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The focal article (Reynolds, McCauley, Tsacoumis, and the Jeanneret Symposium Participants, 2018) reviewed and discussed the challenges, practices, and opportunities for the assessment and development for senior leaders. They summarized a set of accepted wisdom for assessing senior leaders in the areas of assessment criteria, contexts, and implementation, and meanwhile, pointed out what should be explored and done in the future. One of the central premises of the focal article seems to be built on the assumption that organizations may have sufficient resources to follow the accepted wisdom to ensure the quality and effectiveness of assessment and development for senior leaders. In addition, most, if not all, of the research findings summarized and discussed in the focal article may be based on the studies under the context of established companies. Hence, whether the implications and suggestions from the focal article can generalize to small enterprises remain an open question. For example, a typical small enterprise in the United States is a company capitalized with about $25,000 (Shane, 2009). Most of these enterprises are highly centralized, have negative cash flow, and have troubles in securing cash and in obtaining customer acceptance (Rutherford & Buller, 2007). Thus, these companies may not be able to follow the accepted wisdom as recommended in the focal article. We realize that some small businesses and start-ups are extremely well funded, so our following comments apply only to those small enterprises with scarce resources.
Several lines of evidence suggest that the x-ray spectra of quasars are not simple, exact power laws: 1. when Wilkes and Elvis (1987) analyzed quasars as power laws they found an absorption less than that due to our galaxy; 2. The mean 0.3 to 3.5 keV spectral index is steeper than the mean for the 2 to 20 keV range; 3. although several lines of evidence argue that AGN provide a significant portion (perhaps all) of the x-ray background, the diffuse background spectrum does not agree with the x-ray power-law indices measured for quasars or Seyfert galaxies. Schwartz and Tucker (1988) have suggested that all the above conflicts are reconciled if the slope in the Log(flux density) vs. Log(energy) plot flattens continuously with increasing energy. In this paper we utilize one particular parameterization suggested for the flux density, which we call the “log-slope” model:
where f is the flux density, K a normalization parameter which is not of interest here, and a and b are the two parameters of our fit.
In this paper, the dynamical behavior and stability of hanging micropipes conveying fluid with pinned-free boundary conditions are investigated. For a pinned-free rigid micropipe, the dynamical system is found to be stable for various flow velocities. Particular emphasis is placed on the effects of flow velocity, mass ratio and gravity on the dynamics and flutter instability of flexible micropipe system with pinned-free boundary conditions. The governing equations for flexible micropipes are discretized using the differential quadrature method (DQM), yielding a generalized eigenvalue problem which is then solved for various flow velocities, mass ratios and gravity parameters. It is shown that, with increasing flow velocity, the flexible micropipe with pinned-free boundary conditions is stable until it becomes unstable via a Hopf bifurcation leading to flutter. The system may lose stability first in the second or third mode, mainly depending on the selected value of mass ratio. The existence of mode exchange between the second and third modes is possible. The gravity parameter of positive values causes additional restoring force and hence enhances the stability of the micropipe system; however, it can generate the complexity of stability diagrams.
We investigated the first presence of qnrA among Shigella sonnei clinical isolates in Jiangsu Province, China. The qnrA-positive isolates coexisted with the mutation in gyrA at codon 83, these isolates were resistant to nalidixic acid and 22·2% (2 of 9) of them were resistant to norfloxacin.
Introduction: The Calgary Stampede is a two-week mass gathering occurring annually in July. Clinicians have anecdotally noted increases in emergency department (ED) and urgent care (UC) visits, especially for complaints related to substance misuse and violence. Our objectives were: 1) to determine if there is an increase in overall visits to EDs and UCs during the Stampede, and 2) to determine if there are increases in presentations related to trauma, violence, or intoxication. Methods: This observational study used prospectively collected administrative data from five EDs and two UCs in Calgary. For the years 2013 to 2016, daily average data during Stampede dates were compared to the data from the 21 days immediately preceding and following the event. Dates were selected to incorporate a similar proportion of weekends and weekdays in the Stampede and non-Stampede periods. The primary outcome was daily average ED and UC utilization. Secondary outcomes included time of arrival, utilization by demographic groups, complaint category at triage, or International Statistical Classification of Diseases, 10th revision (ICD-10) diagnosis. Results: The study period included 263 380 individual ED and UC visits (34 492 Stampede and 228 888 non-Stampede visits). Daily average ED and UC visits increased by 2.1% (p<0.0001) during the Stampede period. Increases in utilization were identified in specific subgroups: male, ambulance arrival, and nighttime arrival between 2000 and 0400 (all p<0.05). The Stampede period saw a marked increase in CTAS 1 visits (16.2%, p<0.01), triage complaints of lacerations (12.4%, p<0.0001) and blunt trauma (19.4%, p<0.0001), and the ICD-10 diagnosis of substance misuse (23.9%, p=0.01). Visits triaged to the minor treatment areas increased by 9.5% (p<0.0001), again most markedly at night (15.3%, p<0.0001).No differences were detected for triage complaints of altered level of consciousness, sexual assault, head or neck injury, limb injury, or social problems. Conclusion: The Calgary Stampede provokes appreciable changes in overall ED and UC utilization, with marked increases in nighttime visits, visits by men, trauma or substance abuse-related complaints, and minor treatment visits. This data may be useful in manpower planning to ensure optimal patient flow and service delivery during mass gatherings.
