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Temperature of sporophylls from excised male cones of three species from the Zamiaceae family (Ceratozamia miqueliana, Zamia fairchildiana, and Zamia pumila) and from one species from the Cycadaceae family (Cycas siamensis) was recorded over several days in an environmental chamber. Each species exhibited a different temperature profile. C. miqueliana and Z. fairchildiana were highly thermogenic, whereas C. siamensis and Z. pumila were weakly thermogenic. In C. miqueliana, the temperature of one sporophyll rose to 10 °C above ambient while other sporophylls on the same cone only reached temperatures of 0–3 °C above ambient. Temperature rates among the different cones varied between ≈ 0.01 and 0.09 ∆ °C/h. Temperature profiles of sporophylls of Z. fairchildiana and C. siamensis were reported for the first time. Studies of thermogenesis of single sporophylls in a controlled environment provide accurate temperature measurements. Furthermore, sporophylls can be exposed to different environments and thus improve our understanding of the mechanism of thermogenesis in vivo.

Most cycads have intimate associations with their insect pollinators that parallel those of well-known flowering plants, such as sexually deceptive orchids and the male wasps and bees they deceive. Despite this, the mistaken belief that cycads are mostly wind-pollinated is still commonly expressed. Perhaps as a consequence, cycad–pollinator systems are rarely exemplified in studies of the role of pollinators in plant evolution and diversification. Although first recognised more than a century ago, specialised associations between cycads and their insect pollinators have been elucidated experimentally only in the past few decades. This review covers the history of understanding pollination in cycads, the advances that have been made since the 1980s using field observations and experiments, and analyses of molecular data from the population to phylum level. We outline areas for future research to address how such interactions might have affected speciation and extinctions. We stress that inclusion of cycads in broader considerations of the role of pollinators in plant diversification is important because they are phylogenetically distant from flowering plants and their pollination systems might have evolved independently of one another. This review is timely because cycads are a globally threatened group that might be vulnerable to co-extinction with pollinator loss.

Ceratophila new genus (Erotylidae: Pharaxonothinae) inhabiting male cones of the Mesoamerican cycad genus Ceratozamia Brongniart (Zamiaceae) is described for seven new species and compared to other genera of the Pharaxonothinae. Ceratophila differs from other genera of the Pharaxonothinae in many characters, most notable of which are: lateral pronotal carina thicker anteriorly in lateral view; head with supraocular and transverse occipital lines; elytra lacking a basal bead; and stridulatory files at base of head narrowly separated. Ceratophila has the male genitalia laterally compressed with a short median lobe and flagellum, similar to other Erotylidae. In comparison, the most superficially similar pharaxonothine genus Pharaxonotha Reitter has: lateral pronotal carina thin along entire length; head lacking supraocular lines, but with transverse occipital lines; elytra with distinct basal bead; stridulatory files at base of head widely separated; and unique male genitalia that are dorsoventrally flattened with a long median lobe and flagellum. Ceratophila contains two subgenera, which differ most notably in external characters and sexual dimorphism. Members of Ceratophila ( Ceratophila ), the nominal subgenus, have: more cylindrical bodies, pronotum evenly convex dorsally; the pronotum lacking basal longitudinal grooves on disc; metatibiae that are distinctly triangularly dilated toward apex; and no apparent external sexual dimorphism. In comparison, members of Ceratophila ( Vovidesa ) new subgenus have: dorsoventrally flattened bodies; the pronotum explanate (concave) along lateral margins; the pronotum with basal longitudinal grooves on disc; metatibiae weakly or not dilated toward apex; and with all tibiae in males showing strong sexual dimorphism. Four new species are described within the subgenus Ceratophila : C . ( C .) chemnicki , C . ( C .) gregoryi , C . ( C .) picipennis , C . ( C .) sanchezae; and three new species are described within the subgenus Vovidesa : C . ( V .) chiapensis , C . ( V .) mixeorum , C . ( V .) vazquezi . Keys to genera, subgenera and species of known adults based on morphology are provided.

