Miracle-dz/UniFAR-FTUs huggingface dataset:
Survival, Growth, and Reproduction Responses in a Three‐Generation Exposure of the Zebrafish (Danio rerio) to Perfluorooctane Sulfonate

A prior multigenerational perfluorooctane sulfonic acid (PFOS) exposure investigation in zebrafish reported adverse effects at 0.734 µg/L, among the lowest aquatic effect levels for PFOS reported to date. The present three‐generation PFOS exposure quantified survival, growth, reproduction, and vitellogenin (VTG; egg yolk protein) responses in zebrafish, incorporating experimental design and procedural improvements relative to the earlier study. Exposures targeting 0.1, 0.6, 3.2, 20, and 100 µg/L in parental (P) and first filial (F1) generations lasted for 180 days post fertilization (dpf) and the second filial generation (F2) through 16 dpf. Survival decreased significantly in P and F2 generation exposures, but not in F1, at the highest PFOS treatment (100 µg/L nominal, 94–205 µg/L, measured). Significant adverse effects on body weight and length were infrequent, of low magnitude, and occurred predominantly at the highest exposure treatment. Finally, PFOS had no significant effects on P or F1 egg production and survival or whole‐body VTG levels in P or F1 male fish. Overall, the predominance and magnitude of adverse PFOS effects at <1 µg/L reported in prior research were largely nonrepeatable in the present study. In contrast, the present study indicated a threshold for ecologically relevant adverse effects in zebrafish at 117 µg/L (SE 8 µg/L, n = 10) for survival and 47 µg/L (SE 11 µg/L, n = 19) for all statistically significant negative effects observed. Environ Toxicol Chem 2024;43:115–131. © 2023 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.
Gas-breakthrough pressure of FEBEX bentonite

Abstract The gas-breakthrough pressure values in saturated FEBEX bentonite were determined for different dry densities and sample sizes. They increased clearly with dry density and were always higher than the swelling pressure of the bentonite. In high-density samples, gas flow tended to stop abruptly after breakthrough, whereas, in lower density samples, gas flow decreased gradually until a given pressure gradient was reached. The permeabilities computed after breakthrough (which usually did not stabilize) were inversely related to dry density. This would indicate that, despite the fact that flow took place through preferential pathways, the bentonite matrix and its swelling conditioned the ease of pathway formation. These paths sometimes closed quickly after breakthrough and others remained open, allowing a gradual decrease in gas flow. After resaturation of the bentonite, the same breakthrough pressures and permeabilities were found, pointing to the perfect healing of these preferential pathways. A sealed interface along the bentonite did not seem to affect the breakthrough pressure or permeability values.
MICROCLIMATE STUDY OF KARTCHNER CAVERNS, ARIZONA

A detailed two-year study of the microclimate in Kartchner Caverns determined that the most significant problem in maintaining the microclimate of the cave is the potential for drying out due to increased airflow. Two factors—a small, hypothesized upper second entrance and a slight geothermal warming of the cave—control natural airflow and increase the amount and intensity of winter air exchange. The average amount of water reaching the cave is 7.9 mm/yr, only twice the amount lost by evaporation from cave surfaces. Kartchner Caverns has an average relative humidity (RH) of 99.4%. Useful measurement of RH required a dewpoint soil psychrometer rather than a sling psychrometer. Moisture loss from cave surfaces is proportional to relative humidity, and small changes in RH have a dramatic effect on evaporation from cave surfaces. A lowering of RH to 98.7% would double the evaporation rate and start to dry out the cave. The volume of air exchange in the cave was estimated from direct measurement, changes in CO 2 concentration, and temperature profile models. All of these methods are consistent with a volume of 4,000 m³/day entering the cave during the winter. During the summer, the direction of airflow reverses and the volume of air leaving the cave is much smaller than during the winter months. Surface air is almost always drier than cave air—only during the summer months when rain occurs does outside air contain more moisture. However, the rate of air exchange is greatly reduced during the summer, which minimizes any potential effect of increased outside moisture. Radon concentrations in the cave are high enough to be of concern for long-time employees but not for the general public. Radon 222 concentrations average 90 pCi/L and radon daughters average 0.77 Working Levels (WL) in the main part of the cave. During the winter, radon levels in the Echo Passage are up to six times higher than the rest of the cave due to the passage’s stable microclimate and limited air movement, which greatly reduces radon removal by plateout. Natural removal by ventilation is only a minor factor in determining radon levels in the rest of the cave.
On the early history of the wild reindeer (Rangifer tarandus L.) in Finland

This paper discusses the early migration of the wild reindeer into Finland. Reindeer bones found in dated archaeological contexts suggest that the two subspecies, the mountain reindeer (Rangifer tarandus tarandus L.) and the forest reindeer (Rangifer tarandus fennicus Lönnb.), were part of our fauna as early as c. 9000 BP and 7000 BP, respectively. The mountain reindeer may be descended from the European Pleistocene reindeer, and may have migrated into northern Finland via the west coast of Norway. The forest reindeer invaded Finland directly from the east, from its glacial refugia in Siberia. During the Holocene, the distribution ranges of these two subspecies fluctuated in accordance with climatic and vegetational changes in northern Finland.
Using transcranial direct-current stimulation (tDCS) to understand cognitive processing