Deploying resistant cultivars is an economical and essential management method in controlling viral diseases, and there are several mutational resources for tobacco. In the present study, the inoculation of tobacco plants with tobacco viruses was performed in a greenhouse from 2011 to 2014 to identify mutants resistant to tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV). The high-throughput screening included seeding uniformly, transplanting in seedbeds, inoculating by cloth brushes and reporting symptoms based on disease indices. A total of 4000 second generation segregating (M2) mutants of tobacco cultivar Zhongyan100 were screened. Seeds from highly resistant mutant M2 plants were selected and planted separately. The M3 were grown and mutational stability was measured. For TMV, ten highly resistant plants were selected in the M2 generation and the mutation rate was 0·012%. In the M3 generation, there were seven mutants with hereditary high resistance and, according to the results of real-time polymerase chain reaction, the N gene was detected in all seven M3. Two hereditary immune M4 mutants, one of which was a male sterile line, were identified and evaluated in the glasshouse and in the field. For CMV, seven highly resistant plants were selected from the M2 generation and the mutation rate was 0·009%. In the M3 generation, there was one mutant with hereditary high resistance. The results indicate that hereditary mutants may be identified in the M4 generation and back-crossed to wild-type Zhongyan100 to identify anti-viral genes.
In this paper, we introduce a diffuse interface model for describing the dynamics of mixtures involving multiple (two or more) phases. The coupled hydrodynamical system is derived through an energetic variational approach. The total energy of the system includes the kinetic energy and the mixing (interfacial) energies. The least action principle (or the principle of virtual work) is applied to derive the conservative part of the dynamics, with a focus on the reversible part of the stress tensor arising from the mixing energies. The dissipative part of the dynamics is then introduced through a dissipation function in the energy law, in line with Onsager's principle of maximum dissipation. The final system, formed by a set of coupled time-dependent partial differential equations, reflects a balance among various conservative and dissipative forces and governs the evolution of velocity and phase fields. To demonstrate the applicability of the proposed model, a few two-dimensional simulations have been carried out, including (1) the force balance at the three-phase contact line in equilibrium, (2) a rising bubble penetrating a fluid-fluid interface, and (3) a solid particle falling in a binary fluid. The effects of slip at solid surface have been examined in connection with contact line motion and a pinch-off phenomenon.
English ivy (Hedera helix) is an evergreen, perennial vine that was introduced from Europe and Asia and is not endemic in much of the United States. English ivy can be invasive and difficult to control once established. Four similar, but not identical, experiments were conducted in sequence to evaluate selected, POST-applied herbicides for English ivy control. English ivy plants were propagated from cuttings and container-grown to obtain a large population of uniform plants. Aminopyralid and fluroxypyr applied at 1.34 and 0.71 kg ae ha−1, which is more twice the maximum registered rate for either herbicide, were ineffective. Glyphosate and 2,4-D amine were generally more effective, but neither herbicide provided a level of control that could be deemed consistently acceptable. Glyphosate applied at 8.51 kg ae ha−1 (the highest rate evaluated) provided 69, 98, and 89% control in the second, third, and fourth experiments as determined by foliage fresh-weight reduction relative to a nontreated control. Treatment with 2,4-D at 5.60 kg ae ha−1 (the highest rate evaluated) controlled English ivy 28, 98, and 89% in the second, third, and fourth experiments, respectively. Mixtures of 2,4-D and glyphosate were generally no more effective than were the components applied alone. Metsulfuron was the most effective herbicide. Metsulfuron applied at 0.168 kg ai ha−1 controlled English ivy ≥ 97% across the three experiments in which this treatment was included. This treatment also prevented regrowth.
