This study explores scholars' approaches to measure performance in nonprofit human service organizations. While acknowledging that each human service organization's unique mission makes it challenging to create a generalizable model across all nonprofit human service organizations, we propose three multidimensional frameworks for performance measurement derived from survey and qualitative data of organizations in this subsector. The frameworks will help researchers and practitioners rethink, adapt to, and reflect on the implications of their current methods of program performance measurement.
View Article and Find Full Text PDFBackground: The prognosis for patients with recurrent glioblastoma (GBM) is dismal, and the question of repeat surgery at time of recurrence is common. Re-operation in the management of these patients remains controversial, as there is no randomized evidence of benefit. An all-inclusive pragmatic care trial is needed to evaluate the role of repeat resection.
View Article and Find Full Text PDFEngineered nanomaterials (ENMs) have an enormous economic impact. In the surface coating industry, titanium dioxide (TiO2) and silicon dioxide (SiO2) nanoparticles are commonly incorporated into varnishes, paints, and finishing products. These ENMs are used for UV-active properties and self-cleaning activities, as well as for the durability and resistance they provide.
View Article and Find Full Text PDFQuestions still exist regarding which indicator better estimates worker's exposure to diesel particulate matter (DPM) and, especially for ultrafine particles (UFP), how exposure levels and the characteristics of the particles vary in workplaces with different exposure conditions. This study aimed to quantify and characterize DPM exposures in three workplaces with different exposure levels: an underground mine, a subway tunnel, and a truck repair workshop. The same sampling strategy was used and included measurements of the particle number concentration (PNC), mass concentration, size distribution, transmission electron microscopy (TEM), and the characterization of carbonaceous fractions.
View Article and Find Full Text PDFACS Appl Mater Interfaces
February 2019
Direct ink writing (DIW) combined with post-deposition thermal treatments is a safe, cheap, and accessible additive manufacturing (AM) method for the creation of metallic structures. Single-material DIW enables the creation of complex metallic 3D structures featuring overhangs, lengthy bridges, or enclosed hollows, but requires the printing supporting structures. However, the support printed from the same material becomes inseparable from the building structure after the thermal treatment.
View Article and Find Full Text PDFAnn Work Expo Health
March 2017
Objectives: This study was aimed at documenting and characterizing occupational exposure to single-walled carbon nanotubes (SWCNTs) generated in a primary manufacturing plant. It also compared various strategies of exposure monitoring.
Methods: A 6-day measurement protocol was scheduled (D1-D6) including both (i) quasi-personal monitoring with an array of direct reading instruments (DRIs) and (ii) offline electron microscopy analyses of surface and breathing zone filter-based samples.
Transmission electron microscopy (TEM) is a powerful and efficient tool for the analysis of asbestos fibers. Although this analysis technique is common and several standard methods exist for asbestos analysis, questions remain about the optimal conditions to be used. Because asbestos fibers are relatively sensitive to the electron beam, it is important to better understand the phenomena of damage in order to avoid them.
View Article and Find Full Text PDFDamage to asbestos fibers by the transmission electron microscope (TEM) electron beam is a known limitation of this powerful method of analysis. Although it is often considered only in terms of loss of crystallinity, recent studies have shown that the damage may also change the elemental composition of fibers, thus causing significant identification errors. In this study, the main objective was to assess whether temperature is a factor influencing damage to asbestos fibers and, if so, how it can be used to minimize damage.
View Article and Find Full Text PDFAsbestos amosite fibers were investigated to evaluate the damage caused by a transmission electron microscope (TEM) electron beam. Since elemental x-ray intensity ratios obtained by energy dispersive x-ray spectroscopy (EDS) are commonly used for asbestos identification, the impact of beam damage on these ratios was evaluated. It was determined that the magnesium/silicon ratio best represented the damage caused to the fiber.
View Article and Find Full Text PDFObjective: Controversy surrounds the safety of cervical spine manipulation. Ischemic stroke secondary to cervical spine manipulation is a hypothesized adverse event. In Canada, the seriousness of these events and their perceived association to cervical spine manipulation has led some members of the public to call for a ban of the procedure.
View Article and Find Full Text PDFThis study assessed the contribution of electron microscopy to the characterization of nanoparticles and compared the degree of variability in sizes observed within each stage when sampled by two cascade impactors: an Electrical Low Pressure Impactor (ELPI) and a Micro-Orifice Uniform Deposit Impactor (MOUDI). A TiO(2) nanoparticle (5 nm) suspension was aerosolized in an inhalation chamber. Nanoparticles sampled by the impactors were collected on aluminum substrates or TEM carbon-coated copper grids using templates, specifically designed in our laboratories, for scanning and transmission electron microscopy (SEM, TEM) analysis, respectively.
