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Distance from the technology frontier: How could Africa catch-up via socio-institutional factors and human capital?
No full textDrawing on stylized evidences on emerging economies and Sub-Saharan Africa, we ask: why some countries lag while some are fast in catching-up? By considering a tripartite grouping—advanced North, dynamic emerging Southern engines of growth, and laggards in Sub-Saharan Africa—this paper (i) uses the metafrontier approach for measuring the technology gap between the African nations and emerging economies, and (ii) tests the relationship between the technology gap, educational quality, trade openness, and foreign direct investment. We show that knowledge capabilities backed by human development, access to new technology, capacity to absorb new technologies are essential for development success. On the other hand, Africa's poor infrastructure, relatively poor business environment, and lack of human development are the most significant barriers to technology catch-up. Results show that globalization is not merely the means of opening new markets but for achieving higher productivity through technology transfers. Moreover, improved macroeconomic policies and sustained reform, as well as human capital, stronger governance and better investment climate are needed for accelerating the technology catch-up, and to put the African economies on a path to sustainable growth.We benefited immensely from the valuable comments of the participants in the “Learning to Complete: Industrial Development and Policy in Africa Conference at the United Nations University-World Institute of Development Economics Research (UNU-WIDER), 24—25 June, 2013, Helsinki, Finland”. Among the participants, special thanks go to Augustin Fosu, Kunal Sen, and Sajal Lahiri for constructive comments. Comments from two anonymous referees and editors were extremely helpful. The usual absolution applies
Efficacy and Safety of Omega-3 Fatty Acids in Patients Treated with Statins for Residual Hypertriglyceridemia: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial
No full textBackground: Cardiovascular risk remains increased despite optimal low density lipoprotein cholesterol (LDL-C) level induced
by intensive statin therapy. Therefore, recent guidelines recommend non-high density lipoprotein cholesterol (non-HDL-C) as a secondary target for preventing cardiovascular events. The aim of this study was to assess the efficacy and tolerability of omega-3 fatty acids (OM3-FAs) in combination with atorvastatin compared to atorvastatin alone in patients with mixed dyslipidemia.
Methods: This randomized, double-blind, placebo-controlled, parallel-group, and phase III multicenter study included adults
with fasting triglyceride (TG) levels ≥200 and ˂500 mg/dL and LDL-C levels ˂110 mg/dL. Eligible subjects were randomized to
ATOMEGA (OM3-FAs 4,000 mg plus atorvastatin calcium 20 mg) or atorvastatin 20 mg plus placebo groups. The primary effi-
cacy endpoints were the percent changes in TG and non-HDL-C levels from baseline at the end of treatment.
Results: After 8 weeks of treatment, the percent changes from baseline in TG (–29.8% vs. 3.6%, P˂0.001) and non-HDL-C
(–10.1% vs. 4.9%, P˂0.001) levels were significantly greater in the ATOMEGA group (n=97) than in the atorvastatin group
(n=103). Moreover, the proportion of total subjects reaching TG target of ˂200 mg/dL in the ATOMEGA group was significantly
higher than that in the atorvastatin group (62.9% vs. 22.3%, P˂0.001). The incidence of adverse events did not differ between the two groups.
Conclusion: The addition of OM3-FAs to atorvastatin improved TG and non-HDL-C levels to a significant extent compared to
atorvastatin alone in subjects with residual hypertriglyceridemia.This work was financially supported by the Kuhnil Pharmaceutical Co., Ltd. (Seoul, Republic of Korea). The company funder had no role in the study design, in the collection, analysis, and interpretation of data, in the writing of the manuscript, and in the decision to submit the article for publication
Gold Nanodots-Decorated Nickel Hydroxide Nanoflowers for Enhanced Electrochemical Oxygen Evolution Activity
No full textOxygen evolution reaction (OER) is considered a major challenge in the production of efficient electrochemical water splitting devices. To overcome the challenge, the development of inexpensive electrochemical catalysts with high energy conversion efficiencies is vital. Nanohybrids composed of noble metal nanoparticles and transition metal hydroxides often possess catalytically active sites that are beneficial for OER performance. In this study, we report a successful synthesis of Ni(OH)2 nanoflowers with a high degree of crystallinity and uniformity. The as-prepared Ni(OH)2 nanoflowers are employed as templates for effective and controllable loading of Au nanodots to obtain Ni(OH)2@Au nanohybrids. An examination of the OER activity reveals that Ni(OH)2@Au nanohybrids exhibit a considerably lower overpotential (η) value (390 mV) at a current density of 5 mA cm–2 and a smaller Tafel slope (120 mV dec–1) than those of Ni(OH)2 nanoflowers (540 mV and 324 mV dec–1, respectively). The OER enhancement effect is mainly attributed to the decoration of Au nanodots, inducing charge transfer from Ni to Au and thereby stabilizing the Ni species at high oxidation levels. Moreover, the uniform loading of Au nanodots on the anisotropic Ni(OH)2 nanoflowers provides more active interfacial surfaces, which are expedient to OER.This research was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (NRF-2015R1A4A1041631 and NRF-2016R1A2B4009281)
