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We present a novel ultrastable superconducting radio-frequency (RF) ion trap realized as a combination of an RF cavity and a linear Paul trap. Its RF quadrupole mode at 34.52 MHz reaches a quality factor of Q ≈ 2.3 × 105 at a temperature of 4.1 K and is used to radially confine ions in an ultralow-noise pseudopotential. This concept is expected to strongly suppress motional heating rates and related frequency shifts that limit the ultimate accuracy achieved in advanced ion traps for frequency metrology. Running with its low-vibration cryogenic cooling system, electron-beam ion trap, and deceleration beamline supplying highly charged ions (HCIs), the superconducting trap offers ideal conditions for optical frequency metrology with ionic species. We report its proof-of-principle operation as a quadrupole-mass filter with HCIs and trapping of Doppler-cooled 9Be+ Coulomb crystals. [ABSTRACT FROM AUTHOR]

The elemental composition of soil plays an essential role in crop nutrition, but losses from croplands can negatively impact soil fertility and water quality. We compared the impact of strip tillage (ST) and conventional tillage (CT) on element concentrations and loads in surface runoff and subsurface flow from plots under rotational cotton (Gossypium hirsutum L.) and peanut (Arachis hypogaea L.) production with winter cover cropping. Total element concentrations (calcium [Ca], iron [Fe], potassium [K], magnesium [Mg], manganese [Mn], sodium [Na], phosphorus [P], sulfur [S], silicon [Si], and zinc [Zn]) in surface runoff and subsurface flow samples were measured using Inductively Coupled Plasma with Optical Emission Spectroscopy (ICP-OES). Element loads were estimated by multiplying the element concentrations by the surface runoff and drainage volumes. Significantly greater (p = 0.05) surface runoff loads for all elements (with the exception of K and Zn) were observed from the CT compared with the ST treatment plots only in 2006, likely due to the combined effects of hydrology and the timing of gypsum amendments that year. Surface runoff was the primary hydrologic pathway for Fe, K, Mn, P, Si, and Zn loss while subsurface flow was the primary hydrologic pathway for Ca, Mg, and S loss with both tillage treatments. Lower concentrations of Ca, Mg, Na, and S in the subsurface flow with ST compared to CT suggest that this tillage practice, in conjunction with the proper timing of fertilizer and soil amendment applications (e.g., poultry litter and gypsum) can be an effective method for reducing element losses from croplands. This finding highlights the importance of conservation practices in sustaining healthy cropland soils while reducing element losses and associated environmental impacts. [ABSTRACT FROM AUTHOR]

The development of a nursing workforce that reflects the racial, ethnic, and cultural diversity of the nation's population continues to be a major challenge. Many minority disadvantaged nursing students face special challenges when successfully navigating their way and transitioning into the nursing curriculum. They need developmental or remedial courses (math, reading, and writing) and they face communication barriers and financial difficulties. The purpose of this pilot study was to identify the learning needs of minority nursing students and to implement a retention program to help them succeed. To determine the relationship between enrichment hours and course performances, an analysis of variance (ANOVA) was conducted using SPSS. While students who passed their courses had greater mean hours of enrichment than students who did not pass, the differences were not statistically significant. Students who graduated spent more hours in enrichment than students who did not graduate. Graduating students spent an average of 113 hours in enrichment during their program compared to students who did not graduate, and who spent an average of only 50 hours in enrichment. This difference was statistically significant [F = 44.50; df 1.98; p < .001]. [ABSTRACT FROM AUTHOR]

Examines the educational, employment and community adjustment outcomes of 106 graduates of a special school for youth with severe physical disabilities. Determining how well the educational system is meeting the needs of these students; Need to cultivate personal and family networks; Vocational rehabilitation agencies; Access to transportation; Method; Results; More.

Dissolved organic matter (DOM) represents an essential component of the carbon cycle and controls biogeochemical and ecological processes in aquatic systems. The composition and reactivity of DOM are determined by the spatial distribution of its sources and its residence time in a watershed. While the effects of agricultural land cover on DOM quality have been reported across spatial and temporal scales, the influence of riparian land cover on stream DOM composition has received little attention. Furthermore, the combined effects of riparian land cover and streamflow rates on DOM composition require investigation. To this end, a multi-year (2016-2018) DOM characterization study was conducted using bi-weekly water samples collected from seven sub-watersheds nested within the Little River Experimental Watershed (LREW) near Tifton, Georgia, USA. DOM optical properties were determined to assess compositional variations using UV-Vis and excitation-emission matrix (EEM) fluorescence spectroscopy coupled with parallel factor (PARAFAC) analysis. PARAFAC analysis indicated that DOM in the LREW was dominated by three humic-like fluorescing components of terrestrial, microbial, and anthropogenic origin and a protein-like component. DOM composition was influenced by riparian land cover and hydrology, and shifted towards recently produced, low molecular weight DOM with low aromaticity as the percentage of agricultural land within riparian wetlands increased. During periods of high discharge and high baseflow, the DOM pool was dominated by recalcitrant and terrestrial-derived material but shifted towards protein-like and microbial-derived with increasing cropland in the riparian area. The results of this two-year study indicate that the replacement of forested riparian buffers with agricultural land can result in altered DOM composition which may affect carbon cycling and downstream water quality in agricultural watersheds., Competing Interests: Declaration of competing interest The authors declare no competing financial interests., (Published by Elsevier B.V.)

