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Tobleria bicuspis, a coniferophyte seed cone, is described from the Jambi Palaeoflora, Sumatra of Asselian (early Permian) age. A morphometric analysis based on cones, paired fertile units, and fertile and sterile scales, demonstrates their close relationship. Small paired fertile units occur mainly in cones. Medium-sized paired fertile units occur mainly on scales. And large paired fertile units are mainly dispersed. The cones are considered female and the paired fertile units are considered to represent the seeds. The cones are composed of helicoidal, bilaterally symmetrical and deeply incised scales with paired seeds. A comparison can be made with the Voltziales female taxon Schizolepis from the Triassic and Jurassic. Tobleria is regarded as having a voltzian Voltziales affinity and dates from approximately 16 to 26 million years before any other such cones.

Dicranophyllum gallicum Grand’Eury is described by means of a morphometric analysis of eighty two samples from various old and new localities in western and central Europe. Stem, leaf cushions, leaf scars, leaves, axillary structures and potential seeds are described in detail, and discussed in comparison to earlier studies. The encountered variability in size and structure is shown to be higher than what was described earlier. The organisation of the leaf cushion and scar density vary gradually with the stem width, while stratigraphic position and ecology do not relate to it. It is concluded that the described variability represents an ontogenetic feature rather than a phylogenetic or ecologic one. The juvenile plants are characterised by small stems, a high leaf scar density and elongated leaf cushions with a dominant apical field, while mature specimens are characterized by a wide stem, a relatively low leaf scar density and relatively wide leaf cushions with a pronounced basal field. Axillary shoots and potential seeds of D. gallicum are described and illustrated in detail for the first time. A reconstruction based on the studied material is presented.

The Zonguldak – Amasra Coal Basin in north-western Turkey has Carboniferous terrestrial deposits ranging in age from Arnsbergian to late Asturian or possibly early Cantabrian. They yield macrofloras that allow detailed biostratigraphical correlations with sequences in Europe. These correlations suggest there are substantial gaps in the Zonguldak – Amasra succession, with middle to upper Namurian, upper Langsettian, Duckmantian and lower Asturian strata apparently being missing. This in turn suggests the area was subjected to significant tectonic instability during Pennsylvanian (late Carboniferous) times and that this might have been instrumental in initiating the progressive change in composition and eventual collapse of the coal swamp biome across Variscan Euramerica during Westphalian times.

Tobleria bicuspis, a coniferophyte seed cone, is described from the Jambi Palaeoflora, Sumatra of Asselian (early Permian) age. A morphometric analysis based on cones, paired fertile units, and fertile and sterile scales, demonstrates their close relationship. Small paired fertile units occur mainly in cones. Mediumsized paired fertile units occur mainly on scales. And large paired fertile units are mainly dispersed. The cones are considered female and the paired fertile units are considered to represent the seeds. The cones are composed of helicoidal, bilaterally symmetrical and deeply incised scales with paired seeds. A comparison can be made with the Voltziales female taxon Schizolepis from the Triassic and Jurassic. Tobleria is regarded as having a voltzian Voltziales affinity and dates from approximately 16 to 26 million years before any other such cones. [ABSTRACT FROM AUTHOR]

The Merangin River section in Sumatra exposes the Permian Mengkarang Formation. This is composed of eight intervals showing upwards fining and thinning of volcanic tuffs and volcaniclastic sedimentary rocks, overlain by their reworked alluvial products. Isotopic age evaluation of the top and the base of the Merangin section indicates an average duration of 630,000 years (from 296.77 ± 0.04 to 296.14 ± 0.09 Ma). Extrapolation of the eight intervals onto neighbouring tributaries by using earlier geological studies and the strike of the beds allows for the integration of the data assembled in recent expeditions, and those from 1925, leading to the lithostratigraphic assignment of more than 2,000 palaeobotanical specimens. The compilation of all assembled palaeobotanical data indicates there is a change in composition from a palaeoflora dominated by Cordaites, ferns, or club mosses to one in which seed ferns were dominant. These changes, coupled to eustatic sea‐level fluctuations, indicate a climatic origin for this transition and extend palaeofloral trends perceived earlier in Far Western low latitudes to the Far Eastern Palaeotethys. [ABSTRACT FROM AUTHOR]

The Early Permian (Asselian) Mengkarang Formation of the western Jambi Province, Sumatra, is well exposed in the valley of the Merangin River. No consensus regarding the depositional environment of this section had been reached hitherto. This section preserves abundant evidence of a Permian forest, named the Merangin Fossil Forest herein, which grew at the foot of an active volcano, where pyroclastic flows often made way and destroyed the vegetation and where epiclastic reworked pyroclastics rapidly entombed the vegetation. The present assessment is based on a detailed study of three localities using multiple lines of evidence, including petrography, silica typing including hot cathodoluminescence microscopy and spectroscopy, and palynofacies analysis. In situ Agathoxylon was near enough to the volcanic slope to be buried rapidly, shallow enough to avoid extreme crystallization in the lumina, and far enough from the metamorphic centre not to get recrystallized. All these combined contingencies make this a most unique find that provides significant insights into a rarely studied palaeoecological setting from the Early Permian. [ABSTRACT FROM AUTHOR]

