Miracle-dz/UniFAR-FTUs huggingface dataset:
Dissolved Organic Matter as Food for Black Fly Larvae (Diptera:Simuliidae)

Black fly larvae occur in many lotic habitats but often dominate the benthos of lake-outlet and brownwater (humic) stream communities. Water in these habitats contains abundant dissolved organic material (DOM). Amorphous material commonly found on black fly labral fans was formerly but erroneously thought to be an endogenously produced glycoconjugate that aided particle capture. We hypothesized that architecture of the labral fans may cause in situ flocculation of DOM, which is then directly ingested. Half-grown Simulium vittatum Zetterstedt and S. piperi Dyer & Shannon larvae were held for 84 h in stir-bar-driven rearing chambers containing filtered water with or without 3.0 mg/L brewer's yeast and with or without 20.0 mg/L DOM (an aqueous extract of moss). Water was partially replaced every 6 h. Scanning electron microscopy (SEM) was used to examine particulate material from test water collected on membrane filters and to study labral fans of selected larvae from parallel experiments. Other larvae were longitudinally sectioned and stained with Alcian Blue, which detects glycoconjugates. Concentrations of DOM (determined by ultraviolet spectroscopy) and fine particulate organic matter (measured by filtration) in chambers did not change over 84 h. Larvae in control and DOM-only trials displayed aggregative behavior typical of severely food-limited simuliids, whereas larvae in yeast-supplemented trials were haphazardly arranged. Control larvae exhibited little or no growth (increase in mean body length). Larvae in both DOM and yeast-supplemented treatments grew significantly more than control larvae, achieving growth rates of 4.0-17.0%/d (DOM-only), 11.3-14.8%/d (yeast-only), or more. Guts of larvae from all treatments stained positively, indicating that they contained glycoconjugates. Filters and labral fans examined by SEM contained yeast cells but not bacterial cells. However, labral fans also lacked evidence of adhering glycoconjugates. Small quantities of amorphous material consistent with flocculated DOM were observed on filters. Simuliid larvae can grow in a medium containing only allochthonously derived DOM. Although evidence is inconclusive, we speculate that DOM is precipitated on labral fans and ingested. Under natural conditions, DOM may be a direct and significant food source for simuliid larvae.
Exotic earthworm distribution in a mixed-use northern temperate forest region: influence of disturbance type, development age, and soils

The impacts of invasive earthworms in northern North American forests include mixing of soil and litter horizons, changes to nutrient availability, and shifts in understory plant communities. Multi-use forests, with concomitant commercial logging and recreational activities, may have high rates of earthworm dispersal from human activities. Here, we investigated if soil physical and chemical properties, in addition to disturbance type, influence the success of earthworm establishment. We characterized the distribution of earthworms in a multi-use forested area in the Great Lakes St. Lawrence forest region of central Ontario and related earthworm presence and community structure to human influences (i.e., disturbance type, age of development) and edaphic properties. Although soil texture correlated significantly with Lumbricus populations, the influence of edaphic properties was small compared with disturbance type and history. Fishing and camp sites were dominated by Lumbricus, while gravelled roads had hi.
Measuring phenological variability from satellite imagery

Vegetation phenological phenomena are closely related to seasonal dynamics of the lower atmosphere and are therefore important elements in global models and vegetation monitoring. Normalized difference vegetation index (NDVI) data derived from the National Oceanic and Atmospheric Administration's Advanced Very High Resolution Radiom- eter (AVHRR) satellite sensor offer a means of efficiently and objectively evaluating phenological characteristics over large areas. Twelve metrics linked to key phenological events were computed based on time-series NDVI data collected from 1989 to 1992 over the conterminous United States. These measures include the onset of greenness, time of peak NDVI, maximum NDVI, rate of greenup, rate of senescence, and integrated NDVI. Measures of central tendency and variabil- ity of the measures were computed and analyzed for various land cover types. Results from the analysis showed strong coincidence between the satellite-derived metrics and pre- dicted phenological characteristics. In particular, the metrics identified interannual variability of spring wheat in North Dakota, characterized the phenology of four types of grasslands, and established the phenological consistency of deciduous and coniferous forests. These results have implications for large- area land cover mapping and monitoring. The utility of re- motely sensed data as input to vegetation mapping is demon- strated by showing the distinct phenology of several land cover types. More stable information contained in ancillary data should be incorporated into the mapping process, particu- larly in areas with high phenological variability. In a regional or global monitoring system, an increase in variability in a region may serve as a signal to perform more detailed land cover analysis with higher resolution imagery.
Growth Modulation during Juvenile Rearing Can Reduce Rates of Residualism in the Progeny of Wild Steelhead Broodstock

