Abstract One of the challenges for bryozoans is to avoid refiltering water that has already had its plankton removed. Larger colonies develop colony-wide maculae-centered feeding currents and generally have elevated maculae (monticules). We hypothesize height density spacing monticules are inversely proportional curvature colony surface. Larger, flatter should higher more closely spaced monticules. compare two Permian stenolaemate whose form branches with elliptical cross sections: smaller...

Synthetic pyrethroids are lipophilic insecticides whose biological activity seems to be directly related their chemical structure. In this investigation differences in cutaneous sensation were detected by human participants between synthetic with a cyano group the (S)-configuration of 3-phenoxybenzyl alcohol molecular structure (fenvalerate) and those that do not (permethrin). A strong relation was noted insecticidal potency degree induced for alpha-cyano non-cyano pyrethroids, prominent...

Abstract In searching for sources of fibers ubiquitous to our everyday environment and respirable size, the authors examined 22 talcum products commonly available on retail shelves found fiber contents ranging from 8 30% by count, with an average 19%. Fibrous particulates were generally under 1.0 μ in diameter lengths 1.5 6.0 μ. From 0.3 3.0% quartz was 21 samples remaining sample had 54.4% quartz. The also analyzed metals; four exceptions, levels cobalt, nickel, chromium manganese low....

Abstract Investigations have been conducted in fibrous glass plants to assess the prevalence and significance of work-related dermatitis. Fibrous can cause skin irritation most people. This is usually transient. Persons with dermographism are more likely be intolerant this discomfort. Allergy does not play a role Methods control plant home presented.

The allergic reaction in industry of most interest to the dermatologist is contact dermatitis, which accounts for 20% or less all occupationally incurred dermatitis. Other forms industrial allergy are uncommon rare, but may also see some cases bronchial asthma and urticaria caused by certain agents occupational environment. This review allergens designed furnish broader knowledge multiple potentialities emphasize need consider a more complete toxicologic picture an exposure. list...

This study examines the barnacle symbionts on 168 blue crabs, Callinectes sapidus, taken from both shallow and deep estuarine environments in area of Beaufort, North Carolina. The purpose was to quantify prevalence, intensity, abundance, spatial distribution ectosymbiotic Chelonibia patula crabs. proportion crabs fouled 67%. There no difference prevalence barnacles versus environment. Results indicate female were significantly more than males. suggests that intensity are dominantly...

Abstract Although improvements in formulations of cutting and grinding fluids have been made, occupational dermatitis can still be a problem. Oil acne folliculitis are the most common cutaneous problems those who work with insoluble oils. Bacteria lubricating coolants may contribute to breakdown coolant but unrelated outbreaks folliculitis. The chief problem which results from exposure soluble oils synthetic is eczematous contact dermatitis, disease multiple causation. These two important...

The evolution of borings has shown that the morphology is a function both borer and its substrate. This study investigated effect bryozoan internal skeletal on dimensions distribution borings. One hundred forty-three trepostome colonies from Middle Upper Ordovician strata northern Estonia were examined. Of these, 80% matrix entombed, longitudinally sectioned ramose hemispherical colonies, 20% matrix-free allowed examination colony surfaces. Seventy-one percent bored, whereas 88% bored. On...

The long-lived (about 20 yr) bryozoan Adeonellopsis sp. from Doubtful Sound, New Zealand, precipitates aragonite in isotopic equilibrium with seawater, exerting no metabolic or kinetic effects. Oxygen isotope ratios (δ 18 O) 61 subsamples (along three branches of a single unaltered colony) range −0.09 to +0.68‰ PDB (mean = +0.36‰ PDB). Carbon 13 C) +0.84 +2.18‰ +1.69‰ Typical cool-water carbonates, δ O-derived water temperatures 14.2 17.5 °C. has minimum temperature growth threshold 14 °C,...

Synopsis This study focuses on bryozoans from the Upper Ordovician rocks of Montagne de Noire, southern France and additional material contemporary Carnic Alps. Based museum collections, 68 bryozoan species were identified with 18 being new: Ceramo‐porella grandis sp. nov., Crassalina fungiforme Lichenalia nodata Atactoporella magnopora Dekayia buttleri Stigmatella carnica Trematopora gracile Bythopora tenuis Nicholsonella divulgata N. recta Matsutrypa elegantula M. rogeri Nematotrypa...

Commensal epizoozoans and episkeletozoans are rarely preserved attached to the external exoskeleton of Late Ordovician trilobite Flexicalymene. Of nearly 15,000 Flexicalymene specimens examined, 0.1% show or episkeletozoans. Factors limiting fouling include a shallow burrowing life style, frequent molting host, larval preference for other substrates, observational bias caused by overlooking small organisms, loss non-calcified, outermost cuticle prior fossilization as weathers from encasing...

Spatiopora Ulrich, 1882 is a trepostome bryozoan that found encrusting living orthoconic nautiloids in the Upper Ordovician (Katian) of North America, as do several other bryozoans. These epizoozoan bryozoans are characterized by possessing thin unilaminate zoaria with rows elongate maculae, which may be monticulate and aligned coaxially to host growth axis. develop distinctive linear shape response growing on conical host, rather than channelized water flow along host. Monticules increase...

Abstract:  Quantifying the effects of ocean acidification requires understanding skeletal carbonate mineralogy in living marine organisms. X-ray diffractometry (XRD) is simplest and most commonly used technique for determining this. Samples being analyzed by XRD are typically pretreated to remove organic material prior grinding a crystallite powder. This pretreatment was traditionally performed as may obscure mineral peaks on traces. study compared controls with no common methods: roasting,...

Stable oxygen and carbon isotope ratios are one of the most accurate ways determining environmental changes in past, which used to predict future change. Biogenic carbonates from marine organisms common source samples for stable analysis. Before they analyzed by mass spectrometry, any organic material is traditionally removed three pretreatment methods: roasting, bleaching, or with hydrogen peroxide at various strengths durations.This study compares δ18 O δ13 C values a control no those five...