Dicranophyllum gallicum Grand'Eury is described by means of a morphometric analysis of eighty two samples from various old and new localities in western and central Europe. Stem, leaf cushions, leaf scars, leaves, axillary structures and potential seeds are described in detail, and discussed in comparison to earlier studies. The encountered variability in size and structure is shown to be higher than what was described earlier. The organisation of the leaf cushion and scar density vary gradually with the stem width, while stratigraphic position and ecology do not relate to it. It is concluded that the described variability represents an ontogenetic feature rather than a phylogenetic or ecologic one. The juvenile plants are characterised by small stems, a high leaf scar density and elongated leaf cushions with a dominant apical field, while mature specimens are characterized by a wide stem, a relatively low leaf scar density and relatively wide leaf cushions with a pronounced basal field. Axillary shoots and potential seeds of D. gallicum are described and illustrated in detail for the first time. A reconstruction based on the studied material is presented. [ABSTRACT FROM AUTHOR]

Although araucarioid wood is poor in diagnostic characters, well in excess of 200 Late Paleozoic species have been described. This study presents a largescale anatomical analysis of this wood type based on the fossil wood collections from the Early Permian Mengkarang Formation of Sumatra, Indonesia. Principal Component Analysis visualisation, in conjunction with uni- and multivariate statistical analyses clearly show the wood from the Mengkarang Formation to be a contiguous micromorphological unit in which no individual species can be distinguished. Pycnoxylic wood species described previously from this collection or other collections from the Mengkarang Formation fall within the larger variability described here. Based on comparison with wood from modern-day Araucariaceae, the Early Permian specimens can be differentiated from extant (but unrelated) "araucarioids" by a few (continuous) characters. [ABSTRACT FROM AUTHOR]

The Zonguldak -- Amasra Coal Basin in north-westem Turkey has Carboniferous terrestrial deposits ranging in age from Arnsbergian to late Asturian or possibly early Cantabrian. They yield macrofloras that allow detailed biostratigraphical correlations with sequences in Europe. These correlations suggest there are substantial gaps in the Zonguldak- Amasra succession, with middle to upper Namurian, upper Langsettian, Duckmantian and lower Asturian strata apparently being missing. This in turn suggests the area was subjected to significant tectonic instability during Pennsylvanian (late Carboniferous) times and that this might have been instrumental in initiating the progressive change in composition and eventual collapse of the coal swamp biome across Variscan Euramerica during Westphalian times. [ABSTRACT FROM AUTHOR]

The gigantopterids are a pan-palaeotropical Late Palaeozoic (to Early Mesozoic) plant group with unknown affiliations. Two gigantopterid species, both sole representatives of their respective genera, are known from the Early Permian Mengkarang Formation of Jambi (Sumatra, Indonesia). Through an emendation of the Jambi gigantopterids, based on the old and newly collected material, and a subsequent analysis of the leaf morphology of several gigantopterid genera, we conclude that the Jambi species are similar to the other gigantopterids, but do not appear to be related to them directly. We propose a possible scenario for the evolution of gigantopterid leaf morphology, based on marginal leaf growth, with implications for the validity of the gigantopterids as a natural group. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 161, 302–328. [ABSTRACT FROM AUTHOR]

A preliminary taxonomic revision of the Early Permian Jambi flora results in a lower number of taxa, a number of new determinations and several new combinations (Dicranophyllum molle (Jongmans & Gothan) comb. nov., Oligocarpia posthumii (Jongmans & Gothan) nov. comb., Callipteridium strictinervis (Jongmans & Gothan) comb. nov.). Cones containing the bicuspidate seeds Tobleria bicuspis are recorded for the first time. The exact stratigraphic position of the Jambi flora is unknown, but brachiopods and fusulinids indicate an Early Permian age. Comparisons with the East Asian Permian floras of the Cathaysian realm indicate that the Jambi palaeoflora can best be compared to a relatively xeric Cathaysian flora, possibly indicative of relatively high latitude. [ABSTRACT FROM AUTHOR]

Dense linear algebra libraries need to cope efficiently with a range of input problem sizes and shapes. Inherently this means that parallel implementations have to exploit parallelism wherever it is present. While OpenMP allows relatively fine grain parallelism to be exploited in a shared memory environment it currently lacks features to make it easy to partition computation over multiple array indices or to overlap sequential and parallel computations. The inherent flexible nature of shared memory paradigms such as OpenMP poses other difficulties when it becomes necessary to optimise performance across successive parallel library calls. Notions borrowed from distributed memory paradigms, such as explicit data distributions help address some of these problems, but the focus on data rather than work distribution appears misplaced in an SMP context. [ABSTRACT FROM AUTHOR]

The article contrasts differing examples of jumbled shell beds preserved around islands to help clarify issues of provenance. The Early Permian Mengkarang Formation in Sumatra, Indonesia shows an association of nektic cephalopods overlying a fine grained ash containing a diverse association of terrestrial pollen representing hydrophytic, hygrophytic and mesic to xeric plants. A Middle Miocene formation in the Grenadines contains deeper water taxa preserved in association with land snails, hermatypic scleractinians, algal balls and planktic pteropods.