Porous titanium cylinders were produced with a constant amount of temporary space holder (70 vol.%). Different interstitial contents were achieved by varying the starting powders (HDH vs. gas atomized) and manufacturing method (cold compaction without organic binders vs. warm compaction of MIM feedstocks). Interstitial contents (O, C, and N) as a function of manufacturing were measured by chemical analysis. Samples contained 0.34-0.58 wt.% oxygen, which was found to have the greatest effect on mechanical properties. Quasi-static mechanical tests under compression at low strain rate were used for reference and to define parameters for cyclic compression tests. Not unexpectedly, increased oxygen content increased the yield strength of the porous titanium. Cyclic compression fatigue tests were conducted using sinusoidal loading in a servo-hydraulic testing machine. Increased oxygen content was concomitant with embrittlement of the titanium matrix, resulting in significant reduction of compression cycles before failure. For samples with 0.34 wt.% oxygen, R, σ(min) and σ(max) were varied systematically to estimate the fatigue limit (~4 million cycles). Microstructural changes induced by cyclic loading were then characterized by optical microscopy, SEM and EBSD., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Several methods are used to generate a limit of detection for organic pollutants measured by gas chromatography-mass spectroscopy (GC-MS); all have theoretical and practical drawbacks. The current project investigated two common existing methods (statistical and empirical) for applicability to chromatographic properties from real samples, comparing these with a new proposed method using procedural blanks to estimate a minimum detectable peak area. Weaknesses of all three methods are discussed. The proposed method was superior to other examined methods in that it provided analyte-specific limits of detection linked to the recovery of mass-labeled internal standards for every analyte within every sample. Other identified quality assurance benefits included the following: enhanced protection against false positives; providing a sensitivity performance metric across batch, analyst, and instrument; enabling chemists with discretionary decisions specific to every analyte regarding detectability and interferences; and some strengths of both statistical and empirical techniques without major drawbacks of either. In marine sediment samples, the proposed method of calculating the limit of detection increased reporting of trace level (low- to subppb) GC-MS data for polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), organochlorine pesticides (OCPs), and polycyclic aromatic hydrocarbons (PAHs) by up to 400% compared with the statistical method.

The Pupil Evaluation Inventory was developed to assess peer ratings of the behavior of male and female children in grades one through nine. Three homogeneous and stable factors emerged from a factor analyss: Aggression, Withdrawal and Likeability. High interrater agreement between male and female raters, stability of factorial structure, high internal consistency, and moderate concurrent validity were found across sex and grade levels. Test-retest reliability was high for a separate sample of third and sixth graders. There was a tendency for higher internal consistency and teacher-peer correlations for the Aggression factor.

Tension reduction has often been implicated as a central cause of excessive alcohol consumption among alcoholics, based on the premise that drinking reduces tension and reinforces subsequent overconsumption. Also, cognitive and personality variables clearly mediate the effects of alcohol. Drinking may be a means of increasing the degree of control experienced over internal and external sources of tension. Integrated frontalis EMG levels for a group of 74 alcoholic patients were significantly greater than for 74 non-alcoholics. During a period of alcohol consumption, significant change scores were found between alcoholic (N = 18) and non-alcoholic (N = 18) groups for both EMG and experienced control (EC). Significant changes were found within both groups on EMG but only for the alcoholic group on EC. During a biofeedback period, there were significant differences between alcoholic (N = 12) and non-alcoholic (N = 12) groups on both baseline measures, EMG and EC. Increases in EC were significantly related to decreases in EMG in both groups.

The Adjustment Scales for Sociometric Evaluation of Secondary-School Students (ASSESS) was designed to assess peer ratings of the behavior of male and female adolescents. Five scales were developed and cross-validated: Aggression-Disruptiveness, Withdrawal, Anxiety, Social Competence, and Academic Difficulty. Evidence of adequate internal consistency and test-retest reliability was presented. Evaluations by male and female classmates were highly correlated. Sex and age differences accounted for only a small proportion of the total variance.