Numerical simulation of a multi-port differential mobility analyzer(MP-DMA) used in a real-time nano-particle sizer (NPS)
No full textIn a recently conducted study, we developed a nano-particle sizer (NPS) that consists of a multi-port differential mobility analyzer (MP-DMA) and two multi condensation particle counters (M-CPCs) for achieving fast measurements of aerosol particles; however, the performance of MP-DMA was not detailed in the study. Therefore, the objective of this study is to perform numerical simulations to obtain the transfer function of each port in the MP-DMA, which is the main component of the NPS. We observed good agreement between the numerically obtained central particle size of each port and the experimental data under the same operating conditions. The transmission probability and resolution of each port were determined and analyzed under various conditions using the transfer function. The findings of this study shall help in understanding the advantages of NPS.This work was supported by the research fund of Hanyang University (HY-2019-P)
From civic to citizenship education: Toward a stronger citizenship orientation in the Ethiopian CEE curriculum
No full textRecent research on Civic and Ethical Education (CEE) in Ethiopia has revealed a need for improvement in a number of areas with regard to the current CEE curricula. These materials are currently oriented to a conservative form of civic education than on citizenship education, whose aims are more progressive. The essential problem identified in the present study is that CEE content does not match the Ethiopian Ministry of Education’s stated goals for CEE, including the promotion of global citizenship. An inductive method was used to categorize themes found in the CEE curricula and textbook, which were analyzed with reference to Tawil’s (2013) framework for education for global citizenship. A concept in textual analysis known as ‘internal critique’ was also utilized to identify inconsistencies in the materials between the stated aims of the CEE program and the textbook content itself. The analysis revealed three main characteristics of the CEE textbooks, namely, an emphasis on sovereignty, patriotism, and responsibility; ambivalence to Ethiopia’s independence from/dependence on wealthier nations, and abstraction in CEE content. This content does only partially match the Ethiopian government’s stated aims for CEE. The findings of this study suggest that the content of the ethical dimension of Ethiopia’s CEE curriculum could be greatly improved through the inclusion of content that reflects an emphasis on citizenship education. Such an approach is more progressive than civic education and promotes a more learner-centered and critical orientation to ethical issues on the part of students within the framework of Global Citizenship Education (GCE)
Modified Smoothing Data Association for Target Tracking in Clutter
No full textTracking an unknown target in noisy environment is difficult especially when the target is maneuvering and has unknown trajectory. Smoother uses measurements from future scans to estimate the target state in past scan. This requires the fusion of forward and backward prediction. However, due to uncertain target motions and low detection probabilities, backward prediction could not associate with forward prediction which results in inequitable fusion pair and thus, smoothing performance could not be improved. To cope with these difficulties, the proposed algorithm modifies the fixed-lag smoothing data association based on the integrated probabilistic data association (IPDA) algorithm and a new algorithm called modified smoothing IPDA (MSIPDA) is developed. MSIPDA utilizes two IPDA filters to obtain forward IPDA (flPDA) track and backward (bIPDA) track estimation in each scan. Each flPDA prediction generates multiple fusion pairs in association with bIPDA multi-track prediction. These fusion pairs are created in the form of components. As a result, multiple smoothing components are formed with their smoothing component data association probabilities for computing MSIPDA track components state estimate. In addition, the smoothing data association probabilities upgrade the forward track which makes the forward track more powerful for target tracking in clutter. The numerical assessment of MSIPDA is verified using simulations. The result shows significant false track discrimination performance in comparison to existing algorithms. (C) 2019 Elsevier Ltd. All rights reserved.This work was supported by Hanwha Systems, South Korea, under the Grant U-17-015
Comparative study of gamma-ray shielding features and some properties of different heavy metal oxide-based tellurite-rich glass systems
No full textTellurite-rich glasses containing Sm3+, Dy3+, and Er3+ ions with nominal chemical composition of 69 TeO2‒10 Bi2O3‒10 BaO‒10 ZnO‒1.0 Sm2O3/1.0 Dy2O3/1.0 Er2O3 (mol%) were fabricated. The gamma radiation attenuation features of the synthesized glasses were compared with two other tellurite glass systems with the chemical composition of 68 TeO2‒(22-x) Bi2O3‒10 ZnO‒ (x) PbO (x = 10, 12, 14, 16 and 18 mol%), and 75 TeO2‒20 B2O3‒5 MxOy (mol%) (MxOy = WO3, Nb2O5, PbO, Nd2O3, Y2O3). The mass attenuation coefficients (μ/ρ) (MAC) were computed from 0.015 MeV to 15 MeV photon energies using the XCOM program. Using the obtained μ/ρ values, effective atomic number (Zeff), electron density (Ne), half-value layer (HVL) and mean free path (MFP) were determined at different photon energies. The results clearly reveal that the MAC depends upon the heavy metals present in the studied glasses, and such addition increases