Silurian and Devonian Formations in Southeastern Indiana

Indiana Geological Survey Guidebook 1This conference was planned to provide an opportunity to observe and discuss outcrops of Silurian and Devonian rocks in southeastern Indiana. The broad aspects of the stratigraphy and fauna were emphasized since most persons attending were not familiar with these formations. It was hoped the discussions would help solve many problems concerning these rocks. Any assistance that can be provided in the subsurface identification and correlation of the counterparts of these formations in the surrounding basin areas will help make the conference a success. Campbell's (1942) recent reclassification of the Devonian will be especially interesting to those familiar with the older classification and terminology. The opportunity to become acquainted and discuss mutual problems was an important part of the program.Department of Geology, Indiana University; Indiana Division of Geology; Indiana Department of Conservatio

Substance use disorders in the farming population: Scoping review

Purpose The purpose of this scoping review is to summarize the current knowledge base in order to make recommendations for prevention and treatment of substance use disorders among the farming populations. Methods We conducted a scoping review of peer-reviewed articles published between January 1989 and September 2019. The search yielded 3,426 citations and the final review was conducted on 42 articles. The full review was conducted by 4 authors to extract information about the target population, data collection methods, and main results. Findings There were 21 articles on farmers and 21 articles on farmworkers. The majority of the articles were about alcohol. Overall, farmers had higher prevalence of risky alcohol consumption patterns than nonfarmers. The prevalence of risky alcohol consumption was also high among farmworkers compared to the general population. Risk factors for risky alcohol consumption included male gender, lower socioeconomic status, and psychological problems (eg, depression). Recommendations for prevention and intervention of alcohol disorders included policy development and implementation to curb alcohol access by taxation, screening of alcohol-related problems, and alternative means of recreation instead of alcohol consumption. Conclusions This review confirmed that alcohol-related problems are prevalent among farmers and farmworkers. More population-based research is called for to understand the additional risk factors of alcohol disorders and the prevalence of other substance-related disorders. Also, interventions should be tailored to the unique culture of farmers and farmworkers

Foraminifera from Mongolia

7 p. : ill., map ; 24 cm.Includes bibliographical references.pt. 1. Field relations / by L. Erskine Spock -- pt. 2. Descriptions of Foraminifera / by J.J. Galloway

Diversity of Free-Living Environmental Bacteria and Their Interactions With a Bactivorous Amoeba

A small subset of bacteria in soil interact directly with eukaryotes. Which ones do so can reveal what is important to a eukaryote and how eukaryote defenses might be breached. Soil amoebae are simple eukaryotic organisms and as such could be particularly good for understanding how eukaryote microbiomes originate and are maintained. One such amoeba, Dictyostelium discoideum, has both permanent and temporary associations with bacteria. Here we focus on culturable bacterial associates in order to interrogate their relationship with D. discoideum. To do this, we isolated over 250 D. discoideum fruiting body samples from soil and deer feces at Mountain Lake Biological Station. In one-third of the wild D. discoideum we tested, one to six bacterial species were found per fruiting body sorus (spore mass) for a total of 174 bacterial isolates. The remaining two-thirds of D. discoideum fruiting body samples did not contain culturable bacteria, as is thought to be the norm. A majority (71.4%) of the unique bacterial haplotypes are in Proteobacteria. The rest are in either Actinobacteria, Bacteriodetes, or Firmicutes. The highest bacterial diversity was found in D. discoideum fruiting bodies originating from deer feces (27 OTUs), greater than either of those originating in shallow (11 OTUs) or in deep soil (4 OTUs). Rarefaction curves and the Chao1 estimator for species richness indicated the diversity in any substrate was not fully sampled, but for soil it came close. A majority of the D. discoideum-associated bacteria were edible by D. discoideum and supported its growth (75.2% for feces and 81.8% for soil habitats). However, we found several bacteria genera were able to evade phagocytosis and persist in D. discoideum cells through one or more social cycles. This study focuses not on the entire D. discoideum microbiome, but on the culturable subset of bacteria that have important eukaryote interactions as prey, symbionts, or pathogens. These eukaryote and bacteria interactions may provide fertile ground for investigations of bacteria using amoebas to gain an initial foothold in eukaryotes and of the origins of symbiosis and simple microbiomes

Comparative metagenomic, phylogenetic and physiological analyses of soil microbial communities across nitrogen gradients

