Discovery of the Cobalt Isotopes

Twenty-six cobalt isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.Comment: to be published in Atomic Data and Nuclear Data Table

State of the science on controversial topics: missing maxillary lateral incisors--a report of the Angle Society of Europe 2012 meeting.

BACKGROUND: The optimal long-term management of the congenitally missing maxillary lateral incisor continues to cause controversy within the specialty. The Angle Society of Europe meeting 2012 dedicated a day to address some of the current controversies relating to the management of these missing lateral incisors. FINDINGS: The format of the day consisted of morning presentations and afternoon breakout sessions to discuss a variety of questions related to the management of missing lateral incisors. CONCLUSIONS: The consensus viewpoint from this day was that the care of patients with congenitally missing lateral incisors is best achieved through a multi-disciplinary approach. The current evidence base is weak, and further well-designed, prospective trials are needed

In-Situ Nuclear Magnetic Resonance Investigation of Strain, Temperature, and Strain-Rate Variations of Deformation-Induced Vacancy Concentration in Aluminum

Critical strain to serrated flow in solid solution alloys exhibiting dynamic strain aging (DSA) or Portevin–LeChatelier effect is due to the strain-induced vacancy production. Nuclear magnetic resonance (NMR) techniques can be used to monitor in situ the dynamical behavior of point and line defects in materials during deformation, and these techniques are nondestructive and noninvasive. The new CUT-sequence pulse method allowed an accurate evaluation of the strain-enhanced vacancy diffusion and, thus, the excess vacancy concentration during deformation as a function of strain, strain rate, and temperature. Due to skin effect problems in metals at high frequencies, thin foils of Al were used and experimental results correlated with models based on vacancy production through mechanical work (vs thermal jogs), while in situ annealing of excess vacancies is noted at high temperatures. These correlations made it feasible to obtain explicit dependencies of the strain-induced vacancy concentration on test variables such as the strain, strain rate, and temperature. These studies clearly reveal the power and utility of these NMR techniques in the determination of deformation-induced vacancies in situ in a noninvasive fashion.

The Role of Implant Position on Longâ Term Success

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141259/1/cap0187.pd

An investigation into aripiprazole's partial D(2) agonist effects within the dorsolateral prefrontal cortex during working memory in healthy volunteers

Rationale: Working memory impairments in schizophrenia have been attributed to dysfunction of the dorsolateral prefrontal cortex (DLPFC) which in turn may be due to low DLPFC dopamine innervation. Conventional antipsychotic drugs block DLPFC D2 receptors, and this may lead to further dysfunction and working memory impairments. Aripiprazole is a D2 receptor partial agonist hypothesised to enhance PFC dopamine functioning, possibly improving working memory. Objectives: We probed the implications of the partial D2 receptor agonist actions of aripiprazole within the DLPFC during working memory. Investigations were carried out in healthy volunteers to eliminate confounds of illness or medication status. Aripiprazole’s prefrontal actions were compared with the D2/5-HT2A blocker risperidone to separate aripiprazole’s unique prefrontal D2 agonist actions from its serotinergic and striatal D2 actions that it shares with risperidone. Method: A double-blind, placebo-controlled, parallel design was implemented. Participants received a single dose of either 5 mg aripiprazole, 1 mg risperidone or placebo before performing the n-back task whilst undergoing fMRI scanning. Results: Compared with placebo, the aripiprazole group demonstrated enhanced DLPFC activation associated with a trend for improved discriminability (d’) and speeded reaction times. In contrast to aripiprazole’s neural effects, the risperidone group demonstrated a trend for reduced DLPFC recruitment. Unexpectedly, the risperidone group demonstrated similar effects to aripiprazole on d’ and additionally had reduced errors of commission compared with placebo. Conclusion: Aripiprazole has unique DLPFC actions attributed to its prefrontal D2 agonist action. Risperidone’s serotinergic action that results in prefrontal dopamine release may have protected against any impairing effects of its prefrontal D2 blockade

Bimodal volcanism of the High Lava Plains and Northwestern Basin and Range of Oregon: Distribution and tectonic implications of age-progressive rhyolites

