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WAGE VOLATILITY AND CHANGING PATTERNS OF LABOR SUPPLY
No full textOver the past few decades, the skilled-unskilled hours differential for U.S. men increased when the skill premium rose sharply, in contrast with dominant income effects. Based on PSID data, we show that over the 1967-2000 period, skilled men experienced a three times larger increase in wage volatility than unskilled men. With the rise in wage volatility, our general equilibrium incomplete markets model generates a 2.7 hours increase in the hours differential whereas it increased by 1.4 hours in the data. We find that hours adjustments are important for self-insurance in the short run, whereas precautionary savings play a crucial role eventually
Comparison of 16S rDNA Next Sequencing of Microbiome Communities From Post-scalder and Post-picker Stages in Three Different Commercial Poultry Plants Processing Three Classes of Broilers
No full textPoultry processing systems are a complex network of equipment and automation systems that require a proactive approach to monitoring in order to protect the food supply. Process oversight requires the use of multi-hurdle intervention systems to ensure that any undesirable microorganisms are reduced or eliminated by the time the carcasses are processed into final products. In the present study, whole bird carcass rinses (WBCR) collected at the post-scalder and post-picker locations from three different poultry processing facilities (Plant A: mid-weight broiler processing, B: large-weight broiler processing, C: young broiler (Cornish) processing) were subjected to next generation sequencing (NGS) and microbial quantification using direct plating methods to assess the microbial populations present during these stages of the poultry process. The quantification of aerobic plate counts (APC) and Enterobacteriaceae (EB) demonstrated that reductions for these microbial classes were not consistent between the two sampling locations for all facilities, but did not provide a clear picture of what microorganism(s) may be affecting those shifts. With the utilization of NGS, a more complete characterization of the microbial communities present including microorganisms that would not have been identified with the employed direct plating methodologies were identified. Although the foodborne pathogens typically associated with raw poultry, Salmonella and Campylobacter, were not identified, sequence analysis performed by Quantitative Insights of Microbiology Ecology (QIIME) indicated shifts of Erwinia, Serratia, and Arcobacter, which are microorganisms closely related to Salmonella and Campylobacter. Additionally, the presence of Chryseobacterium and Pseudomonas at both sampling locations and at all three facilities provides evidence that these microorganisms could potentially be utilized to assess the performance of multi-hurdle intervention systems
Dissociation of the ethyl formate radical cation: A computational mechanistic study
No full textWe report a theoretical study of unimolecular dissociation of the ethyl formate radical cation (C2H5OCHO+[rad]). The potential energy surface (PES) of its 14 dissociation reactions, including the formation of CH2CHC(OH)2+, CH2CH2CO+[rad], CH3CHCO+[rad], CH2OCHO+, HOCHOH+, HOCO+, CH3CHOH+, HCO2+, CH2OH+, C2H6+[rad], C2H5+, HCO+, and C2H4+[rad], was determined using G4 calculation. A kinetic analysis using RRKM calculations based on the PES obtained adequately explained the results of previous experiments, suggesting that the dissociation occurred statistically from the electronic ground state. © 2019 Elsevier B.V
Factors Related to Patient Dissatisfaction Versus Objective Failure After Arthroscopic Shoulder Stabilization for Instability
No full textBackground: After arthroscopic stabilization procedures for recurrent anterior shoulder instability, patients are not always satisfied with their shoulder, even when the operation successfully restored stability. The aim of this study was to evaluate the factors associated with subjective patient dissatisfaction after arthroscopic stabilization procedures for recurrent anterior shoulder instability and to compare these factors with those associated with objective surgical failure. Methods: A total of 195 patients who underwent an arthroscopic stabilization procedure for recurrent anterior shoulder instability were included in this study. At the 2-year postoperative visit, subjective patient dissatisfaction was assessed with a 15-point scale. Objective surgical failure was defined as postoperative dislocation or subluxation events requiring revision surgery. Several factors, including age at the first dislocation, age at the time of the operation, presence of an off-track Hill-Sachs lesion, width of the Hill-Sachs lesion, size of the glenoid bone defect, and number of instability events, were recorded. Multivariable linear regression analysis and multivariable logistic regression analysis were performed using a backward stepwise procedure as the variable selection method. Results: Fifteen patients (7.7%) had recurrent instability requiring revision surgery. In the group of 180 patients without surgical failure, the width of the Hill-Sachs lesion (regression coefficient: 0.052, p = 0.011) and number of instability events (regression coefficient: 0.103, p = 0.029) were positively correlated with subjective patient dissatisfaction, whereas concomitant repair of a SLAP (superior labrum anterior-posterior) lesion showed negative correlation (regression coefficient: 20.926, p = 0.004). In the total cohort of patients, objective surgical failure was correlated with the age at the time of the operation (odds ratio [OR]: 0.851, p = 0.042), size of the glenoid bone defect (OR: 1.172, p < 0.001), and number of instability events (OR: 1.147, p = 0.048). Other variables, including an off-track Hill-Sachs lesion or a concomitant remplissage procedure, were not correlated with subjective patient dissatisfaction or objective surgical failure. Conclusions: Factors related to subjective patient dissatisfaction differed from those related to objective surgical failure. For a better understanding of the clinical outcomes after surgery, surgeons should assess the factors that correlate with subjective patient dissatisfaction and objective surgical failure. Level of Evidence: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence
Accelerated Development of Hippocampal Neurons and Limited Adhesion of Astrocytes on Negatively Charged Surfaces
