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We report the results of a comparative analysis focusing on grain size, mineralogical composition and spectral reflectance values (400-2500 nm) of cryoconite samples collected from Jakobshavn Isbræ, West Greenland, and Canada Glacier, McMurdo Dry Valleys, Antarctica. The samples from the Greenland site were composed of small particles clumped into larger rounded agglomerates, while those from the site in Antarctica contained fragments of different sizes and shapes. Mineralogical analysis indicates that the samples from Jakobshavn Isbræ contained a higher percentage of quartz and albite, whereas those from Canada Glacier contained a higher percentage of amphibole, augite and biotite. Spectral measurements confirmed the primary role of organic material in reducing the reflectance over the measured spectrum. The reflectance of the samples from the Antarctic site remained low after the removal of organic matter because of the higher concentration of minerals with low reflectance. The reflectance of dried cryoconite samples in the visible region was relatively low (e.g. between ∼0.1 and ∼0.4) favouring increased absorbed solar radiation. Despite high reflectance values in the shortwave infrared region, the effect of the presence of cryoconite is negligible at infrared wavelengths where ice reflectance is low.
The CuInSe2 and CuSbSe2 ternary compounds and alloys of the (CuSbSe2)1-x·(CuInSe2)x system with the mole fraction of CuInSe2 (x) equal to 0.05, 0.15, 0.25, 0.375, 0.50, 0.625, 0.75, 0.85, and 0.95 were prepared and the phase relations in this system were investigated by X-ray powder diffraction, optical microscopy, and scanning electron microscopy. It was shown that the alloys of the CuSbSe2-CuInSe2 system are biphasic at room temperature in the whole range of compositions, and the limits of solubility for CuSbSe2 in CuInSe2 and for CuInSe2 in CuSbSe2 do not exceed 0.001 mole fraction.
To provide a richer understanding of food access and purchasing practices among US urban food desert residents and their association with diet and BMI.
Data on food purchasing practices, dietary intake, height and weight from the primary food shopper in randomly selected households (n 1372) were collected. Audits of all neighbourhood food stores (n 24) and the most-frequented stores outside the neighbourhood (n 16) were conducted. Aspects of food access and purchasing practices and relationships among them were examined and tests of their associations with dietary quality and BMI were conducted.
Two low-income, predominantly African-American neighbourhoods with limited access to healthy food in Pittsburgh, PA, USA.
Household food shoppers.
Only one neighbourhood outlet sold fresh produce; nearly all respondents did major food shopping outside the neighbourhood. Although the nearest full-service supermarket was an average of 2·6 km from their home, respondents shopped an average of 6·0 km from home. The average trip was by car, took approximately 2 h for the round trip, and occurred two to four times per month. Respondents spent approximately $US 37 per person per week on food. Those who made longer trips had access to cars, shopped less often and spent less money per person. Those who travelled further when they shopped had higher BMI, but most residents already shopped where healthy foods were available, and physical distance from full-service supermarkets was unrelated to weight or dietary quality.
Improved access to healthy foods is the target of current policies meant to improve health. However, distance to the closest supermarket might not be as important as previously thought, and thus policy and interventions that focus merely on improving access may not be effective.
Local structural and metabolic as well as inter-regional connectivity abnormalities have been implicated in the neuropathology of major depressive disorder (MDD). How local tissue properties affect intrinsic functional connectivity is, however, unclear. Using a cross-sectional, multi-modal imaging approach, we investigated the relationship between local cortical tissue abnormalities and intrinsic resting-state functional connectivity (RSFC) in MDD.
A total of 20 MDD in-patients and 20 healthy controls underwent magnetic resonance imaging at 3 T for structural and functional imaging. Whole-brain cortical thickness was calculated and compared between groups. Regions with reduced cortical thickness defined seeds for subsequent whole-brain RSFC analyses. Contributions of structural tissue abnormalities on inter-regional RSFC were explicitly investigated.
