An Emergence Trap for Aquatic Insects

Excerpt: The identification of organisms is a prerequisite to developing water quality criteria for aquatic life. Identification is necessary because differences in water quality requirements are specific and may be different for closely allied species. The taxonomy of various species, particularly those associated with the aquatic environment, is much more detailed and better known for adults than for immature instars. To facilitate correlation of adult and larval forms, a trap was needed to collect the emerging adults from the various streams

Modified bubble level senses pitch and roll angles over wide range

Bubble level sensor with fiber-optic field flattener is simple, rugged, small, and impervious to temperature and vibration effects. Pitch angles from -15 deg to +40 deg and roll angles of +30 deg are determined within 0.5 deg

Epitaxial Growth of an n-type Ferromagnetic Semiconductor CdCr2Se4 on GaAs(001) and GaP(001)

We report the epitaxial growth of CdCr2Se4, an n-type ferromagnetic semiconductor, on both GaAs and GaP(001) substrates, and describe the structural, magnetic and electronic properties. Magnetometry data confirm ferromagnetic order with a Curie temperature of 130 K, as in the bulk material. The magnetization exhibits hysteretic behavior with significant remanence, and an in-plane easy axis with a coercive field of ~125 Oe. Temperature dependent transport data show that the films are semiconducting in character and n-type as grown, with room temperature carrier concentrations of n ~ 1 x 10^18 cm-3.Comment: 12 pages, 3 figure

Innervation Patterns of Harp Seal (Pagophilus groenlandicus) Vibrissal Sensory Systems

Vibrissae, or whiskers, are largest among pinnipeds and are specialized hairs that potentially evolved to serve sensory, thermoregulatory or protective functions. Behavioral data from pinniped and rodent vibrissa studies indicate that functional differences exist between medial microvibrissae and lateral macrovibrissae. However, comparative data are lacking, and current pinniped studies only focus on the largest ventrolateral macrovibrissae. Consequently, we investigated the medial-to-lateral innervation and microanatomy of harp seal (Pagophilus groenlandicus) vibrissal Follicle-Sinus Complexes (F-SCs). F-SCs were sectioned either longitudinally or in cross-section. Sections remained unstained or were stained with a modified Bodian silver stain (innervation) or Masson’s trichrome stain (microanatomy). Harp seals possessed 88-105 F-SCs and each exhibited a tripartite blood organization system. Hair shafts were more circular medially but became more elliptical laterally. Medial F-SCs had more symmetrical dermal capsule thicknesses and distributions of major branches of the deep vibrissal nerve, but these symmetries diminished as F-SCs became more lateral. Medial-to-lateral axon counts ranged from 550 ± 97.4 axons/F-SC (medial) to 1632 ± 173.2 axons/F-SC (lateral). Overall, axon counts averaged 1221 ± 422.3 axons/F-SC (n=146 cross-sections), indicating a total of 117,235 axons/snout. Lateral F-SCs alone possessed a mean of 1533 ± 192.9 axons (n=82 cross-sections), which is similar to counts reported in other pinniped vibrissal innervation studies. These data suggest that conventional studies that only examine lateral vibrissae overestimate total innervation by ~20%. Moreover, we counted axon bundles with and without silver staining (n=834) and determined that unstained sections yielded more accurate and ~10% greater axon counts. Consequently, conventional analyses are likely only overestimating innervation by ~10% overall. The relationship between axon count and F-SC surface area was non-linear (p<<0.01; n=24 cross-sections), presumably from mechanoreceptors reaching carrying capacity, and axon densities were consistent across the snout. Presumptive Merkel-Neurite complexes and lanceolate endings were observed at the glassy membrane and outer root sheath interface. Our data agree well with behavioral research on pinnipeds and rodents that documents functional compartmentalization between micro-(medial) and macrovibrissae (lateral). Furthermore, our results support that vibrissal innervation variation observed among extant mammals initially diverged as a result of phylogeny and then environment (i.e., terrestrial, semi-aquatic, fully aquatic)

Comparison of cattail (Typha sp.) occurrence on a photo-interpreted map versus a satellite data map

A comparison between a 1985 photo-interpreted vegetation map and a vegetation map made from classified 1987 satellite data of the Loxahatchee National Wildlife Refuge showed that 81% of samples taken in areas occupied by cattail (Typha sp.) on the photo-interpreted map corresponded with cattail on the satellite data map.(5 page document

Oxidative gelation and functionality of wheat flour : effects of grain storage, flour aging, and grain type (hard or soft)