No full textThis work examines the development of primary neurons and astrocytes on thoroughly controlled functional groups. Negatively charged surfaces presenting carboxylate (COO-) or sulfonate (SO3-) groups prove beneficial to neuronal behavior, in spite of their supposed repulsive electrostatic interactions with cellular membranes. The adhesion and survival of primary hippocampal neurons on negatively charged surfaces are comparable to or slightly better than those on positively charged (poly-D-lysine-coated) surfaces, and neuritogenesis and neurite outgrowth are accelerated on COO- and SO3- surfaces. Moreover, such favorable influences of the negatively charged surfaces are only seen in neurons but not for astrocytes. Our results indicate that the in vitro developmental behavior of primary hippocampal neurons is sophisticatedly modulated by angstrom-sized differences in chemical structure or the charge density of the surface. We believe that this work provides new implications for understanding neuron-material interfaces as well as for establishing new ways to fabricate neuro-active surfaces
Noncontrast Magnetic Resonance Angiography for the Diagnosis of Peripheral Vascular Disease
No full textContrast-enhanced magnetic resonance angiography (MRA) provides excellent assessment of the peripheral arterial vasculature and is considered an important adjunctive diagnostic modality for the assessment of peripheral arterial disease. However, given the high prevalence of chronic kidney disease in patients with peripheral arterial disease, the association of gadolinium contrast media with nephrogenic systemic fibrosis, and recent concern with consequences of long-term deposition of gadolinium in the brain, there has been a renewed interest in noncontrast MRA approaches. Recent improvements in pulse sequences combined with instrumentation have facilitated the development of newer noncontrast MRA sequences that provide high spatial resolution, allowing the evaluation of distal (infrageniculate and pedal) vessels of importance in patients with critical limb ischemia. Further, many of these sequences are time efficient and versatile, allowing rapid evaluation of the entire lower extremity vasculature. In this comprehensive review, we outline historic techniques and compare these with newer approaches such as quiescent interval slice-selective MRA, 3-dimensional fast spin echo, and velocity-sensitive MRA that are emerging as an alternative to computed tomographic angiography or digital subtraction angiography for the evaluation of lower limb arteries in patients with peripheral arterial disease. Technical details and applications in clinical practice will be discussed
Large effect of metal substrate on magnetic anisotropy of Co on hexagonal boron nitride
No full textWe combine x-ray absorption spectroscopy (XAS), x-raymagnetic circular dichroism (XMCD) and x-ray magnetic linear dichroism (XMLD) data with first principles density functional theory (DFT) calculations and amultiorbital many-body Hamiltonian approach to understand the electronic and magnetic properties of Co atoms adsorbed on h-BN/Ru(0001) and h-BN/Ir(111). The XAS line shape reveals, for both substrates, an electronic configuration close to 3d(8), corresponding to a spin S = 1 Magnetic field dependent XMCD data show large (14 meV) out-of-plane anisotropy on h-BN/Ru(0001), while it is almost isotropic (tens of mu eV) on h-BN/Ir(111). XMLD data together with both DFT calculations and the results of the multiorbital Hubbard model suggest that the dissimilar magnetic anisotropy originates from different Co adsorption sites, namely atop Non h-BN/Ru(0001) and 6-fold hollow on h-BN/Ir(111)
A chromenone analog as an ATP-competitive, DNA non-intercalative topoisomerase II catalytic inhibitor with preferences toward the alpha isoform
No full text5-Hydroxy-2-phenyl-7-(thiiran-2-ylmethoxy)-4H-chromen-4-one (compound 52) was found as a DNA non-intercalative topo II specific catalytic inhibitor by targeting its ATP-binding domain. Showing changes in interaction with Mg2+, it exhibited highly selective properties against the alpha -isoform with less toxicity, unlike other topo II poisons, such as etoposide
Unique health identifiers for universal health coverage
No full textIdentifying everyone residing in a country, especially the poor, is an indispensable part of pursuing universal health coverage (UHC). Having information on an individuals' financial protection is also imperative for measuring the progress of UHC. This paper examines different ways of instituting a system of unique health identifiers that can lead toward achieving UHC, particularly in relation to utilizing universal civil registration and national unique identification number systems. Civil registration is a fundamental function of the government that establishes a legal identity for individuals and enables them to access essential public services. National unique identification numbers assigned at birth registration can further link their vital event information with data collected in different sectors, including in finance and health. Some countries use the national unique identification number as the unique health identifier, such as is done in South Korea and Thailand. In other countries, a unique health identifier is created in addition to the national unique identification number, but the two numbers are linked; Slovenia offers an example of this arrangement. The advantages and disadvantages of the system types are discussed in the paper. In either approach, linking the health system with the civil registration and national identity management systems contributed to advancing effective and efficient UHC programs in those countries. © 2019 The Author(s)
Long-Term Symptoms of Mobile Phone Use on Mobile Phone Addiction and Depression Among Korean Adolescents
No full textThis study aimed to compare the mean scores of mobile phone use, mobile phone addiction, and depressive symptoms at three-time points among Korean adolescents according to gender and to examine the differences in the long-term relationships among the three abovementioned variables between Korean boys and girls in a four-year period. Data for 1794 adolescents (897 boys and 897 girls) were obtained from three waves of the second panel of the Korean Children and Youth Panel Survey. Multigroup structural equation modeling was used for data analyses. The study findings showed that at each of the three-time points, Korean girls tended to use their mobile phones more frequently and were at a higher risk of mobile phone addiction and depressive symptoms than Korean boys. Significant changes were observed in the longitudinal relationships among phone use, mobile phone addiction, and depressive symptoms in Korean adolescents across time periods, but no gender differences were found in the strengths of these relationships. These findings contribute to expanding the knowledge base of mobile phone addiction and depressive symptoms among Korean adolescents