Tobleriabicuspis , a coniferophyte seed cone, is described from the Jambi Palaeoflora, Sumatra of Asselian (early Permian) age. A morphometric analysis based on cones, paired fertile units, and fertile and sterile scales, demonstrates their close relationship. Small paired fertile units occur mainly in cones. Medium-sized paired fertile units occur mainly on scales. And large paired fertile units are mainly dispersed. The cones are considered female and the paired fertile units are considered to represent the seeds. The cones are composed of helicoidal, bilaterally symmetrical and deeply incised scales with paired seeds. A comparison can be made with the Voltziales female taxon Schizolepis from the Triassic and Jurassic. Tobleria is regarded as having a voltzian Voltziales affinity and dates from approximately 16 to 26 million years before any other such cones.

Dicranophyllum gallicum Grand'Eury is described by means of a morphometric analysis of eighty two samples from various old and new localities in western and central Europe. Stem, leaf cushions, leaf scars, leaves, axillary structures and potential seeds are described in detail, and discussed in comparison to earlier studies. The encountered variability in size and structure is shown to be higher than what was described earlier. The organisation of the leaf cushion and scar density vary gradually with the stem width, while stratigraphic position and ecology do not relate to it. It is concluded that the described variability represents an ontogenetic feature rather than a phylogenetic or ecologic one. The juvenile plants are characterised by small stems, a high leaf scar density and elongated leaf cushions with a dominant apical field, while mature specimens are characterized by a wide stem, a relatively low leaf scar density and relatively wide leaf cushions with a pronounced basal field. Axillary shoots and potential seeds of D. gallicum are described and illustrated in detail for the first time. A reconstruction based on the studied material is presented.

Background: Hemianopia and strabismus leads to severe disturbance of visual orientation and diplopia under binocular conditions if the deviated eye has a normal retinal localization., Subjects and Methods: Four cases with homonymous (two) and bitemporal (two) hemianopia and strabismus will be described with respect to binocular visual field and diplopia/confusion. All of them were recommended for strabismus surgery. Preoperatively, prism adaptation test was carried out to analyze functional results and fusional competence. In three of the four cases, strabismus surgery was successfully performed to avoid diplopia/confusion. All three patients revealed normal retinal correspondence. Furthermore, in two cases surgery led to an extension of binocular visual field; in one case with a bitemporal hemianopia and hemifield-slide phenomenon, blurred central vision and reading problems reduced significantly postoperatively. In one patient with anomalous retinal correspondence due to early childhood trauma exotropia led to an extension of the binocular visual field. In this case, strabismus surgery would have been unfavourable., Results: Case 1 showed a homonymous hemianopia to the left and acquired exotropia of the right eye, leading to binocular diplopia. Case 2 with homonymous hemianopia to the right and exotropia of right eye revealed anomalous retinal correspondence after history of perinatal brain injury, resulting in absence of diplopia and enlargement of visual field to the right. Cases 3 and 4 with bitemporal hemianopia suffered from sensory disturbances caused by additional acquired strabismus. The exodeviation of the right eye in case 3 led to a restriction of binocular visual field with overlap of the nasal parts causing diplopia, whereas the esodeviation of case 4 resulted in a "gap" between the nasal parts (blind area)., Conclusion: Depending on the extent of visual field defects and on retinal correspondence, functional consequences for binocular vision and binocular visual field should be considered prior to surgery. In normal retinal correspondence, strabismus surgery will be indicated in most cases because of diplopia. However, surgery might result in a reduction of binocular visual field. Preoperatively, it is important to map monocular and binocular visual fields, to examine retinal correspondence, and to undertake prism adaptation test to imitate the postoperative functional result and risk of double vision.

Background: We report on an eight-year-old boy, who was presented in our clinic because of head turn. The cause of the tortecollis (ocular or general) in this case was and still cannot be explained. Only by applying extensive prism adaptation tests it was possible to prove the ocular character of the head turn., Case Report: An eight-year-old boy with Brown's syndrome was referred to us because of a head tilt to the left side. Six months previously surgery on the M. obl. superior of the right eye was performed in another clinic. No improvement of the head tilt could be observed after the operation. In addition, an exotropia became decompensated. Under a 3-day occlusion of one eye, no change of the head turn and the squint could be measured. No other cause of the head turn could be found by an orthopaedist and a paediatrist. Under a prism of 20 cm/m basis in and 10 cm/m basis against the positive vertical deviation, the head tilt decreased, so that we decided to do a second surgery. The head tilting had not resumed at one year after the surgery., Conclusions: Although the initial diagnostic findings ruled out an ocular cause, it was possible to lessen the head tilting with the aid of the prism adaptation test. This case study emphasises the usefulness of a prism adaptation test of several days duration in order to validate an ocular cause of head turn and to determine an adequate indication for surgery.