This study examined changes in flour functionality during storage of grain and subsequent aging of flour milled from the grain. Freshly harvested grain was stored for 24 weeks and flour milled from the grain at specified time intervals after harvest (0, 3, 6, 12, and 24 weeks). For each milling date flour functionality was measured on the day of milling (day 0) and at specified intervals after milling (1, 3, 6, 13, 27, and 62 days). Storage and aging were conducted at 23 ± 1°C. The functional properties examined were flour absorption characteristics, quantified using the solvent retention capacity (SRC) test, and oxidative gelation capacity (OGC), which was measured viscometrically, using a Rapid Visco Analyzer (RVA). SRC measures absorption capacity of flour emphasizing different flour polymers in each of the four solvents (water, all polymers: sucrose, arabinoxylans (AX) and gliadins: sodium carbonate, damaged starch: lactic acid, glutenins). Oxidative gelation is a process whereupon a weak gel is formed in a hydrated flour system under oxidative conditions and is thought to be largely a function of the reactivity of ferulic acid residues esterified to AX, although proteins are also involved. To determine if oxidation of flour lipids might accompany changes in OGC, the concentration of malondialdehyde (MDA), a lipid oxidation byproduct, was measured. Four soft-wheat varieties with divergent functionalities were selected to examine the effects of storage and aging. Additionally, a survey was conducted to examine the range of OGC in a selection of hard-grained wheat varieties from the Oregon State University wheat-breeding program. From this survey, one variety with high and one variety with low OGC were selected for a pilot study to determine the effect of hydrogen peroxide and azodicarbonamide (ADA) concentrations on OGC in straight grade flour. Variety was the strongest factor in determining flour functionality expressed as SRC and OGC. This is unsurprising, because varieties were chosen based on differences in absorption characteristics and OGC as indicated by preliminary testing. In contrast, variety was the weakest factor in determining changes in MDA concentration. As a function of grain storage time, water, sucrose and sodium carbonate SRC values increased. In contrast, lactic acid SRC values declined. Although many of these changes were statistically significant, their functional significance remains unclear. As a function of grain storage time, OGC initially increased to week 3 then declined to week 24. Not only was this change statistically significant, but the magnitude of the change could be considered functionally significant. Because OGC is a trait that currently only has theoretical value in food processing (i.e. OGC is not a trait currently taken into consideration during food processing), it is difficult to definitively conclude what constitutes functional significance. Grain storage time had the strongest influence on changes in MDA concentration. The trend of changes in MDA concentration was similar to that observed for OGC. Flour age was the weakest contributor to changes in SRC. Looking at individual SRC solvents, flour aging time did not significantly influence changes in water SRC values. However, as flour aged, sucrose SRC values significantly increased and sodium carbonate and lactic acid SRC values decreased. Although changes in sucrose, sodium carbonate, and lactic acid SRCs were statistically significant, their functional significance was again unclear. As a function of flour age, OGC increased. As a function of flour age, MDA concentration initially increased, but subsequently declined and remained constant from day 6 to day 62. Each variety appeared to show a different relationship between peroxide peak viscosity (PPV) and peroxide peak breakdown viscosity (PPBV). Proportional PPBV also appeared to differ between varieties, and the relationships (PPBV% vs PPV) were nonlinear. This suggested that there was a maximum PPV for each variety at which PPBV no longer increased. Data suggest qualitative differences in the gels formed in each variety that require further investigation. Speculation allows the idea that the RVA method used here could provide a way of expressing functional differences in OGC that might relate to structure differences in AX

The relationship between biophysical variables and halocarbon distributions in the waters of the Amundsen and Ross Seas, Antarctica

Little is known regarding the distribution of volatile halogenated organic compounds (halocarbons) in Antarctic waters and their relation to biophysical variables. During the austral summer (December to January) in 2007-08 halocarbon and pigment concentrations were measured in the Amundsen (100-130 degrees W) and Ross Sea (158 degrees W-160 degrees E). In addition, halocarbons were determined in air, snow and sea ice. The distribution of halocarbons was influenced to a large extent by sea ice, and to a much lesser extent by pelagic biota. Concentrations of naturally produced halocarbons were elevated in the surface mixed layer in ice covered areas compared to open waters in polynyas and in the bottom waters of the Ross Sea. Higher concentrations of halocarbons were also found in sea ice brine compared to the surface waters. Incubations of snow revealed an additional source of halocarbons. The distribution of halocarbons also varied considerably between the Amundsen and Ross Seas, mainly due to the different oceanographic settings. For iodinated compounds, weak correlations were found with the presence of pigments indicative of Phaeocystis, mainly in the Ross Sea. Surface waters of the Amundsen and Ross Seas are a sink for bromoform (saturation anomalies, SA, -83 to 11%), whereas sea ice was found to be both a source and sink (SA -61-97%). In contrast, both surface waters and sea ice were found to be a source of chloroiodomethane (SA -6-1 200% and 91-22 000 resp.). Consequently, polar waters can have a substantial impact on global halocarbon budgets and need to be included in large-scale assessments. (C) 2012 Elsevier B.V. All rights reserved