Lower cortical thickness was observed in MDD in the right dorsomedial prefrontal cortex (PFC), superior temporal gyrus/temporal pole, middle-posterior cingulate cortex, and dorsolateral PFC. No differences in local fractional amplitude of low-frequency fluctuations were observed. Lower thickness in patients' dorsomedial PFC further directly and selectively affected its RSFC with the precuneus, which was unaffected by symptom severity. No effects of cortical thickness in other regions showing abnormal thickness were observed to influence functional connectivity.
Abnormal cortical thickness in the dorsomedial PFC in MDD patients was observed to selectively and directly affect its intrinsic connectivity with the precuneus in MDD patients independent of depression severity, thereby marking a potential vulnerability for maladaptive mood regulation. Future studies should include an unmedicated sample and replicate findings using independent component analysis to test for morphometric effects on network integrity.
Studies including patients with depression in the course of bipolar disorder I or II indicate lithium's effectiveness in the treatment and prevention of bipolar depression. A handful of studies have focused on the use of antidepressants as maintenance treatment for bipolar patients. Long-standing concerns that antidepressant treatment of bipolar depression may induce a switch to mania, an onset of rapid cycling, or treatment resistance. This chapter lists out various antidepressants that include quetiapine, lamotrigine, olanzapine/fluoxetine, aripiprazole, ziprasidone, risperidone, carbamazepine and valproate. The other treatments for bipolar depression include electroconvulsive therapy, deep brain stimulation and transcranial magnetic stimulation. As a secondary strategy, based on existing data, it seems reasonable to use antidepressants in combination with a mood stabilizer, with attention paid to possible emergence of manic/hypomanic symptoms. Despite widespread usage, the efficacy of lamotrigine for either acute or maintenance treatment of bipolar depression remains in question.
The first magneto—transport data taken on thin pseudomorphic FeSi films with the CsCl structure are presented. FeSi appears to be a Kondo system with a Kondo temperature of TK ∼ 15 K. On air-exposed films which have not been protected by a Si-cap an ultrathin magnetic oxide is formed leading to large anomalies in the Hall effect and the magnetoresistance as the film thickness approaches 20 Å.
In order to better understand the mechanics of metallization structures having very fine features, we performed in-situ, temperature-dependent X-ray strain measurements on Al-Cu films patterned into gratings with linewidths of 0.2-0.8μm, with and without a dielectric covering In comparison with earlier work on coarser structures, we find larger strains and less hysteresis, indicating an increased yield stress. The stress in unpassivated lines is almost independent of the linewidth. The slope of the stress/temperature curves for passivated lines increases with decreasing linewidth, so that the compressive stress at 500°C reaches 900MPa for the narrowest lines. The tensile stress at RT is smaller for the narrower lines, suggesting that these lines may not stress-void as much as wider ones. The significance of these results for stress voiding and electromigration will be discussed.
CuxGaySe2 MOCVD and PVD grown films were structurally and optically characterized by Raman, Micro-Raman and photoluminescence spectroscopy. Defect related photoluminescence excitation with wavelengths varying across the material band gap reveals: a) in Cu-rich CuGaSe2 films, three band edge splitting due to the spin-orbit interaction and the crystal field, and donor-acceptor pair recombination between a shallow donor and two different acceptor levels, and b) in Ga-rich CuGaSe2 films, donor-acceptor pair transitions between quasi-continua of donor and acceptor levels related to potential fluctuations. Raman spectra of CuxGaySe2films, excited by laser light near and below the material band gap, show intense modes at 197cm-1, 187cm-1, and 277cm-1, which can be used as indicators of crystallinity and Ga-content of the films. Polarization- and angular- dependent micro-Raman spectra of MOCVD CuGaSe2 indicate that CuxSey-crystallites, dispersed on the surface of Cu-rich films, are grown oriented with their c-axis perpendicular to the film surface.
The Sunrise balloon-borne solar observatory consists of a 1m aperture Gregory telescope, a UV filter imager, an imaging vector polarimeter, an image stabilization system and further infrastructure. The first science flight of Sunrise yielded high-quality data that reveal the structure, dynamics and evolution of solar convection, oscillations and magnetic fields at a resolution of around 100 km in the quiet Sun. Here we describe very briefly the mission and the first results obtained from the Sunrise data, which include a number of discoveries.