Two major lineages of beetles inhabit cycad cones in the New World: weevils (Curculionoidea) in the subtribe Allocorynina, including the genera Notorhopalotria Tang and O’Brien, Parallocorynus Voss, Protocorynus O’Brien and Tang and Rhopalotria Chevrolat, and beetles in the family Erotylidae, including the genus Pharaxonotha Reitter. Analysis of the 16S ribosomal RNA (rRNA) mitochondrial gene as well as cladistic analysis of morphological characters of the weevils indicate four major radiations, with a probable origin on the cycad genus Dioon Lindl. and comparatively recent host shifts onto Zamia L. Analysis of the 16S rRNA gene for erotylid beetles indicates that an undescribed genus restricted to New World Ceratozamia Brongn. is the most early-diverging clade, and this lineage is sister to a large radiation of the genus Pharaxonotha onto Zamia, with apparent host shifts onto Dioon and Ceratozamia. Analysis of beetles are in accord with current models of continental drift in the Caribbean basin, support some proposed species groupings of cycads, but not others, and suggest that pollinator type may impact population genetic structure in their host cycads.

The genus Cycadophila Xu, Tang & Skelley (Coleoptera: Erotylidae: Pharaxonothinae) associated with Cycas L. (Cycadacaeae) in Asia is reviewed. Strobilophila, new subgenus, with five species is described: Cycadophila (Strobilophila) assamensis new species, C. (S.) hiepi new species, C. (S.) kwaiensis new species, C. (S.) tansachai new species and C. (S.) yangi new species, all associated with Cycas. For the nominate subgenus Cycadophila eight new species are described, Cycadophila (Cycadophila) abyssa new species, C. (C.) collina new species,C. (C.) samara new species, C. (C.) convexa new species, C. (C.) cyclochasma new species, C. (C.) eurynota new species, C. (C.) papua new species, and C. (C.) torquata new species and four new generic combinations are proposed: C. (C.) vittata (Arrow) new combination, C. (C.) discimaculata (Mader) new combination, C. (C.) intermedia (Chûjô) new combination, and C. (C.) lata (Grouvelle) new combination. Only the first three listed species of the nominate subgenus have known associations with Cycas. Species are distinguished on the basis of morphology and/or by analysis of 16S rRNA gene sequences. The larva of subgenus Strobilophila is described based on individuals collected together with adults and matched with analysis of 16S rRNA gene sequences. Keys to subgenera and species of known adults and larvae are provided.

The mechanical interactions between cells and the extra cellular matrix (ECM) play important roles in many biological processes, including cell proliferation, migration, and differentiation. The cells can probe the stiffness of the ECM and alter their own function accordingly. The objective of this study was to investigate the applicability of a mathematical model by comparing the simulation results generated by the model with published experimental results for the migration of fibroblast, smooth muscle, and glioma cells on substrates. Cell -- substrate traction was assumed to be a nonlinear function of the Young's modulus of the substrate. Simulation parameters were determined so that the tractions and cell speeds agreed with the experimental results. It was shown that the mathematical model could predict the fibroblast migration speed by increasing the Young's modulus of the cell with that of the substrate. Simulation results showed that the smooth muscle cell speed exhibited a biphasic relationship with respect to the substrate stiffness for two fibronectin concentrations, where the limit of elasticity sensing decreased as the fibronectin concentration increased. The numerical results also predicted that the glioma cell migration speed increased with the substrate stiffness. This mathematical model could be used to predict the experimental data for the migration of these different cell types, and is particularly suited for modeling the smooth muscle and glioma cells.

This paper reports on a microfluidic platform to isolate and study avian red blood cells (RBCs) infected to various degrees by the malaria parasite Plasmodium gallinaceum. The experimental findings point to the feasibility of using the morphological changes on the surface of the malaria infected avian RBC (miaRBCs) as biomarkers for diagnosis. A glass substrate with a controlled surface roughness was used as part of a polydimethylsiloxane (PDMS) microfluidic channels. When whole-blood samples were introduced into the channels, the miaRBCs would be preferentially slowed and eventually become immobilized on the roughened surface. The surface lesions and furrow-like structures on the miaRBC surfaces offered a markedly higher probability to interact with the roughened substrate and allowed the cells to become imobilized on the surface. The captured miaRBCs were from blood samples at various degrees of infection at 3.2%, 3.9%, 9.1%, 13.4%, 20.1%, 28%, and 37%. It was observed that the miaRBCs could be selectively captured under a wall shear rate between 2.1 to 3.2 s(-1), which was directly proportional to the flow rate through the channels. This capture rate could be improved by increasing the channel length and finer flow control. It was also found that a roughened glass substrate with ten-point-height larger than the depth of surface lesions and furrow-like structures of miaRBCs showed a substantial enhancement on the number of immobilized infected RBCs. These findings indicated that surface morphologies, including surface lesions and furrow-like structures, can serve as an alternative biomarker for malaria diagnosis.