Background—Recent theoretical models of schizophrenia posit that dysfunction of the neural mechanisms subserving predictive coding contributes to symptoms and cognitive deficits, and this dysfunction is further posited to result from N-Methyl D-aspartate glutamate receptor (NMDAR) hypofunction. Previously, by examining auditory cortical responses to self-generated speech sounds, we demonstrated that predictive coding during vocalization is disrupted in schizophrenia. In order to test the hypothesized contribution of NMDAR hypofunction to this disruption, we examined the effects of the NMDAR antagonist, ketamine, on predictive coding during vocalization in healthy volunteers and compared them to the effects of schizophrenia. Methods—In two separate studies, the N1 component of the event-related potential (ERP) elicited by speech sounds during vocalization (Talk) and passive playback (Listen) were compared to assess the degree of N1 suppression during vocalization, a putative measure of auditory predictive coding. In the cross-over study, 31 healthy volunteers completed two randomly ordered test days, a saline day and a ketamine day. ERPs during the Talk/Listen task were obtained preinfusion and during infusion on both days, and N1 amplitudes were compared across days. In the case-control study, N1 amplitudes from 34 schizophrenia patients and 33 healthy controls were compared. Results—N1 suppression to self-produced vocalizations was significantly and similarly diminished by ketamine (Cohen's d=1.14) and schizophrenia (Cohen's d=.85). Conclusions—Disruption of NMDARs causes dysfunction in predictive coding during vocalization in a manner similar to the dysfunction observed in schizophrenia patients, consistent with the theorized contribution of NMDAR hypofunction to predictive coding deficits in schizophrenia.
The Use of Stable Isotopes in Studies of Nutrient Cycling: Carbon Isotope Composition of Amazon Varzea Sediments

In order to characterize the organic and isotopic compositions and the origin of the sediment deposited in the Amazon river floodplain, samples from lake bottom, grass cover, and vegetation free sediments were studied. The results obtained showed that after deposition the organic characteristics of these sediments were altered according to their environment. Thus, compared to river-transported fine particulate organic matter (FPOM), samples from the lake bottom sediments showed increases in carbon and nitrogen concentrations, and decreases in 6'3C values due to the low isotopic composition of the particulate organic carbon in the lakes. Samples from areas covered by grasses had lower nitrogen and carbon relative to FPOM. The isotopic composition was changed by organic matter produced by the grasses, becoming less negative in 6'3C in the downriver direction. In the vegetation-free samples, collected over areas that had been recently drained, the isotopic composition did not change in relation to FPOM, but a decrease in carbon and nitrogen was observed.
Differentiating glacio‐eustacy and tectonics; a case study involving dinoflagellate cysts from the Eocene–Oligocene transition of the Pindos Foreland Basin (NW Greece)

In an attempt to discriminate between tectonically induced sea‐level changes and glacio‐eustacy, the Ekklissia and Arakthos sections (Epirus, NW Greece) are examined, applying (dinocyst) palynology, sedimentology and magnetostratigraphy. The sections, located in the Pindos Foreland Basin, both comprise the transition from pelagic limestones to hemipelagic silty clays and turbidite sandstones, reflecting the onset of flysch sedimentation as a result of the Pindos thrust activity. Despite an overall tectonic overprint, relative changes of sea level can be reconstructed, using (i) continental/marine palynomorph ratios, (ii) relative abundance of inshore and offshore dinoflagellate cysts, and (iii) taxa indicative of relatively cold and warm sea‐surface temperature, that can be calibrated against the Global Polarity Time Scale (GPTS). Increased fluxes of marginal marine and continental palynomorphs coincide with colder periods on a ‘third‐order’ scale, which thus appear to be related to glacio‐eustatic trends in sea‐level. The larger scale is attributed to the increasing effect of tectonics and acts on a ‘second‐order scale’.
Gly56 in the synthetic site of isoleucyl‐tRNA synthetase confers specificity and maintains communication with the editing site

Isoleucyl‐tRNA synthetase (IleRS) links isoleucine to cognate tRNA via the Ile‐AMP intermediate. Non‐cognate valine is often mistakenly recognized as the IleRS substrate; therefore, to maintain the accuracy of translation, IleRS hydrolyzes Val‐AMP within the synthetic site (pre‐transfer editing). As this activity is not efficient enough, Val‐tRNAIle is formed and hydrolyzed in the distant post‐transfer editing site. A strictly conserved synthetic site residue Gly56 was previously shown to safeguard Ile‐to‐Val discrimination during aminoacyl (aa)‐AMP formation. Here, we show that the Gly56Ala variant lost its specificity in pre‐transfer editing, confirming that this residue ensures the selectivity of all synthetic site reactions. Moreover, we found that the Gly56Ala mutation affects IleRS interaction with aa‐tRNA likely by disturbing tRNA‐dependent communication between the two active sites.