Our objective was to determine whether the addition of a broad-scope nurse practitioner (NP) would improve emergency department (ED) wait times, ED lengths of stay (LOS) and left-without-treatment (LWOT) rates. We hypothesized that the addition of a broad-scope NP during weekday ED shifts would result in shorter patient wait times, reduced LOS and fewer patients leaving the ED without treatment.
This prospective observational study was conducted in a busy urban free-standing community ED. Intervention shifts, with NP coverage, were compared with control shifts (similar shifts with emergency physicians [EPs] working independently). Primary outcomes included patient wait times, ED LOS and LWOT rates. Patient demographics, triage category, the provider seen, the time to provider and ED LOS were captured using an electronic database.
The addition of an NP was associated with a 12% increase in patient volume per shift and a 7-minute reduction in mean wait times for low-acuity patients. However, overall patient wait times and ED LOS did not differ between intervention and control shifts. During intervention shifts, EPs saw a smaller proportion of low-acuity patients and there was a trend toward a lower proportion of LWOT patients (11.9% v. 13.7%, p = 0.10).
Adding a broad-scope NP to the ED staff may lower the proportion of patients who leave without treatment, reduce the proportion of low-acuity patients seen by EPs and expedite throughput for a subgroup of less urgent patients. However, it did not reduce overall wait times or ED LOS in this setting.
The precise control of organic thin film processing by
organic vapor phase deposition (OVPD®) is presented and
analyzed on device level. OVPD® offers accurate and individual control of
deposition layer properties like mixing of several materials (co-deposition)
and the control of various morphologies by a wide process parameter space
given by, e.g. substrate temperature, deposition rate and pressure. The
benefit of precise co-deposition is demonstrated by an OLED with a sensitive
twofold-doped emissive layer and revealed a doping level of 0.26% for the
red dopant with a std. dev. of 0.38%. The effect of the various
morphologies is investigated by optimizing the efficiency of molecular
organic solar cells consisting of copper phthalocyanine (CuPc) and C60.
With defined process parameters efficiencies of up to 3.0% were
Our objective was to compare the emergency care provided by a nurse practitioner (NP) with that provided by emergency physicians (EPs), to identify emergency department (ED) patients appropriate for autonomous NP practice and to acquire data to facilitate the development of the clinical scope of practice recommendations for ED practice for NPs.
Using a comprehensive 3-part process, we selected and hired the best NP from 12 applicants. The NP was oriented to the operations of our free-standing community ED and incorporated in the care team, working in real time with EP preceptors during a 6-month, prospective clinical assessment comparing NP care with EP care. ED preceptors reviewed every case in real time with the NP and completed an explicit evaluation form to determine whether NP assessment, investigation, treatment and disposition were “all equivalent to emergency physician care” (AEEPC) or whether they differed. The proportion of AEEPC interactions was determined for 23 patient presentation categories. Our a priori assumption was that a patient presentation category might be suitable for autonomous NP practice if 50% of NP encounters in that category were rated as AEEPC. Descriptive data were presented for patient case mix, teaching domains and time criteria.
Eighty-three NP shifts and 711 patient encounters were evaluated by 21 EP preceptors. The NP saw a median of 8 patients per shift. In 43% of encounters, NP care was AEEPC. Highest AEEPC rates were found in the patient follow-up categories general follow-up (55.4%), diagnostic imaging (91.7%) and microbiology laboratory results (87.6%). NP scores over 50% were also seen for lacerations (63.6%) and isolated sore throats (53%). With teaching, NP performance improved over time.
With the exception of follow up–related complaints, simple lacerations and isolated sore throats, NP care differed substantially from EP care. Although NPs with extensive emergency experience and training might ultimately be able to function as autonomous ED care providers, Canadian EDs currently developing job descriptions for emergency NPs should focus on a model of collaborative practice with EPs.