This work demonstrates a microfluidic platform to study and differentiate avian red blood cells infected to various degrees by the malaria parasite Plasmodium gallinaceum. The preliminary finding points to the feasibility of using the morphological changes on the surface of the malaria infected avian RBC (miaRBC) as biomarkers for diagnosis. By embedding a glass substrate with a controlled surface roughness in a polydimethylsiloxane (PDMS) microfluidic channels, the surface lesions and furrow-like structures on the miaRBC surfaces could interact with the substrate and be separated at 3.2%, 3.9%, 9.1%, 13.4%, and 20.1% infections. It was estimated that the miaRBCs could be selectively captured under a wall shear rate between 2.1 to 3.2 s−1, and could be improved by increasing the channel length and finer flow control.

Microcalorimetric analysis of heat-production by single intact sporophylls from thermogenic male cones of two cycad species (Ceratozamia miqueliana H. Wendl. and Zamia furfuracea L. f.) showed an oscillatory behaviour for three consecutive days during pollen maturation and shedding. In sporophylls from C. rumphii Miq., a weakly thermogenic species with no maximum of heat-production, such oscillations were not detected. The presence of the alternative respiratory pathway in the sporophylls of the male cones of Zamia pumila L. has been demonstrated

The chemistry of the volatile emissions of male cones of four putatively insect-pollinated cycad (Cycadales) species and cones of both sexes of one wind-pollinated cycad species was analysed using GC-MS Zamia furfuracea, Macrozamia moorei, and Encephalartos altensteinii had blends consisting primarily of monoterpenoids, benzenoids, and in two causes, a di-unsaturated aliphatic hydrocarbon, while that of Zamia pumila was dominated by methyl salicylate, with sesquiterpenes and aliphatic hydrocarbons also present. In contrast, the wind-pollinated Cycas rumphii contained a series of highly alcohols, ketones and esters. The compounds classes found in the cycads are potent herbivore deterrents, and there is no apparent difference in this regard between insect- and wind-pollinated species. The results suggest convergent evolution in the gymnospermous cycads and magnoliid angiosperms of the olfactory cues that attract pollinating insects; the data are consistent with the hypothesis that early chemical attractants for pollinators evolved from herbivore deterrents.

A microplatform was designed, fabricated, and tested for demonstrating the propagation of molecular signals through a line of patterned HeLa cells expressing gap junction channels (HeLa Cx43 cells). The microplatform was capable of patterning cells onto a predefined design with lithography and surface chemical treatment. Lucifer Yellow was first used as a fluorescent marker to demonstrate the formation of functional gap junction channels between patterned HeLa Cx43 cells. The cells at one end of the cell line were next chemically stimulated to induce the propagation of intercellular calcium waves along the cell line, which was successfully monitored with Fluo4. The designed microplatform allowed intercellular communication over an arbitrary network topology of cells, which may provide new insight into mechanisms of intercellular communication.

Dans les inflorescences de Sauromatum guttatum, la production de chaleur est induite par l'acide salicyclique a tres faible concentration. Apres purification, le contenu en acide salicylique de nombreuses autres especes est determine grâce a un detecteur de spectrofluorescence. 11 especes productrices de chaleur ainsi que 30 especes non productrices sont etudiees

Asian species assigned to Pharaxonotha Reitter formed a separate clade from New World species of the genus and are distinguished on the basis of morphology and analysis of 16S rRNA gene sequences. Cycadophila, new genus, is described based on a consideration of four Asian species in comparison with New World Pharaxonotha. This new genus includes two new species (Cycadophila debaonica new species and Cycadophila fupingensis new species) and two previously described species (Cycadophila nigra (Gorham) new combination and Cycadophila yunnanensis (Grouvelle) new combination). These latter two may represent species complexes. Lectotypes are designated for Thallis nigra Gorham and Pharaxonotha yunnanensis Grouvelle. Larvae of C. debaonica and C. fupingensis are described based on individuals collected on the cones of Cycas debaoensis Y. C. Zhong & C. J. Chen (Cycadaceae), a cycad native to Guangxi and Yunnan provinces, China.