Abstract Residualism is the failure of some hatchery-reared salmonid juveniles to out-migrate as smolts with the rest of their cohort. We released hatchery-reared juveniles from domesticated- and wild-origin broodstock steelhead and measured their relative rates of residualism. The residualism rate exhibited by the offspring of wild broodstock was more than one order of magnitude greater than that of domesticated stock. Further, we experimentally manipulated the growth trajectories of juvenile offspring of wild broodstock to decrease the size variance among released fish. Our expectation was that fewer fish would be too small or too large to smolt as yearlings. Small fish placed on an aggressive rearing regimen (reared separately from larger fish, fed more food more often) residualized at a lower rate than did comparable control fish (reared with large fish without supplemental feeding). We saw no effect of a lower feeding regimen on the residualism rate of large fish, but the lower feeding regimen did no.
Temperature reaction norms of Daphnia carinata fitness: the effects of food concentration, population density, and photoperiod

Increasing concerns over climate change have renewed interest in temperature effects on aquatic organisms. The effects of temperature, food concentration, population density, and photoperiod on Daphnia carinata fitness were examined using life-table experiments in a full factorial design. The high temperature enhanced fitness at the high food concentration, but depressed it at the low food concentration. The temperature–food interactions were significant in the four combinations of two population densities and two photoperiods. The temperature–population density interactions were significant in the two combinations of two photoperiods and the high food concentration, in which the high population density masked the temperature effects. The temperature–photoperiod interaction was only significant in one combination with the low population density and the low food concentration, in which the long day length weakened the temperature effects. Such complicated interactions suggest that multiple ecological variables need to be taken into account simultaneously when assessing temperature effects on zooplankton in nature.
Auxiliary β Subunits Differentially Determine PKA Utilization of Distinct Regulatory Sites on CaV1.3 L-Type Ca2+ Channels

L-type calcium channels (CaV1.1–CaV1.4) link Ca2+ influx to membrane depolarization and serve a critical role in regulating membrane excitability, muscle contraction, hormone secretion, and gene transcription. In many tissues, L-type calcium channel activity (CaV1.1 and CaV1.2) is enhanced by transmitters and hormones that activate the cAMP-dependent protein kinase (PKA), which is largely thought to be mediated via phosphorylation of the pore forming α subunit. However, the ability of PKA to regulate CaV1.3 and the sites contributing to effective modulation of channel activity remains to be established. Using HEK 293 cells, we demonstrate that currents carried by the long C-terminal splice variant of CaV1.3 (CaV1.3L) are selectively enhanced compared to the short C-terminal splice variant (CaV1.3S) when the catalytic subunit of PKA is introduced into the cell via the whole-cell recording electrode. However, the persistence of this regulation is dependent on the identity of the auxiliary β subunit, such that PKA produces only a transient increase in the presence of β3 while a persistent increase is observed in the presence of the β2a subunit. Site-directed mutagenesis of consensus PKA phosphorylation sites revealed that Ser1964 and Ser1743 in CaV1.3L were the predominant sites controlling PKA modulation in the presence of the β3 and β2a auxiliary subunits, respectively. Therefore, β subunits determine the contribution of distinct sites within CaV1.3 towards PKA-mediated enhancement of channel activity. These data suggest that auxiliary β subunits govern the access of signaling enzymes to L-type calcium channels.
The status and habitat of Spotted Crakes Porzana porzana in Britain in 1999

