各属置于此亚科:Heterophaulactis Yu,Miroelasma Cao,Qinlingophyllum Cao,Wenxianophyllum Cao,Protaulacophy-llum Cao,Bethanyphyllum sensu Cao,Aulacophyllum sensu Cao和Aulacophyllum sensu Zhang。     

浙江天台晚白垩世巨型长形蛋科一新属及巨型长形蛋科的分类订正

浙江天台盆地上白垩统赤城山组发现的巨型长形蛋类可鉴定为西峡巨型长形蛋(Macroelongatoolithusxi xiaensis)和一新蛋属、新蛋种——桥下巨型纺锤蛋(Megafusoolithus qiaoxiaensis oogen.etoosp.nov.)。西峡巨型长形蛋此前仅发现于河南西峡盆地,其特征为个体巨大(35cm),蛋壳外表面具瘤点状纹饰,蛋壳锥体层与柱状层界线明显,呈波浪形,锥体层与柱状层厚度之比为1:5—1:2。已记述的产自天台的张氏巨型长形蛋(M.zhangi)和产自河南西峡盆地的西峡长圆柱蛋(Longiteresoolithus xixiaensis)均为西峡巨型长形蛋的同物异名。桥下巨型纺锤蛋的特征包括蛋壳中部外表面具有棱脊状纹饰,蛋壳锥体层与柱状层界线不明显,二者厚度之比近1:3,这些特征区别于巨型长形蛋属。目前已知巨型长形蛋科仅包含巨型长形蛋属和巨型纺锤蛋属,订正的科征为:蛋化石巨大,长径大于35cm;蛋长形,两端大致对称,长宽之比约为3:1;蛋化石在蛋窝中一般两枚为一组,呈单层圆环状排列,蛋窝直径近3m;蛋壳外表面具瘤点状或棱脊状纹饰,蛋壳由锥体层与柱状层组成。这些特征明显区别于其他类型的蛋化石,因此它们代表了一个独立的蛋科:巨型长形蛋科(Macroelongatoolithidae)。     

Axial nature of the cupule‐bearing organ in Caytoniales

Abstract Caytoniales are an important group of seed plants, and the nature of their female reproductive organ may influence interpretations of the seed plant phylogeny and the origin of angiosperms. Although not convincingly demonstrated by clear evidence, cupules on previously described specimens were interpreted as being distichously arranged, implying that the cupule‐bearing organ in Caytoniales was a pinnate megasporophyll. Here a female reproductive organ of Paracaytonia hongtaoi gen. et sp. nov. (Caytoniales) is reported from Liaoning, China. The well preserved specimen clearly shows a spiral arrangement of cupules along the reproductive axis, suggesting that the cupule‐bearing organ in Caytoniales is not a megasporophyll but a branch. This new information on the axial nature of the cupule‐bearing organ in Caytoniales has significant implications on the placement of Caytoniales in the seed plant phylogeny and interpretation of the relationship between Caytoniales and angiosperms.