Multiple episodes of Oligocene and younger silicic volcanism are represented in the high lava plateau of central and southeastern Oregon. From 12 Ma to Recent, volcanism is strongly bimodal with nearly equal volumes of basalt and rhyolite. It is characterized by moderate to high silica (SiO₂ > 72 wt. %) rhyolitic tuffs and domes that are younger to the west, and widespread, tholeiitic basalts that show no temporal pattern. We report 18 new ⁴⁰Ar/³⁹Ar incremental heating ages on rhyolites, and establish that the timing of the age-progressive rhyolites is decoupled from basaltic pulses. This work expands on that of previous workers by clearly linking the High Lava Plains (HLP) and northwestern-most Basin and Range (NWBR) rhyolite volcanism into a single age-progressive trend. The spatial-temporal relationship of the rhyolite outcrops and regional tectonics indicate that subsidence due to increasingly dense crust creates large, primarily sediment-filled basins within the more volcanically active HLP. The west-northwest age progression in rhyolitic volcanism is counter to the trend expected for a quasi-stationary mantle upwelling relative to North American plate motion. We attribute the rhyolitic age progression to mantle upwelling in response to slab rollback and steepening, and this is consistent with mantle anisotropy under the region and analog slab rollback models. This removes the necessity of deep mantle plume involvement. Laboratory experimental studies indicate that the geometry of the downgoing slab can focus upwelling or asthenospheric counterflow into a constricted band, resulting in greater volcanic volumes in the HLP as compared to the NWBR. Keywords: high lava plains; bimodal volcanism; intraplate volcanism; Ar-Ar geochronology; Oregon geology; slab rollback

Geochronology of age-progressive volcanism of the Oregon High Lava Plains : implications for the plume interpretation of Yellowstone

The High Lava Plains province (HLP) is a late Cenozoic bimodal volcanic field at the northern margin of the Basin and Range province in southeastern Oregon that hosts a westward younging trend of silicic volcanism that crudely mirrors northeastward migration of silicic volcanism along the Yellowstone–Snake River Plain (YSRP) trend. We present ⁴⁰Ar/³⁹Ar ages for 19 rhyolite domes, 5 rhyolite ash flow tuffs, and 34 basaltic lavas from the HLP. The previously identified trend of westward migration of HLP rhyolites is confirmed. The rate of propagation is ∼33 km/m.y. from 10 to 5 Ma, slowing to ∼13 km/m.y. after 5 Ma. The duration of silicic volcanism at any locus is ∼2 m.y. Three older HLP dacite domes yielded ages of ∼15.5 Ma. Basalts are not age progressive. We identify several episodes of increased basaltic activity at 7.5–7.8, 5.3–5.9, and 2–3 Ma, with the younger episode likely continuing into the Recent. The HLP and YSRP trends emerged from the axis of middle Miocene basaltic volcanism of the Columbia River and Steens basalts. We propose a model in which (1) Miocene flood basalts and widespread silicic rocks are the result of emplacement of a plume head near the craton margin, enhanced by flow up a topographic gradient along the base of the lithosphere at the craton margin; (2) the HLP trend is the result of westward flow originating at the craton margin; and (3) the YSRP trend is the trace of the motion of the North American plate over the tail of the plume

Prolonged history of silicic peralkaline volcanism in the eastern Pacific Ocean

Socorro Island, Mexico, is an alkaline and peralkaline volcanic island located in the eastern Pacific Ocean on a mid-ocean ridge spreading center that was abandoned at ∼3.5 Ma. Silicic peralkaline rocks comprise up to 80% of the surface of the island, rendering Socorro virtually unique in the Pacific Ocean. Precise, replicate 40Ar/39Ar ages of 21 peralkaline trachytes and rhyolites reveal a history of episodic volcanic activity from ∼540 to 370 ka that may have culminated with caldera formation; repose periods between these episodes may have had maximum duration of ∼30 kyr. After up to 200 kyr of quiescence, 40Ar/39Ar ages indicate that postcaldera silicic peralkaline activity commenced by 180 ka, forming the Cerro Evermann Formation. Postcaldera mafic alkaline lavas of the Lomas Coloradas Formation erupted dominantly between 70 and 150 ka based upon relative age relations. The dominant lithology of precaldera and syncaldera silicic peralkaline deposits on Socorro is nonfragmental and nonvesicular and lacks lithic fragments and fiamme; despite this, numerous lines of evidence including welding zonation, presence of a proximal ignimbrite or co-ignimbrite deposit, association with a caldera, and compositional heterogeneity within eruptive units suggest that they are dominantly ash flow tuffs. A change in eruptive style, from predominantly explosive to predominantly effusive, followed caldera formation and suggests that a change in the efficacy of magma degassing may be linked to caldera formation. On the basis of the presence of a caldera, the magma chamber associated with Socorro Island is shallow and probably resides within the upper oceanic crust or the edifice. This together with a prolonged history of silicic magmatism indicates that intrusion of mafic magma maintained thermal viability of the magmatic plumbing system. The minimum calculated growth rate for the entire volcanic edifice (7 × 10−4 km3/yr) exceeds those of nonhotspot off-axis volcanoes in the Pacific by almost an order of magnitude. Eruption rates for subaerial phases on Socorro may be several orders of magnitude smaller than this growth rate and are comparable to subaerial eruption rates of isolated ocean islands related to mantle plumes