Capsule The first Britain-wide survey of Spotted Crakes Porzana porzana undertaken in 1999 recorded 73 singing males mostly in wet herb habitats with peak records in May. Aims To provide baseline information on the number and distribution of breeding Spotted Crakes and a description of their preferred habitat in Britain. Methods Volunteers and site wardens/managers visited sites at which Spotted Crakes had been recorded 1988–98. High priority sites were visited once a week during May and June (at least eight visits), while remaining sites each received three visits. General habitat data were collected, both from an area of 5 m × 5 m surrounding the Spotted Crake singing locations and from ten randomly selected 5 m × 5 m squares within sites. Results Seventy-three singing male Spotted Crakes were recorded at 29 sites in England, Wales and Scotland during May and June. Seven additional singing males were recorded outside the survey period, and at three sites juveniles were seen yet no song was heard. Records peaked in May, although Spotted Crakes sang later in the north. At the landscape level, singing Spotted Crakes were characterized by dominant wet herb species, 35% standing water (4.5–17.3 cm deep) and tall (>70 cm) vegetation. Within sites, Spotted Crake chose more mosaic vegetation, characterized by wet grass species, greater water cover and shorter vegetation. Conclusion Spotted crakes are more than a sporadic breeding visitor to Britain, but better monitoring is required to understand the population trends. A basic insight into habitat preferences provides a starting point for further studies.
Altered locomotory behavior in woodlice (Oniscus asellus (L.)) collected at a polluted site

The locomotory behavior of woodlice (Oniscus asellus (L.)) collected along a gradient of pollution from a plastics fire was quantified automatically for 4 h in the laboratory employing computer‐aided video tracking. Six locomotory parameters were measured and the corresponding individual body metal concentrations determined. Additional woodlice were collected from the same site for total protein and glycogen analyses. Woodlice collected from the litter layer overlying a pyrolyzed plastic layer spent significantly less time in activity, resulting in a walked distance less than 50% of that of woodlice collected from a nearby reference location. Furthermore, a tendency to turn predominantly in either a left or a right direction and a tendency toward a higher discontinuity in moving was found for the woodlice collected on the pyrolyzed plastic. Overall, the aberrant behavior coincided with significantly elevated body concentrations of heavy metals and lowered protein and glycogen levels. The interference of metals with neurological and metabolic processes is discussed in relation to locomotion.
Divergence time estimations and contrasting patterns of genetic diversity between Antarctic and southern South America benthic invertebrates

La diversidad, abundancia y composicion de grupos taxonomicos en el oceano Austral difiere de otros lugares del planeta debido a que su biogeografia refleja la compleja interaccion de la tectonica, oceanografia, clima y elementos biologicos desde el Eoceno. Algunos grupos de organismos marinos bentonicos muestran altos niveles de divergencia genetica entre provincias de esta region, apoyando la existencia de procesos vicariantes por tectonica de placas mientras que otros grupos, con alta capacidad dispersiva, muestran procesos de divergencia mas recientes. Mas aun, el reciente descubrimiento de larvas de decapodos no Antarticos en peninsula Antartica sugiere que algunos grupos podrian cruzar la Corriente Circumpolar Antartica. Se analizaron los niveles de divergencia genetica en especies congenericas en invertebrados bentonicos del Oceano Austral con potencial dispersivo. Para esto, se incluyo en los analisis secuencias del gen COI de un equinoideo (Sterechinus), un gastropodo (Nacella), y un bivalvo (Yoldia). Considerando los niveles de diferenciacion genetica y asumiendo la Hipotesis del Reloj Molecular, estimamos la separacion entre grupos de ambos continentes. Tambien comparamos los niveles de variacion genetica entre especies antarticas y subantarticas de Nacella y Sterechinus para determinar el efecto de los episodios glaciales del Cuaternario en su demografia. Detectamos claras diferencias geneticas entre especies congenericas antarticas y subantarticas de Sterechinus, Nacella y Yoldia. La instalacion de una barrera efectiva entre antartica y subantartica ocurrio casi al unisono (3.7 a 5.0 Ma) para estos grupos de organismos, y muy posterior a la separacion fisica de ambos continentes. Comparaciones geneticas entre especies antarticas y subantarticas detectaron menores niveles de diversidad genetica en especies antarticas sugiriendo un efecto mas pronunciado de los episodios glaciales en Antartica que en Sudamerica. Estos resultados podrian reflejar el dramatico efecto de los ciclos glaciales del Cuaternario en los tamanos poblacionales antarticos, especialmente en grupos con rangos batimetricos estrechos. El presente estudio provee nueva evidencia de los procesos de diferenciacion entre organismos antarticos y sudamericanos. Ninguno de los generos analizados mostro evidencia de flujo genico recurrente a traves de la Corriente Circumpolar Antartica desde el Mio-Plioceno. Las comparaciones geneticas indican que especies antarticas y subantarticas fueron diferencialmente afectadas por los periodos glaciales.
Perforative Corrosion of Pyrite Enhanced by Direct Attachment of Acidithiobacillus ferrooxidans

