Preliminary Investigation of the Ground-Water Resources of Baxter, Fulton, Izard and Sharp Counties, Arkansas

One hundred and seventy-seven drillers\u27 well reports were used to investigate the groundwater resources of Baxter, Fulton, Izard, and Sharp counties. The most widely utilized aquifer zone is composed of the Cotter and Jefferson City dolomites. The well depths range from 30 to 740 ft. with a mean and median of 264 and 225 ft., respectively. The drillers\u27 yield estimates range from 1 to 50 gpm with a mean of 12.0 gpm and a median of 10 gpm. The piezometric surface has an average hydraulic gradient of 9 ft./mile with groundwater discharge occurring along the Spring and White Rivers. Overlying the Cotter-Jefferson City aquifer is the Powell Dolomite aquifer. Well depths range from 43 to 275 ft. with a mean and median of 137 and 114 ft., respectively. Driller estimated yields range from 7 to 40 gpm with a mean and median of 18 and 15 gpm, respectively. The Everton Aquifer is composed of a complex series of interfingering sandstones and carbonate layers that may act collectively or Individually as aquifers. Well depths in this aquifer range from 8 to 812 ft. with a mean of 338 ft. and a median of 500 ft. Yields range from 1 to 40 gpm with a mean and median of 11 and 7 gpm, respectively. The least productive and least utilized, but shallowest aquifer is the St. Peter Sandstone aquifer which has a depth range of 55 to 113 ft. with a mean and median of 80 and 85 ft., respectively. The yield ranges from 1 to 20 gpm with a mean and median of 9 and 5 gpm, respectively. The Spearman Rank Correlation procedure was used to compare well yields (gpm), well depth, regolith thickness, depth to water, and piezometric surface elevation of the Cotter-Jefferson City aquifer. At ∝ = 0.1, the following relationships were established: 1) greater yield at shallow well depths, 2) greater yield where the water table is closer to the surface, 3) thicker regolith in deeper wells, and thicker regolith with increased depth to water. These correlations indicate the strong control on water movement by fractures in the aquifer, and closing off of fractures at depth, and the control of regolith thickness by depth to water rather than fracture proximity

Commentary: From 'sense of number' to 'sense of magnitude' - The role of continuous magnitudes in numerical cognition

Unlike abstract ones in mathematics, concrete sets of elements in the real world have continuous physical properties, such as overall area and density. The dominant view has it that humans can estimate the discrete numerosities of such sets independently of the co-varying continuous magnitudes; i.e., that humans have a “sense of number”. It has indeed been claimed that various animals, ranging from monkeys to tiny fish, have this sense too. A recent paper by Leibovich et al. (2016) questions all of this (see also Gebuis et al., 2016; Morgan et al., 2014) and argues convincingly that numerosity estimation is not independent from continuous magnitudes but relies on them; that we have not a “sense of number” but a “sense of magnitude”. Yet the authors fail to cite a classic article that made the very same argument 25 years ago, and—unlike Leibovich et al.—supported it with a quantitative model (Allik and Tuulmets, 1991). Although neither density, nor overall area, nor any other single continuous magnitude can provide reliable information about numerosity, Leibovich et al. imply that all of them together can; they suggest that “statistical learning” will take care of extracting this information and turn numerosity estimates out of it. How statistical learning achieves this feat and whether the resulting numerosity estimates will fit observed ones remains, unfortunately, unclear. Allik and Tuulmets’s alternative “occupancy” model has its limits (e.g., Bertamini et al., 2016; Kramer et al., 2011) but it is specific, it is quantitative, and it predicts observed numerosity estimation surprisingly well with just a single free parameter

Miscellanea. Folyóirat-referátumok.

Folyóirat-referátumok. A jövő medicinája Virtuális realitás az emberi anatómia tanulmányozására. (Virtual reality educational tool for human anatomy.) Izard SG, Méndez JA, Palomera PR (levelező szerző: Pablo Ruisoto Palomera, European University of Madrid, Madrid, Spanyolország; e-mail: [email protected]): J Med Syst. 2017; 41: 76. | Kardiológia A génvizsgálat mutathatja a szubklinikus coronariabetegség gyanúját és a statin védőhatását. (Gene test could predict subclinical CHD risk, statin benefit.) Busko M.: Medscape, November 3, 2017