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The preconception, pregnancy and immediate postpartum and newborn periods are times for mothers and their offspring when they are especially vulnerable to major stressors – those that are sudden and unexpected and those that are chronic. Their adverse effects can transcend generations. Stressors can include natural disasters or political stressors such as conflict and/or migration. Considerable evidence has accumulated demonstrating the adverse effects of natural disasters on pregnancy outcomes and developmental trajectories. However, beyond tracking outcomes, the time has arrived for gathering more information related to identifying mechanisms, predicting risk and developing stress-reducing and resilience-building interventions to improve outcomes. Further, we need to learn how to encapsulate both the quantitative and qualitative information available and share it with communities and authorities to mitigate the adverse developmental effects of future disasters, conflicts and migrations. This article briefly reviews prenatal maternal stress and identifies three contemporary situations (wildfire in Fort McMurray, Alberta, Canada; hurricane Harvey in Houston, USA and transgenerational and migrant stress in Pforzheim, Germany) where current studies are being established by Canadian investigators to test an intervention. The experiences from these efforts are related along with attempts to involve communities in the studies and share the new knowledge to plan for future disasters or tragedies.
Two in situ experimental methods are presented in which dust particles are used to determine the extent of the sheath and gain information about the time-averaged electric force profile within a radio frequency (RF) plasma sheath. These methods are advantageous because they are not only simple and quick to carry out, but they also can be performed using standard dusty plasma experimental equipment. In the first method, dust particles are tracked as they fall through the plasma towards the lower electrode. These trajectories are then used to determine the electric force on the particle as a function of height as well as the extent of the sheath. In the second method, dust particle levitation height is measured across a wide range of RF voltages. Similarities were observed between the two experiments, but in order to understand the underlying physics behind these observations, the same conditions were replicated using a self-consistent fluid model. Through comparison of the fluid model and experimental results, it is shown that the particles exhibiting a levitation height that is independent of RF voltage indicate the sheath edge – the boundary between the quasineutral bulk plasma and the sheath. Therefore, both of these simple and inexpensive, yet effective, methods can be applied across a wide range of experimental parameters in any ground-based RF plasma chamber to gain useful information regarding the sheath, which is needed for interpretation of dusty plasma experiments.
In this paper a method is described that allows mapping of the forces acting on dust particles in a GEC reference cell. Monodisperse particles are dropped into the plasma environment and their trajectories are tracked using a high-speed camera system to determine local accelerations and respective forces. Collecting data from a large number of particle drops allows the identification of three-dimensional vector fields for the acting forces. The procedure is described and multiple examples in which the method has been applied are given. These examples include a simple plasma sheath, plasmas perturbed by a horizontal and vertical dipole magnet, an array of multiple magnets mimicking the fields found at a lunar swirl, and the fields inside a glass box used for particle confinement. Further applicability in other plasma environments will be discussed shortly.
The Fourier-Kelvin Stellar Interferometer (FKSI) is a mission concept for a spacecraft-borne imaging and nulling interferometer for the near to mid-infrared spectral region. FKSI is a scientific and technological pathfinder to the Darwin and Terrestrial Planet Finder (TPF) missions and will be a high angular resolution system complementary to the James Webb Space Telescope (JWST). There are four key scientific issues the FKSI mission is designed to address. These are: 1.) characterization of the atmospheres of the known extra-solar giant planets, 2.) assay of the morphology of debris disks to look for resonant structures characteristic of the presence of extrasolar planets, 3.) study of circumstellar material around a variety of stellar types to better understand their evolutionary state, and in the case of young stellar systems, their planet forming potential, and 4.) measurement of detailed structures inside active galactic nuclei. We report results of simulation studies of the imaging capabilities of the FKSI, current progress on our nulling testbed, results from control system and residual jitter analysis, and selection of hollow waveguide fibers for wavefront cleanup.
Craspedodidymum nigroseptatum sp. nov. is described and illustrated based on specimens collected on decaying rachides of
Oncosperma horridum in Brunei Darussalam. It differs from other species of Craspedodidymum in producing dark brown conidia with
three to four thick, darkly-pigmented septa, and a paler basal cell. Conidia are broadly ellipsoidal to obovoid and truncate at the
base. Craspedodidymum nigroseptatum is compared with other species in the genus and a key to the genus is provided.
The development of more powerful and efficient aero-engines requires ways of increasing the torque transmitted by shafts, whilst also restricting their dimensions and weight. Thin-walled designs can assist this objective, but their use is limited by their torsional collapse behaviour. Of particular interest are conditions leading to buckling instability. The paper investigates the factors influencing this behaviour in order to provide the basis for an improved analysis method applicable to typical gas turbine aero-engine components.
The Riks finite element algorithm has been successfully applied to both plain shafts and shafts with holes. In the former case, it is shown that the perfect cylindrical geometry must be given an initial perturbation in order to give accurate predictions. The perturbation imposed is obtained by scaling the mode shape from an eigenvalue solution so that the maximum radial deformation is a percentage of the wall thickness. The predictions for both plain and holed shafts have been validated experimentally.