This study aimed to determine the relationship between cell adhesion and pyrite corrosion. In order to determine cell adhesion rates, a new in vivo imaging procedure was developed with CLSM. Total bacteria coverage rates remained low (< 14%). Adsorption isotherms pointed out two types of cell adhesion sites. Bacteria adhered mainly to corrosion pittings walls with a higher affinity. They favour the formation of deep corrosion pits by maintaining short-range electronic circulations and they avoid surface passivation. This study completes the common model of bio-corrosion of pyrite and we propose to refine the direct/indirect model by proximal and distal approaches.
Informal Writing Instruction and Dramatic Play to Support Kindergarten Children’s Language and Writing Development

This paper describes children’s and their teacher’s interactions in a northern Alberta kindergarten class where the teacher took up a role as a kindergarten student learning to write, as well as roles in dramatic play that allowed her to introduce authentic use of texts. In these informal writing instructional contexts, the teacher used verbal and nonverbal modes to communicate about text creation and directed children’s behaviour, as has been found in studies of formal writing instruction. However, she also used language for affiliative purposes and created space for children to engage in frequent communication using verbal and nonverbal modes. The children created a wide range of texts, some using scribbles and drawing to communicate meaning and others using print and drawing.
Compared to them, we are angels: Parliament, othering and the fight against corruption in Ghana

Due to its supervisory responsibility over the executive and public institutions, including ministries, departments and agencies (MDAs), Ghana’s legislature has a mandate to check and fight corruption and make its practice a high risk, low-gain activity. The commitment, urgency and the willingness to fight corruption can be seen not only in creating the legislative framework for addressing corruption, promoting governmental accountability and acting as a check on the executive, but also in how the subject of corruption is broached in parliamentary debates and discussions, an area which relatively lacks scholarly attention. First, using an interpretive content analysis, this paper studies the approaches to the fight against corruption in Ghana by examining the Parliamentary Committee report on the National Anti-Corruption Action Plan (NACAP) and, the debate thereof, in order to uncover the focus of the NACAP. Second, the paper examines Parliamentarians’ use of evaluative language in parliamentary debates to enact otherness and how this othering affects the fight against corruption in Ghana. The paper finds that the NACAP suggests a three-pronged approach to the fight against corruption, viz: ethical/educational, multi-stakeholder and legal approaches. However, the implementation of these approaches has been ineffective due to certain Ghanaian cultural practices. Again, the paper finds that as a result of othering between government and opposition MPs, the fight against corruption is only incidental in parliamentary debates, indicating a low parliamentary commitment to the fight against corruption. Thus, the paper suggests that the fight against corruption must be taken away from the corridors of the Parliament of Ghana.
EFFECTS OF BROMIDE AND IODIDE ON STALK SECRETION IN THE BIOFOULING DIATOM ACHNANTHES LONGIPES (BACILLARIOPHYCEAE) 1