the shielding capabilities of the samples against the gamma radiation. The Zeff and Ne confirmed the shielding effects with a variation in heavy metals content. The HVL and MFP values indicate the potential application in radiation insulation with less probability of interactions with gamma photons in the investigated tellurite glasses. It is found that the HVL or MFP values of the A ‒ C glasses lies in between the HVL or MFP values of the S1 – S5 and the T1 ‒ T5 glasses, respectively. Thus, the synthesized glasses are better shielding materials than the T1 – T5 glasses and possess slightly less gamma-ray shielding capacity than that of S1–S5 glasses.This work was supported in part by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. NRF-2018R1A5A1025137), and in part by the Research Fund of Hanyang University (No. HY-2015-G). The author G.L.N would like to acknowledge the use of the facilities of Universiti Putra Malaysia (UPM), Malaysia. The author (A. Dahshan) gratefully thank the Deanship of Scientific Research at King Khalid University for funding this work through General Research Project under grant number (G.R.P-557-39)
Multi-responsive albumin-lonidamine conjugated hybridized gold nanoparticle as a combined photothermal-chemotherapy for synergistic tumor ablation
No full textHerein, we developed a multifunctional nanoplatform based on the nanoassembly of gold nanoparticles (GNP) conjugated with lonidamine (LND) and aptamer AS1411 (AS-LAGN) as an effective cancer treatment. Conjugating AS1411 aptamer on the surface of the nanoparticle significantly improved particle accumulation in cancer cells via specific affinity toward the nucleolin receptors. In vitro study clearly revealed that laser irradiation-based hyperthermia effect enhanced the chemotherapeutic effects of LND. Combinational treatment modalities revealed significant apoptosis with higher cell killing effect due to increased ROS production and inhibition of cell migration. GNP's ability to convert the excited state photon energy into thermal heat enabled synergistic photothermal/chemotherapy with improved therapeutic efficacy in animal models. Moreover, immunohistochemistry staining assays confirmed the ability of ASLAGN to induce cellular apoptosis/necrosis and ablation in tumor tissues, without causing evident damages to the surrounding healthy tissues. Altogether, this AS-LAGN nanoplatform could be a promising strategy for mitochondria-based cancer treatment.
Statement of significance
We have designed a facile biodegradable multifunctional nanocarrier system to target the mitochondria, the major "power house" of the cancer cells. We have constructed a multifunctional nanoassembly of protein coronated gold nanoparticles (GNP) conjugated with lonidamine (LND) and aptamer AS1411 (ASLAGN) as an effective combination of phototherapy with chemotherapy for cancer treatment. The LND was conjugated with albumin which was in turn conjugated to GNP via redox-liable disulfide linkage to generate oxidative stress and ROS to kill cancer cells. GNP's ability to convert the excited state photon energy into thermal heat enabled synergistic photothermal/chemotherapy with improved therapeutic efficacy in animal models. Consistently, AS-LAGN showed enhanced antitumor efficacy in xenograft tumor model with remarkable tumor regression property. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.This research was supported by a grant from the National Research Foundation of Korea (NRF), funded by the Korea government (MSIP) (No. 2018R1A2A2A05021143 and 2018R1D1A1A02085586), and by the Medical Research Center Program (2015R1A5A2009124 and 2018R1A5A2025272) through the NRF funded by MSIP
Focused ion beam-induced displacive phase transformation from austenite to martensite during fabrication of quenched and partitioned steel micro-pillar
No full textWe report evidence of a displacive phase transformation from retained austenite to martensite during preparation of quenched and partitioned steel micro-pillars by using a focused ion beam (FIB) technique. The BCC phase produced by the FIB damage was identified as martensite. The invariant-plane strain surface relief associated with the martensitic transformation was observed in the retained austenite phase immediately after a FIB scan of the surface with the Ga+ ion beam. Use of a low acceleration voltage appears to lower the probability of the phase transformation, while a decrease of the acceleration voltage will result in an increase of the total milling time required to prepare a micro-pillar. This report addresses challenges related to the preparation of austenite micro-pillars by a conventional FIB technique. Published by Elsevier B.V
Customer Response Toward Employees’ Emotional Labor in Service Industry Settings
No full textIn the current study, we develop and test a moderated mediation model that explores the mechanisms that underlie the influence of employees' emotional labor on customer loyalty by considering affective reactions and cognitive appraisals simultaneously and illustrating moderating factors that alter their effectiveness. A sample of 259 individuals from across the United States over 20 years old were recruited on Amazon's Mechanical Turk to participate in the survey. Our emotions as social information based model clarifies the distinct roles of customers' detection of employees' deep acting and surface acting in influencing customers' affective reactions and cognitive appraisals. The current research also reveals that impact of customers' detection of employees' emotional labor on customer outcomes varies as a function of the employees' nonverbal communication