Terrestrial ecosystems are receiving elevated inputs of nitrogen (N) from anthropogenic sources and understanding how these increases in N availability affect soil microbial communities is critical for predicting the associated effects on belowground ecosystems. We used a suite of approaches to analyze the structure and functional characteristics of soil microbial communities from replicated plots in two long-term N fertilization experiments located in contrasting systems. Pyrosequencing-based analyses of 16S rRNA genes revealed no significant effects of N fertilization on bacterial diversity, but significant effects on community composition at both sites; copiotrophic taxa (including members of the Proteobacteria and Bacteroidetes phyla) typically increased in relative abundance in the high N plots, with oligotrophic taxa (mainly Acidobacteria) exhibiting the opposite pattern. Consistent with the phylogenetic shifts under N fertilization, shotgun metagenomic sequencing revealed increases in the relative abundances of genes associated with DNA/RNA replication, electron transport and protein metabolism, increases that could be resolved even with the shallow shotgun metagenomic sequencing conducted here (average of 75 000 reads per sample). We also observed shifts in the catabolic capabilities of the communities across the N gradients that were significantly correlated with the phylogenetic and metagenomic responses, indicating possible linkages between the structure and functioning of soil microbial communities. Overall, our results suggest that N fertilization may, directly or indirectly, induce a shift in the predominant microbial life-history strategies, favoring a more active, copiotrophic microbial community, a pattern that parallels the often observed replacement of K-selected with r-selected plant species with elevated N

A Multiproxy Database of Western North American Holocene Paleoclimate Records

Holocene climate reconstructions are useful for understanding the diverse features and spatial heterogeneity of past and future climate change. Here we present a database of western North American Holocene paleoclimate records. The database gathers paleoclimate time series from 184 terrestrial and marine sites, including 381 individual proxy records. The records span at least 4000 of the last 12 000 years (median duration of 10 725 years) and have been screened for resolution, chronologic control, and climate sensitivity. Records were included that reflect temperature, hydroclimate, or circulation features. The database is shared in the machine readable Linked Paleo Data (LiPD) format and includes geochronologic data for generating site-level time-uncertain ensembles. This publicly accessible and curated collection of proxy paleoclimate records will have wide research applications, including, for example, investigations of the primary features of ocean-atmospheric circulation along the eastern margin of the North Pacific and the latitudinal response of climate to orbital changes. The database is available for download at https://doi.org/10.6084/m9.figshare.12863843.v1 (Routson and McKay, 2020)

Heavy element production in a compact object merger observed by JWST

The mergers of binary compact objects such as neutron stars and black holes are of central interest to several areas of astrophysics, including as the progenitors of gamma-ray bursts (GRBs) 1, sources of high-frequency gravitational waves (GWs) 2 and likely production sites for heavy-element nucleosynthesis by means of rapid neutron capture (the r-process) 3. Here we present observations of the exceptionally bright GRB 230307A. We show that GRB 230307A belongs to the class of long-duration GRBs associated with compact object mergers 4–6 and contains a kilonova similar to AT2017gfo, associated with the GW merger GW170817 (refs. 7–12). We obtained James Webb Space Telescope (JWST) mid-infrared imaging and spectroscopy 29 and 61 days after the burst. The spectroscopy shows an emission line at 2.15 microns, which we interpret as tellurium (atomic mass A = 130) and a very red source, emitting most of its light in the mid-infrared owing to the production of lanthanides. These observations demonstrate that nucleosynthesis in GRBs can create r-process elements across a broad atomic mass range and play a central role in heavy-element nucleosynthesis across the Universe

Critical heat flux enhancement in the presence of stream-wise curvature

An experimental study was undertaken to evaluate a novel cooling concept designed to cool high power heat sources by forced convective boiling in the presence of stream-wise curvature. The critical heat flux, CHF, determines the maximum nucleate boiling heat transfer limit beyond which permanent damage to the heat source may result. Stream-wise flow curvature developed an artificial body force which propelled vapor away from the heater surface, thereby extending the nucleate boiling regime to higher heat fluxes. A parametric study was made to investigate the effects of surface curvature, heat length, system pressure, and flow velocity on CHF. Detailed flow visualization experiments conducted in linear and curved channel heaters improved the fundamental understanding of liquid-vapor exchange near the heater surface and helped to identify the trigger mechanism responsible for initiating CHF. Greater liquid contact was observed and higher CHF was measured for the curved heater surface compared to the linear heater surface at equal flow velocities. Flow visualization observations were used in conjunction with experimental measurements to develop a mechanistically based CHF model that explicitly accounted for the effects of a body force. The CHF model was based on geometrical arguments, a hydrodynamic two-phase flow model and an interfacial instability analysis. Experimental measurements taken in the linear and curved channel compared well with theoretical predictions. The primary contributions of this study are the development of a unique system designed to enhance CHF, the identification of hydrodynamic conditions necessary for triggering CHF and the verification of the stream-wise curvature enhancement effect on CHF