Evidence of Energy Exchanges Accompanying Scattering of Atoms by Crystals

The distribution of mercury atoms scattered from NaCl KCl, KBr KI has been studied by means of an ionization gauge as a function of angle of incidence and temperatures of scatterer and incident beam. The direction of maximum intensify makes an angle with the crystal normal not equal to the angle of incidence but always slightly less

Student perspectives on using Google Glass recordings to assess their communicative and clinical skills with standardized patients

Introduction This exploratory study evaluated student perceptions of their ability to self- and peer assess (i) interpersonal communication skills and (ii) clinical procedures (a head and neck examination) during standardised patient (SP) interactions recorded by Google Glass compared to a static camera. Methods Students compared the Google Glass and static camera recordings using an instrument consisting of 20 Likert-type items and four open- and closed-text items. The Likert-type items asked students to rate how effectively they could assess specific aspects of interpersonal communication and a head and neck examination in these two different types of recordings. The interpersonal communication items included verbal, paraverbal and non-verbal subscales. The open- and closed-text items asked students to report on more globally the differences between the two types of recordings. Descriptive and inferential statistical analyses were conducted for all survey items. An inductive thematic analysis was conducted to determine qualitative emergent themes from the open-text questions. Results Students found the Glass videos more effective for assessing verbal (t22 = 2.091, P = 0.048) and paraverbal communication skills (t22 = 3.304, P = 0.003), whilst they reported that the static camera video was more effective for assessing non-verbal communication skills (t22 = −2.132, P = 0.044). Four principle themes emerged from the students' open-text responses comparing Glass to static camera recordings for self- and peer assessment: (1) first-person perspective, (2) assessment of non-verbal communication, (3) audiovisual experience and (4) student operation of Glass. Discussion and conclusion Our findings suggest that students perceive that Google Glass is a valuable tool for facilitating self- and peer assessment of SP examinations because of students’ perceived ability to emphasise and illustrate communicative and clinical activities from a first-person perspective

Changes in mental health services and suicide mortality in Norway: an ecological study

<p>Abstract</p> <p>Background</p> <p>Mental disorders are strongly associated with excess suicide risk, and successful treatment might prevent suicide. Since 1990, and particularly after 1998, there has been a substantial increase in mental health service resources in Norway. This study aimed to investigate whether these changes have had an impact on suicide mortality.</p> <p>Methods</p> <p>We used Poisson regression analyses to assess the effect of changes in five mental health services variables on suicide mortality in five Norwegian health regions during the period 1990-2006. These variables included: number of man-labour years by all personnel, number of discharges, number of outpatient consultations, number of inpatient days, and number of hospital beds. Adjustments were made for sales of alcohol, sales of antidepressants, education, and unemployment.</p> <p>Results</p> <p>In the period 1990-2006, we observed a total of 9480 suicides and the total suicide rate declined by 26%. None of the mental health services variables were significantly associated with female or male suicide mortality in the adjusted analyses (p > 0.05). Sales of antidepressants (adjusted Incidence Rate Ratio = 0.98; 95% CI = 0.97-1.00) and sales of alcohol (adjusted IRR = 1.41; 95% CI = 1.18-1.72) were significantly associated with female suicide mortality; education (adjusted IRR = 0.86; 95% CI = 0.79-0.94) and unemployment (adjusted IRR = 0.91; 95% CI = 0.85-0.97) were significantly associated with male suicide mortality.</p> <p>Conclusions</p> <p>The adjusted analyses in the present study indicate that increased resources in Norwegian mental health services in the period 1990-2006 were statistically unrelated to suicide mortality.</p

Frontier Orbital Degeneracy: A new Concept for Tailoring the Magnetic State in Organic Semiconductor Adsorbates

Kondo resonances in molecular adsorbates are an important building block for applications in the field of molecular spintronics. Here, we introduce the novel concept of using frontier orbital degeneracy for tailoring the magnetic state, which is demonstrated for the case of the organic semiconductor 1,4,5,8,9,11-Hexaazatriphenylenehexacarbonitrile (HATCN, C18N12) on Ag(111). Low-temperature scanning tunneling microscopy/spectroscopy (LT-STM/STS) measurements reveal the existence of two types of adsorbed HATCN molecules with distinctly different appearances and magnetic states, as evident from the presence or absence of an Abrikosov-Suhl-Kondo resonance. Our DFT results show that HATCN on Ag(111) supports two almost isoenergetic states, both with one excess electron transferred from the Ag surface, but with magnetic moments of either 0 or 0.65 uB. Therefore, even though all molecules undergo charge transfer of one electron from the Ag substrate, they exist in two different molecular magnetic states that resemble a free doublet or an entangled spin state. We explain how the origin of this behavior lies in the twofold degeneracy of the lowest unoccupied molecular orbitals of gas phase HATCN, lifted upon adsorption and charge-transfer from Ag(111). Our combined STM and DFT study introduces a new pathway to tailoring the magnetic state of molecular adsorbates on surfaces, with significant potential for spintronics and quantum information science

Solvent, salt and high pressure effects on the rate and equilibrium constants for the formation of tri-n-butylphosphoniumdithiocarboxylate

Solvent, salt and high pressure effects on the rate and equilibrium constants for the formation of tri-n-butylphosphoniumdithiocarboxylate at 298.2 K are reported. This equilibrium is shifted to the phosphobetaine in polar solvents, salt solutions and under high external pressure. The reaction volume changes dramatically on going from less polar diethyl ether (-69 cm3 mol-1) and tetrahydrofurane (THF) (-66 cm3 mol -1), to more polar acetonitrile (-39 cm3 mol-1) and acetone (-38 cm3 mol-1). Copyright © 2010 John Wiley & Sons, Ltd

Precision Dual-Aquifer Dewatering at a Low Level Radiological Cleanup in New Jersey

Cleanup of low-level radioactive wastes at the Wayne Interim Storage Site (WISS), Wayne, New Jersey during the period October, 2000 through November, 2001 required the design, installation and operation of a dual-aquifer dewatering system to support excavation of contaminated soils. Waste disposal pits from a former rare-earth processing facility at the WISS had been in contact with the water table aquifer, resulting in moderate levels of radionuclides being present in the upper aquifer groundwater. An uncontaminated artesian aquifer underlies the water table aquifer, and is a localized drinking water supply source. The lower aquifer, confined by a silty clay unit, is flowing artesian and exhibits potentiometric heads of up to 4.5 meters above grade. This high potentiometric head presented a strong possibility that unloading due to excavation would result in a ''blowout'', particularly in areas where the confining unit was &lt; 1 meter thick. Excavation of contaminated materials w as required down to the surface of the confining unit, potentially resulting in an artesian aquifer head of greater than 8 meters above the excavation surface. Consequently, it was determined that a dual-aquifer dewatering system would be required to permit excavation of contaminated material, with the water table aquifer dewatered to facilitate excavation, and the deep aquifer depressurized to prevent a ''blowout''. An additional concern was the potential for vertical migration of contamination present in the water table aquifer that could result from a vertical gradient reversal caused by excessive pumping in the confined system. With these considerations in mind, a conceptual dewatering plan was developed with three major goals: (1) dewater the water table aquifer to control radionuclide migration and allow excavation to proceed; (2) depressurize the lower, artesian aquifer to reduce the potential for a ''blowout''; and (3) develop a precise dewatering level control mechanism to insure a vertical gradient reversal did not result in cross-contamination. The plan was executed through a hydrogeologic investigation culminating with the design and implementation of a complex, multi-phased dual-aquifer dewatering system equipped with a state of the art monitoring network