The taxonomy of the weevils inhabiting male cycad cones in the New World is reviewed. All species belong in a single subtribe, Allocorynina, of the family Belidae, subfamily Oxycoryninae and tribe Oxycorynini and are known to develop only in cones of the cycad genera Dioon and Zamia. Most species of Rhopalotria Chevrolat develop in male cones of Zamia ranging from Mexico, Belize, the Caribbean (Cuba, Isle of Youth, Cayman Islands, Jamaica and the Bahamas) to southern Florida, and one species in those of Dioon spinulosum in Mexico. Rhopalotria consists of three previously described species, two previously described genus-group names (treated herein as subgenera) and four new species described herein: subgenus Allocorynus Sharp with R. calonjei n. sp., R. furfuracea n. sp., R. mollis (Sharp) and R. vovidesi n. sp., and the nominate subgenus Rhopalotria with R. dimidiata Chevrolat, R. meerowi n. sp. and R. slossoni (Schaeffer). The species of Parallocorynus Voss develop only in cones of Dioon in Mexico, and the genus consists of one previously described species, the nominate subgenus and three new subgenera and 11 new species described herein: subgenus Dysicorynus n. subg. with P. andrewsi n. sp. and P. sonorensis n. sp., subgenus Eocorynus n. subg. with P. chemnicki n. sp. and P. schiblii n. sp., subgenus Neocorynus n. subg. with P. iglesiasi n. sp. and P. inexpectatus n. sp., and the nominate subgenus Parallocorynus with P. bicolor (Voss), P. gregoryi n. sp., P. jonesi n. sp., P. norstogi n. sp., P. perezfarrerai n. sp. and P. salasae n. sp. Two new genera are described, Protocorynus with one new species in Honduras, P. bontai, and Notorhopalotria with four new species ranging from Costa Rica to Colombia, N. montgomeryensis, N. panamensis, N. platysoma and N. taylori. Keys to genera, subgenera and species are provided. All of these weevils are believed to be involved in pollination of their host cycads.

The question addressed here is: does the bile duct reactive component of hepatitis C disease progress during the progression of the disease to cirrhosis? The question is important because if the answer to the question is yes, then an important correllated question is: does the bile duct reactive component contribute to the fibrotic change which leads to cirrhosis? The first question is addressed in the present study of a series of liver biopsies taken at the four stages of liver fibrosis in patients with hepatitis C. Sixty-four patients with hepatitis who had been biopsied for staging purposes were reviewed retrospectively. The liver biopsies were routinely stained with antibodies for liver cells, bile duct cells, activated stellate cells and cells in S phase of the cell cycle and histochemical stains for collagen and basement membrane. Selective biopsies were stained for stem cells and oval cells. There was a progressive increase in metaplastic bile ductules but the increase did not reach a significant level until stages III and IV of fibrosis. There was a positive correlation between the number of ductules formed and the stage of liver fibrosis. The incidence of proliferating metaplastic ductules was low and did not change significantly during the progression of the stage of the fibrosis. Stains for oval cells and stem cells were negative. It is concluded that the answer to the question posed is: bile ductule reaction does increase during the development of cirrhosis caused by hepatitis C but the increase is due to bile ductular metaplasia, not due to proliferation.

The fatty acid profiles of various organs of the thermogenic inflorescence of Sauromatum guttatum and of the sporophylls of thermogenic male cones of two cycad species (Encephalartos ferox and Dioon edule var edule and var angustifolium) were determined by gas chromatography. During anthesis, palmitate (16:0), oleate [18:1 (9)], cis-vaccinate [18:1 (11)], and linoleate [18:2 (9, 12)] were the most abundant fatty acids in the Sauromatum appendix. cis-Vaccinic acid, a positional isomer of oleic acid, was identified by comparing its retention time on a gas chromatography column and its mass spectrum to an authentic compound. The percentage of oleic acid from total fatty acids dropped from about 9 in the morning 3 d before heat production to 6 in the morning 2 d before heat production. At this time, the percentage of cis-vaccinic acid increased from 3 to 11%, and then remained at this level until the inflorescence dried and died. Palmitoleic acid [16:1 (9)], the common precursor of cis-vaccinic acid, is a minor component of total fatty acids. In six other organs of the Sauromatum inflorescence including thermogenic organs, such as male flowers and lower spadix, palmitate, oleate, and linoleate were prevalent but cis-vaccinate was not. The thermogenic male cones of the two cycad species were rich in palmitic, oleic, and linolenic acids. The level of cis-vaccinic acid in these organs was less than 0.5%.