Extracellular polymeric substance (EPS) secretion was examined in the stalked marine diatom Achnanthes longipes Ag. in defined medium. This common biofouling diatom exhibited an absolute requirement for bromide for stalk production and substratum attachment, whereas elevated iodide concentrations in the growth medium inhibited stalk formation and adhesion. Varying EPS morphologtes resulted from altering bromide and iodide levels: pads, stalk‐pads, stalks, and no EPS. Cells showed no differences in growth with bromide or iodide concentrations, indicating that they were not physiologically stressed under conditions that impaired EPS secretion. Cells grown in elevated iodide secreted significantly more soluble extracellular carbohydrate into the medium, suggesting that the EPS was soluble and unable to be polymerized into a morphologically distinct gel. By replacing sulfate with methionine, the diatom lost its ability to form stalks even in the presence of bromide, indicating that free sulphate may be required for proper cross‐linking of stalk polymers. Lotus‐FITC, a fluorescent‐tagged lectin, preferentially labeled the EPS and, thus, was used to visualize and quantify EPS secretion along a bromide gradient in conjunction with an image analysis system. This technique demonstrated a direct correlation between the amount of bromide present in the medium and the specific EPS morphology formed.
Validation of the alkalinity anomaly technique for investigating calcification of photosynthesis in coral reef communities

Experiments were conducted to establish the validity of the alkalinity anomaly technique for investigating rates of calcification and photosynthesis by coral reef-building organisms. Rates of CaCO3 precipitation by whole colonies of the scleractinian coral Pocillopora damicornis (L.) were estimated under light and dark conditions with two different methods: complexometric titration of Ca with EGTA and acid titration of total alkalinity, with and without correction for alterations in the concentrations of ions other than carbonate species. The two techniques provided equivalent estimates of light-enhanced and dark calcification, irrespective of whether corrections were applied to the total alkalinity data for changes in nutrient concentration. These results confirm that the assumptions of the alkalinity anomaly technique are fundamentally correct and that it is not necessary to correct total alkalinity data for changes in nutrient concentration because the corrections which apply are smaller than the variability observed in calcification data.
An Efficient Smolt Trap for Sandy and Debris-Laden Streams

Abstract Tripod weir and box traps are traditionally used to capture and enumerate out-migrating salmonid smolts in short-term studies and in streams where temporary or portable traps are the only practical option. Although traditional traps can be effective when conditions are ideal, they are often unable to withstand high-discharge events in streams containing a large amount of debris or sandy substrates. We created a rotary-screw trap and resistance board weir hybrid design that we evaluated along with a tripod weir and box trap, both in a 6.1-m-wide flume and in the field. The new design outperformed the tripod weir in both situations. The tripod weir failed in 10 min in the flume trial, whereas the new design was still operating at the conclusion of an 8-h trial under the same conditions. The new design operated continuously in the field during a high-discharge event that caused the tripod weir to fail. The new design also required less frequent cleaning than the tripod weir. The trap efficiency of t.
Protease inhibitors of pigeonpea (Cajanus cajan) and its wild relatives

Plant protease inhibitors have been implicated in defense against insect pests. Podborer and pod fly are major pests of developing seeds of pigeonpea (Cajanus cajan L. Millsp.). Therefore, we studied the presence of protease inhibitors in seeds of pigeonpea and its wild relatives. Seed extracts were analyzed for protease inhibitor activities by caseinolytic assay, and the number of protease inhibitors determined by polyacrylamide gel electrophoresis. Besides trypsin and chymotrypsin inhibitors, seed extracts contained weak papain inhibitor(s) but no bromelain inhibitor. Treatment of seed extract with bromelain generated new active forms of trypsin inhibitors. The relative amounts of different trypsin inhibitors and the total trypsin inhibitor activity varied with different extraction media. Trypsin inhibitors were not detectable in pigeonpea leaves. The profiles of trypsin and chymotrypsin inhibitors in almost all the cultivars of pigeonpea analyzed were similar; however, those in wild relatives were quite variable.