Eleven new intertidal fungi Aniptodera intermedia, Anthostomella nypae, Anthostomella nypensis, Anthostomella nypicola, Helicorhoidion
nypicola, Herpotrichia nypicola, Leptosphaeria nypicola, Lignincola nypae, Phomatospora nypicola, Trichocladium nypae, and Vibrissea nypicola
spp. nov., are described from Nypa fruticans. These new species are compared with existing species in the genera and illustrated with
interference light micrographs.
Byssosphaeria, Chaetosphaeria and Niesslia are discussed and illustrated in relation to their occurrence on palms. New collections of
B. schiedermayeriana are reported including Chaetosphaeria exima, which is a new synonym. Chaetosphaeria arecacensis, C. hongkongensis
and C. palmicola spp. nov. are described and new collections of C. callimorpha are reported. Cryptophiale is reported as a new
anamorph connection for Chaetosphaeria. Niesslia palmicola sp. nov. is described and new collections of N. exosporioides are recorded.
Ornatispora gen. nov. is introduced to accommodate several Chaetosphaeria-like species from palms. In Ornatispora, ascomata are
superficial, black, papillate, smooth-walled or covered in setae and paraphyses are filiform, non-septate and deliquesce in dried
material. Asci are 8-spored, clavate, and lack an apical apparatus and deliquesce at maturity, while ascospores are ellipsoidal,
1-septate, hyaline, verrucose and surrounded by a mucilaginous sheath. One species is closely associated with Didymostilbe
aurantiospora, which is considered to be the anamorph. Three new species of Ornatispora, and one new combination are described and
illustrated. Ornatispora is compared with Bertia, Chaetosphaeria, Peethambara and Niesslia.
Annulatascus species are common freshwater ascomycetes in the tropics. In this paper, the type species, Annulatascus velatisporus, and
a new species, A. triseptatus, are described and illustrated at light and electron microscope levels. Annulatascus triseptatus differs from
A. velatisporus in having three-septate ascospores surrounded by a thin sheath. The asci of both species have bilamellate ascus walls
and a bipartite apical ring. The upper part of the apical ring differentiates from the inner ascus wall layer and the lower part
elongates downwards during maturation. The mesosporium is the first formed ascospore wall layer followed by the episporium,
which is covered with verruculose ornamentations. The mucilaginous sheath of the ascospores is fibrillar or amorphous depending on
the fixation methods employed, and appears to be derived from the episporial verruculose ornamentations.
A new species of Menisporopsis was collected from submerged
wood in the Lam Tsuen River, Hong Kong. It differs from other
species in having conidia with 5–6-setulae. The generic concept of
Menisporopsis is briefly discussed and six species are accepted.
A
composite illustration of their conidial morphology is provided for comparison,
and a synopsis of and a key to the genus are
provided. The new species is described and illustrated with light and scanning
electron micrographs.
A taxonomic review and revision of the dematiaceous hyphomycete
genus Acrogenospora is presented. Species in this genus produce
acrogenous, solitary, nonseptate conidia from mononematous, simple conidiophores,
with multiple percurrent proliferations.
Acrogenospora altissima comb. nov. and A. megalospora
comb. nov. are proposed for the anamorphic states of two Farlowiella
species.
A. ovalia and A. subprolata spp. nov. are described from
submerged wood in Hong Kong. They differ from other Acrogenospora
species in shape, colour, and size of their conidia. A taxonomic key to
species in the genus is provided.
Stratiphoromyces brunneisporus gen. et sp. nov. occurring
on decaying petioles of Licuala spp., collected from rain forests
in Australia
and Brunei, is described and illustrated. It is unique in producing
a globose mass of brown, uniseptate, curved, setulate conidia, from
percurrently proliferating conidiogenous cells at the apex of solitary,
erect, unbranched, brown conidiophores. The genus is briefly
compared with Dictyochaeta and other similar hyphomycetes.
Results of an investigation into the fungi associated with submerged
wood in Lake Barrine, north Queensland, Australia are reported.
Thirty-nine fungi were identified, 15 ascomycetes, 23 deuteromycetes and
one
basidiomycete. The frequency of occurrence and the
effect of the incubation period on the recovery of fungi has also been
investigated
and is presented. The new species Massarina
lunispora and Dactylaria lakebarrinensis, and some other
notable species, are described and illustrated.
Aquaphila albicans gen. and sp. nov. from submerged wood
in the
tropics is described and illustrated. It produces hyaline,
multiseptate, fusoid or falcate conidia resembling the macroconidia of
Fusarium species, but differs by its conidiogenesis and the
aquatic habitat. The conidiophores of A. albicans are septate,
hyaline, sympodially proliferating with conidiogenous denticles.
Conidial development in A. albicans has been studied in culture
and
results are presented. The genus is compared with similar genera.
Gilmaniella bambusae sp. nov., from senescent culms of
Bambusa tuldoides in Hong Kong, is described and illustrated.
It differs from
other species of Gilmaniella in having small conidia and conidiogenous
cells with a verrucose wall. A key to and a synopsis of the
known species of Gilmaniella is provided.