A new species of cycad allied to theC. circinalis group,Cycas pranburiensis, is described from the southeast karst area of Thailand near Pranburi, Prachuap Khiri Khan province. It is distinguished by its short leaves with broad, coriaceous leaflets and mostly unarmed petioles, and the extended, gently curved sterile apices of the microsporophylls. The cone beetle fauna of the new species, believed to be involved in pollination, is distinct from that of other southeast Asian species ofCycas.

TANG, W. (Fairchild Tropical Garden, 10901 Old Cutler Road, Miami, FL 33156). Reproduction in the cycad Zamia pumila in a fire-climax habitat: an eight-year study. Bull. Torrey Bot. Club 117: 368-374, 1990.-Zamia pumila L. (Cycadales) is a long-lived dioecious plant with a herb-like habit common in the fire-climax pine forests of southeast Florida. To evaluate sex-related differences in its reproductive strategy, frequency and size of reproductive effort were monitored for males and females in a population over an 8-year period after fire. Eightyseven percent of the non-seedling plants in the population coned during the study period, revealing a sex ratio of 1.8 male/female. Coning sex ratios for each season varied from 2.7-12 male/female. On average males coned once every 1.6 years and produced a mean of 1.45 cones/ yr while females coned once every 3.7 yr with a mean of 0.35 cones/yr. Energy investment in reproduction over the entire study period, however, was on average 3.4 times greater for females. Leaf and cone production declined by the 8th and 9th year after fire, as shrubs recovering from fire damage shaded the habitat. Reproduction in Z. pumila is compared with that in other iteroparous dioecious plants and animals in which there is divergent selection between the sexes for reproductive success.

Thermogenesis occurs in the strobili of 42 of 43 species in the 10 genera of cycads, indicating a wide-spread phenomenon in this group. Heat production generally follows a circadian rhythm, and its strength and duration are positively correlated with strobili size. Male strobili contain high concentrations of starch that may supply the energy for thermogenesis. Strobili of all examined species release odors that are sweet, resiny, or musty. Heat production in the strobili may help to volatilize odors that attract insects for pollination.

Seed dispersal of the herbaceous cycad Zamia pumila was studied in the rockland pine forests of southeast Florida. Dispersal activity was found to occur over 6 months and was concentrated in two periods: after seed ripening and prior to seed germination. Seed mass and pulp-to-seed ratios were positively correlated with dispersal success at one study site. Seed shadows were generally asymmetrical in direction, with seeds tending to be deposited under nearby shrubs. Seed germination and seedling establishment is higher in shade than in sun, suggesting that the lower light intensities under shrubs are safe sites for seeds and seedlings.

High starch concentrations in the sporophylls of male cones of five species of cycad and their depletion during their heat-producing phase of development suggest that starch is a major fuel source for thermogenesis in these plants. Carbon- 1 3/carbon- 12 ratio analyses of respired C02, starch, and lipids in a male cone of one of these species, Macrozamia moorei F. Muell., indicate that although starch is a major contributor to respiration, lipids are also an important respiratory substrate. THERMOGENESIS, although uncommon in plants in general, has been shown to occur in the flowers or inflorescences of diverse types of plants, including many aroids (Meeuse, 1975), the water lily Victoria sp. (Meeuse, 1975), some palms (Schroeder, 1978), and many species of

A wind and insect exclusion pollination experiment was conducted in a wild population of the cycad Zamia pumila L. in Florida. Cones from which insects but not wind were excluded produced no viable seeds, while cones from which wind but not insects were excluded produced abundant viable seeds. Two beetle species have been identified which may be effecting pollination. Adults and larvae of both beetles are found abundantly on the male cones, and adults of both species and larvae of one species are found occasionally on female cones. Z. pumila produces sugar and amino acid-rich micropyle droplets which may serve as pollinator rewards. Mimicry of resource-rich male cones by female cones and the use of cones as refuges between mating and feeding bouts may account for beetle movement from male to female cones.