Large electrocaloric (EC) effects in ferroelectric polymers and in ferroelectric ceramics have attracted great attention for new refrigeration development which is more environmental friendly and more efficient and thus could be an alternative to the existing vapor-compression refrigerators which consume large energy and release large amount of green house gas. However in the past, all EC effects investigations have been focused on solid state dielectrics. It is interesting to ask whether a large EC effect can also be realized in dielectric fluids. A dielectric fluid with large EC effect could lead to new design of cooling devices with simpler structures than these based on solid state EC materials, for example, they can be utilized as both the refrigerant and heat exchange fluid. Here we present that a large EC effect can be realized in the liquid crystal (LC) 5CB near it's nematic-isotropic (N-I) phase transition. The LC 5CB possesses a large dielectric anisotropy which can induce large polarization change from the isotropic phase to the nematic phase near the N-I transition. An isothermal entropy change of more than 23 Jkg-1K-1 was observed near 39 oC that is just above the N-I transition.
The advantages and limitations of image guidance systems for endoscopic sinus surgery are unclear. We report our experience and present a meta-analysis of the evidence.
We performed a retrospective analysis of endoscopic sinus surgery procedures performed with versus without image guidance. A total of 355 cases was included. Primary outcomes included complication rates and time to revision surgery. A literature search was conducted to enable identification and analysis of studies of similar comparisons.
Within 1.5 years of the index sinus surgical procedure, the risk of revision surgery was significantly higher for patients treated with non-assisted versus computer-assisted endoscopic sinus surgery (p = 0.001). Meta-analysis did not indicate a reduction in complications or revision surgery procedures with the use of image guidance systems, although the majority of included studies showed a non-significant reduction in revision surgery.
Our study offers some evidence that computer-assisted endoscopic sinus surgery may delay residual disease and reduce the requirement for revision surgery. Although this finding was not borne out in the meta-analysis, the majority of identified studies demonstrated a trend towards fewer revision procedures after computer-assisted endoscopic sinus surgery. This type of surgery may offer other advantages that are not easily measurable.
We studied seasonal patterns of swine hepatitis E virus (HEV) infection in China. From 2008 to 2011, 4200 swine bile specimens were collected for the detection of HEV RNA. A total of 92/2400 (3·83%) specimens in eastern China and 47/1800 (2·61%) specimens in southwestern China were positive for HEV. Seasonal patterns differing by geographical area were suggested. In eastern China, the major peak of HEV RNA prevalence was during March–April, with a minor peak during September–October, and a dip during July–August. In southwestern China, the peak was during September–October and the dip during March–April. The majority of subtype 4a cases (63/82, 76·83%) were detected in the first half of the year, while the majority of subtype 4b cases (26/29, 89·66%) were concentrated in the second half of the year, suggesting that different subtypes contribute to different peaks. Our results indicate that the distribution of HEV subtypes is associated with seasonal patterns.
Transoral rigid laryngoscopy with videostroboscopy is the most practical method to visualise the vocal folds. The optimal topical anaesthesia regimen for transoral rigid laryngoscopy has not yet been established.
To compare patient comfort and compliance with various topical anaesthetics for transoral rigid laryngoscopy.
Each of 10 patients received a random topical administration of either 2 per cent lidocaine gel, 1 per cent tetracaine gel or 1 per cent tetracaine solution, 10 minutes before undergoing rigid laryngoscopy with videostroboscopy. During follow-up laryngoscopies, the agent with the lowest mean visual analogue scale score for discomfort was then used to study the timing of topical anaesthetic application: the agent was given to the patient 5, 10 or 15 minutes before laryngoscopy (with the timing randomly selected).
Compared with lidocaine gel or tetracaine gel, laryngoscopy with topical tetracaine solution was more comfortable. There was a statistically significant difference in discomfort score between the 5 and 10 minute application groups, but not between the 10 and 15 minute groups.
The roles of hydrogen plasma radicals on passivation of several kinds of crystallized poly-Si thin films were investigated using optical emission spectroscopy (OES) combined with Hall mobility, Raman spectra, and absorption coefficient spectra. It was found that different kinds of hydrogen plasma radicals are responsible for passivation of dissimilar poly-Si crystallized by different method. Radicals Hα with lower energy are mainly responsible for passivating the poly-Si crystallized by solid phase crystallization (SPC) whose crystallization precursor was made by plasma enhanced chemical vapor deposition (PECVD). Higher energy radicals H* are more effective in passivating defects left over by Ni in poly-Si crystallized by Metal Induced Crystallization (MIC). The highest energy radicals Hβ and Hγ are needed to passivate the defects in poly-Si crystallized by SPC but whose precursor was made by low pressure CVD (LPCVD).
A technique to improve and accelerate aluminum induced crystallization (AIC) by hydrogen plasma is proposed in this paper. Raman spectroscopy and Secondary Ion Mass Spectrometry of crystallized poly-Si thin films show that hydrogen plasma radicals reduce the crystallization time of AIC. This technique shortens the annealing time from 10 hours to 4 hours and increases the Hall mobility from 22.1 cm2/V·s to 42.5 cm2/V·s. The possible mechanism of AIC assisted by hydrogen radicals will also be discussed.