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Many big building fires happened in the past involved burning furniture foam. In some places such as Hong Kong, foams treated with fire retardant additives are only required to test their ignitability under a small flame. It was proposed earlier that the behaviour of furniture foam in flashover fires should be assessed more extensively by a cone calorimeter under high radiative heat fluxes. In this paper, this screening approach is further studied using five samples, including three different pillow foams, one mattress foam and one expensive fire-safe sofa foam. Both thermal and smoke aspects were studied in a cone calorimeter under heat fluxes of 20 kWm-2, 30 kWm-2, 50 kWm-2 and 70 kWm-2. It was observed that all the foam samples were burnt under heat fluxes above 30 kWm-2. Only one pillow foam sample was not ignited under a low incident heat flux of 20 kWm-2, but it morphed into a mixture of solid and liquid. Under heat fluxes above 30 kWm-2, the fire-safe foam burnt vigorously; the burning showed no differences from foam without fire retardant. The fire-safe foam even released more smoke and toxic gases with higher carbon monoxide concentration. From the above cone calorimeter test, foams commonly used in the market can only withstand small match fires to delay ignition time. Foam products should be protected by additional provisions, such as an external cover, to protect them against big fires. [ABSTRACT FROM AUTHOR]

The modern genus Dacrycarpus (Endl.) de Laub. of the family Podocarpaceae, containing nine species, is mainly distributed in tropical mountain rainforests of the southwestern Pacific region, ranging from New Zealand to low‐latitude Asia. This genus has abundant fossil records in both hemispheres, but all the known megafossils were limited to Australasia and South America. Here we report on Dacrycarpus guipingensis sp. nov. from the Miocene Erzitang Formation of Guangxi, South China. This is the first megafossil of Dacrycarpus in the Northern Hemisphere. The new species is represented by mummified dimorphic foliage, ovuliferous shoots, and a male cone with in situ pollen. It resembles the extant Dacrycarpus imbricatus (Blume) de Laub., which is common in rainforests from southern China and northern Myanmar to Fiji. This paper presents the first data on the anatomical structure of seed cone and exine ultrastructure of Dacrycarpus in situ pollen grains from a fossil material by using computed tomography scanning and ultrathin sectioning. For comparative purpose, data on the pollen morphology and ultrastructure were obtained for modern D. imbricatus for the first time. The D. guipingensis fossils strongly suggest the Miocene arrival of Dacrycarpus in Asia from the Southern Hemisphere. Based on the modern ecological niche and related fossil elements, this fossil locality was probably covered by conifer–broad‐leaved mountain rainforests during the Miocene. [ABSTRACT FROM AUTHOR]

Although diverse fossil angiosperms (including their reproductive organs) have been reported from the Early Cretaceous, few of them are well-documented due to poor preservation and limited technologies available to apply. For example, paraffin sectioning, a routine technology applied to reveal the anatomical details of extant plants, was hitherto at most rarely applied to fossil plants. This undermines the comparability between the outcomes of studies on fossil and extant plants, and makes our understanding on plants incomplete and biased. Here, we applied paraffin sectioning technology, in addition to light microscopy, SEM, and TEM, to document a fossil reproductive organ, Xilinia gen. nov., from the Early Cretaceous in Inner Mongolia, China. The anatomical details of this new reproductive organ were documented. Xilinia bears a remarkable resemblance to conifer cones, although its ovules are enclosed in carpels. The paradoxical cone-like morphology of Xilinia appears to represent a transitional snapshot of plant evolution that is absent in extant plants. [ABSTRACT FROM AUTHOR]

Sublepidodendron wusihense (Sze) Sze and Lepidostrobus grabaui Sze were based on compressions from the upper part of the Wutung Formation (Famennian) of Jiangsu, South China. After studying the morphology and anatomy of abundant well-preserved specimens from two localities, Sublepidodendron wusihense and Lepidostrobus grabaui are reconsidered and viewed as Sublepidodendron grabaui (Sze) comb. nov. This plant is an arborescent, heterosporous lycopsid known from trunk, branches and cones. Leaf bases are spirally arranged, fusiform in outline, with a vascular bundle scar and keel. One specimen is known with a cone attached at the tip of a distal branch. The trunk has an intrastelar parenchyma concentration (pith), exarch primary xylem and secondary xylem. The branch anatomy varies from exarch primary xylem with a small, centrally located pith, to a solid exarch primary xylem strand. Based on the morphology and anatomy of both vegetative and reproductive organs, Sublepidodendron grabaui is placed into Sublepidodendraceae ( sensu Kräusel & Weyland, 1949), and Isoëtales ( sensu DiMichele & Bateman, 1996). © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society, 2005, 149, 299–311. [ABSTRACT FROM AUTHOR]

qRT-PCR is a powerful molecular research tool to study the regulation of gene expression. However, to accurately calculate gene expression levels, an experiment should include proper reference genes that show no changes in their expression level. Pinus massoniana, P. hwangshanensis, and their introgression hybrid in Mountain Lushan, China, are an ideal model for studying introgression and speciation. Although some research on reference gene selection for P. massoniana has been reported before, no studies on this subject have been performed where P. massoniana and its introgression hybrid were evaluated simultaneously. Here, we investigated ten genes (upLOC, SDH, ACT, EF, TOC75, DMWD, FBOX, PGK1, UBQ, and CL2417C7) identified from transcriptome data of these two taxa for reference gene potential. These ten genes were then screened across multiple tissues such as cone, young and mature stems, and young needles according to qRT-PCR thermal cycling and dissociation. Correlation coefficient, amplification efficiency, and cycle threshold value (Ct) range were applied to evaluate the reliability of each gene. The stability of candidate reference gene expression was calculated using three algorithms: geNorm, NormFinder, and BestKeeper. Base on the reliability and stability, we then offered a list of genes of recommended and not recommended for seven different tissue type and species. Our results demonstrated that different sample lines require different genes as reference to evaluate. [ABSTRACT FROM AUTHOR]