Biochemical and developmental characterization of carbonic anhydrase II from chicken erythrocytes

<p>Abstract</p> <p>Background</p> <p>Carbonic anhydrase (CA) of the chicken has attracted attention for a long time because it has an important role in the eggshell formation. The developmental profile of CA-II isozyme levels in chicken erythrocytes has not been determined or reported. Furthermore, the relations with CA-II in erythrocyte and egg production are not discussed. In the present study, we isolated CA-II from erythrocytes of chickens and determined age-related changes of CA-II levels in erythrocytes.</p> <p>Methods</p> <p>Chicken CA-II was purified by a combination of column chromatography. The levels of CA-II in the hemolysate of the chicken were determined using the ELISA system in blood samples from 279 female chickens, ages 1 to 93 weeks, 69 male chickens, ages 3 to 59 weeks and 52 weeks female Araucana-chickens.</p> <p>Results</p> <p>The mean concentration of CA-II in hemolysate from 1-week-old female was 50.8 ± 11.9 mg/g of Hb. The mean levels of CA-II in 25-week-old (188.1 ± 82.6 mg/g of Hb), 31-week-old (193.6 ± 69.7 mg/g of Hb) and 49-week-old (203.8 ± 123.5 mg/g of Hb) female-chickens showed the highest level of CA-II. The levels of CA-II in female WL-chickens significantly decreased at 63 week (139.0 ± 19.3 mg/g of Hb). The levels of CA-II in female WL-chicken did not change from week 63 until week 93.The mean level of CA-II in hemolysate of 3-week-old male WL-chickens was 78.3 ± 20.7 mg/g of Hb. The levels of CA-II in male WL-chickens did not show changes in the week 3 to week 59 timeframe. The mean level of CA-II in 53-week-old female Araucana-chickens was 23.4 ± 1.78 mg/g of Hb. These levels of CA-II were about 11% of those of 49-week-old female WL-chickens. Simple linear regression analysis showed significant associations between the level of CA-II and egg laying rate from 16 week-old at 63 week-old WL-chicken (p < 0.01).</p> <p>Conclusions</p> <p>Developmental changes and sexual differences of CA-II concentration in WL-chicken erythrocytes were observed. The concentration of CA-II in the erythrocyte of WL-chicken was much higher than that in Araucana-chicken (p < 0.01).</p

Promoting More Physical Activity and Less Sedentary Behaviour During the COVID-19 Situation – SportStudisMoveYou (SSMY): A Randomized Controlled Trial

Objective: To determine the effect of an innovative, online-based intervention, addressing the possible decline of physical activity (PA) and increase of sedentary behavior (SB) during COVID-19 stay at home restrictions in Switzerland. Methods: This study investigated the effect of a two-week, social cognitive theory based, online-video moderate to vigorous (MV)PA or SB intervention on MVPA and SB behaviour and intention via a 3 group by 2 time point parallel randomized controlled trial during the COVID-19 pandemic. Adults (≥18 yo) were recruited over the internet between April 10th and April 19th 2020 (n = 129; 75.2% female; mean age = 29.0 [SD 11.8] years). Both intervention groups received five videos targeting either SB for the SB group or MVPA for the MVPA group and were compared to an attention control group (fruit and vegetable consumption). It was hypothesized that MVPA time and intention would increase for the MVPA group and the SB group would outperform control on SB behaviour and intention indicators. Results: No significant interactions were found for the MVPA group (n = 41) versus control (n = 40). Only one significant interaction was measured for the SB group (n = 48; intention of active breaks F = (2,114) = 5.84, p = 0.004, ηp2 = 0.09). Although mostly non-significant and small effects, the MVPA group showed results pointing in the hypothesized direction on all PA indicators and the SB on all SB indicators, respectively. Conclusion: Considering this study’s limitations (e.g. small intervention dose), video-based online PA and SB interventions seem promising and feasible. This approach is appropriate for COVID-19 and other stay at home situations