View Article and Find Full Text PDFBeryllium is used in a wide variety of industries. Chronic beryllium disease is the most common occupational disease among workers following exposure to Be. The objective of this study was to determine the immunologic effects of two different particle sizes of Be metal, <2.
View Article and Find Full Text PDFAluminum smelters produce in excess thousand of tons of spent pot lining (SPL) each year. CAlSiFrit technology is a recycling process in which spent pot lining (SPL) is recovered and transformed into commercial value-added products. Since SPL contains beryllium (Be), exposures encountered by workers may result in adverse effects.
View Article and Find Full Text PDFThe problems associated with detecting and characterizing beryllium (Be) particles in industrial samples from Québec were addressed in the companion article (Rouleau et al., 2005). The present study is a continuation of the work aimed at redefining the current occupational exposure level for beryllium.
View Article and Find Full Text PDFChemical and physical characterizations of beryllium (Be) particles found in settled dust samples from four industries based in Québec were attempted using a variety of analytical methods. Bulk particle chemistry was determined using inductively coupled plasma-mass spectrometry (ICP-MS), graphite furnace atomic absorption spectrometry (GFAAS), and instrumental neutron activation analysis (INAA). Time-of-flight secondary-ion mass spectrometry (TOF-SIMS), transmission electron microscopy, scanning electron microscopy, energy-dispersive spectroscopy, x-ray diffraction (XRD), electron energy loss spectrometry (EELS), and Auger microscopy were used to characterize physicochemical properties of particles.
View Article and Find Full Text PDFThe use of methylcyclopentadienyl manganese tricarbonyl (MMT) in unleaded gasoline has given rise to numerous debates on the potential public health risk associated with manganese emissions. In fact, combustion products are mainly Mn phosphate, Mn sulfate, and Mn phosphate/sulfate mixture. Our research group did several inhalation studies in order to assess the toxicity of each Mn species.
View Article and Find Full Text PDFAJNR Am J Neuroradiol
August 1997
Purpose: To evaluate the safety and efficacy of endovascular treatment of ophthalmic segment aneurysms with Guglielmi detachable coils (GDCs), as well as the primary indications for such treatment.
Methods: We conducted a prospective study of 26 patients with 28 aneurysms of the ophthalmic segment in whom treatment with GDCs was attempted. Anatomic results were measured by statistical analysis of variance for such factors as age, sex, presence of subarachnoid hemorrhage, anatomic type (ophthalmic or superior hypophyseal), size of aneurysmal sac, and width of aneurysmal neck.
The surgical treatment of basilar bifurcation aneurysms is difficult and the need for an alternative approach is frequently stated. To assess the efficacy and safety of endovascular treatment of aneurysms located at the basilar bifurcation, the authors prospectively studied angiographic results, clinical results, and complications in 31 patients treated with Guglielmi detachable coils (GDCs). Patients treated acutely after subarachnoid hemorrhage (SAH) were graded according to the Hunt and Hess classification and clinical outcome was determined at 1- and 6-month intervals according to the Glasgow Outcome Scale (GOS).
View Article and Find Full Text PDFThis research measured the exposure of two groups of workers to respirable and total manganese (Mn) and characterized the Mn particles emitted from an automobile tailpipe. The exposure of 20 office workers and 9 taxi drivers in Toronto to total airborne Mn and respirable Mn was measured over a 7-day period, 24 hours per day. Subjects were asked to wear two pumps (one included a size-selective cyclone that collected the respirable particles), and two battery chargers were supplied to each person so that the pump batteries could be recharged overnight while sampling continued.
View Article and Find Full Text PDFThe formability of galvanneal steel sheets used in the automotive industry is influenced by the presence and distribution of brittle and difficult to distinguish Zn-Fe intermetallics in the coating. Characterization of these intermetallics requires a high spatial resolution technique such as analytical transmission electron microscopy (ATEM). Sample preparation by ion milling is impossible due to iron redeposition, and traditional ultramicrotomy using water affects the coating chemistry.
View Article and Find Full Text PDFJ Electron Microsc Tech
October 1989
This article has been written for experimenters who are beginning to work with convergent beam electron diffraction patterns (CBED). The indexing of the higher-order Laue zone (HOLZ) lines inside the central spot of a CBED pattern is the first step towards studying variations in lattice parameter and three-dimensional (3D) symmetry. To index the HOLZ lines one must construct and index the HOLZ, find its interplanar spacing and the location of its projection on the zero order Laüe zone (ZOLZ) for a given zone axis, and finally find the radius of the HOLZ ring.
View Article and Find Full Text PDFInt Urol Nephrol
December 1986
The effect of 3 hydroxamic acid derivatives on urease-induced crystalluria was studied in vitro. Acetohydroxamic acid is more effective than salicylhydroxamic and gentisohydroxamic acids in inhibiting the kinetic of urease enzymatic reaction and in retarding the formation of struvite and apatite. Crystal deposits studied by scanning electron microscope (S.
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