Phase Transition, Microstructures and Electromechanical Properties of BiAlO3-modified Bi0.5(Na,K)0.5TiO3 Lead-free Piezoelectric Ceramics

Aman Ullah,이선영,이해준,황학인,Ali Hussain,이재신,김일원,안창원 한국물리학회 2010 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.57 No.41

Lead-free piezoelectric (1 - x)(Bi0.5(Na0.75K0.25)0.5TiO3)-xBiAlO3 (BNKT25-BA, 0 ≤ x ≤ 0.10)ceramics were synthesized using a conventional solid state reaction method. The incorporation of BA into the BNKT25 lattice was investigated by using X-ray diffraction (XRD), ferroelectric characterizations and electric-field-induced strain behavior. X-ray diffraction revealed a pure perovskite phase for x ≤ 0.050. A phase transformation from tetragonal to pseudocubic was observed at x =0.050. The polarization hysteresis loops of the BNTK25-BA ceramics indicate that the addition of BA significantly disrupts the ferroelectric order of BNKT25 ceramics. The destabilization of the ferroelectric order is accompanied by an enhancement of the unipolar strain. In particular, a large electric-field-induced strain (S = 0.29%) and a normalized strain (d*33 = Smax/Emax = 484 pm/V)were observed at x = 0.025, near the tetragonal-pseudocubic phase boundary. These results suggest that the BNKT25-BA system is a promising candidate for lead-free electromechanical applications.

Suitability of tomato leaves for larval development of Potato Tuber Moth, Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae)

Aman Dekebo,Sunil Aryal,정철의 한국곤충학회 2019 Entomological Research Vol.49 No.6

The potato tuber moth (PTM) is an important pest of the potato plant and its tuber. With the expansion of its geographic range, the PTM could be potential threat to the tomato (Solanum lycopersicum L.), a congeneric species of the potato. To assess that risk, we tested larval feeding and development of PTM on leaves of five cultivated tomato varieties namely Moneymaker, Campari, Ailsa Craig, LA3475, E6203 and one wild tomato variety S. pimpinellifolium. PTM larvae accepted all tested plant leaves and developed into adults. Larval development was fastest on the Ailsa Craig variety. Pupae developed fastest on the Moneymaker variety and slowest on LA3475. Host acceptance and survival were highest on Ailsa Craig and lowest on LA3475. The significantly highest male proportion occurred on LA3475 variety. The study showed that PTM could be a potential threat to tomato cultivation which is rapidly increasing in temperate regions owing to climate change.

Chemical interaction of tomato and potato tuber moth mediated by leaf volatiles

Aman Dekebo,Sunil Aryal,Chuleui Jung 한국농약과학회 2018 한국농약과학회 학술발표대회 논문집 Vol.2018 No.10

Olfactometry of adult potato tuber moth, Phthorimaea operculella (Zeller) to tomato leaves volatiles and its larval development on tomato leaves

Aman Dekebo,Sunil Aryal,Chuleui Jung 한국응용곤충학회 2018 한국응용곤충학회 학술대회논문집 Vol.2018 No.04

The potato tuber moth (PTM) is an oligophagous insect pest on solanaceous crops. Potato tuber is regarded as the main host of PTM but it can also feed, develop and reproduce on other solanaceous crops such as tomato. We tested adult olfactory behavior and larval development on 5 cultivated tomato varieties namely Money maker, Campari, Ailsa craig, LA 3475 (M82) and E-6203, and one wild species, S. pimpinellifolium. Tomato leaf hydro-distilled oils of Money maker, Campari, Ailsa craig, S. pimpinellifolium and E-6203 leaves showed strong attractiveness for mated adult PTM of both sexes (> 70%) in two-armed bioassay. LA 3475 (M82) oil showed repulsive response (83.7% for males and 87.3% for females). GC-MS analysis of the hydro-distilled oils of all tomato leaves contain the fatty acid n-hexadecanoic acid (Palmitic acid) as a major compound with relative percentage as S. pimpinelifollium (32.1%) > E-6203 (26.5%) > money maker (26.1%) > LA-3475 (16.3%) > Campari (15.0%) > Ailsa craig (10.4%). LA 3475 consists of (1-hexyltetraecyl)cyclohexane (10.5%) as the second major compound which was absent in all other tomato varieties. In no choice test, PTM larvae showed highest developmental performances such as number of mines, headcapsule size, pupal weight and survival in Ailsa craig, and lowest in LA 3475. In choice test, similar results were observed. This study indicates the leaf volatile of n-hexadecanoic acid might be responsible for PTM attractiveness and (1-hexyltetraecyl)cyclohexane for repulsiveness. And varieties of tomato leaves could support suitable nutritional contents to PTM, posing pest potential in the future where higher exposure is expected.

Olfactory responses of adult Potato Tuber Moth, Phthorimaea operculella (Zeller) measured by attraction relative to the tomato leaf volatiles

Aman Dekebo,Sunil Aryal,정철의 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.2

The potato tuber moth (PTM) is an oligophagous herbivore and a severe pest of solanaceous crops in many countries of the world. Previously, we reported host expansion and damage potential of PTM on tomato, a congeneric crop of potato. Here we tested adult olfactory behaviour of PTM to leaves of five different cultivated tomato varieties including Moneymaker, Campari, Ailsa craig, LA3475 and E6203, and one wild species, Solanum pimpinellifolium. Tomato leaf hydro-distilled oils of Moneymaker, Campari, Ailsa craig, S. pimpinellifolium and E6203 showed strong attractiveness and LA3475 exhibited repulsiveness for adult PTM of both sexes in two-armed bioassays. Volatiles of Moneymaker, Campari, Ailsa Craig, S. pimpinellifolium and E6203 showed attractiveness for mated adult PTM of both sexes (> 70%). The extracted oil of all tomato leaves contains monoterpenes, sesquiterpenes, diterpenes and C 6 alcohols as well as other components. Phytol is one of the common and major compounds in all tomato varieties. Phytol showed weak attractiveness: 60.8–63.6% and 57.6–60.6% for male and female PTM, respectively when tested at concentrations of 0.1–10 mg/mL. Therefore, the attractiveness of tomato leaf volatiles might be due to synergistic effects of plant volatile mixtures. Identification PTM attractant volatile in tomato leaf is important in its control in environmentally friendly manner.

IS PUBLIC-PRIVATE PARTNERSHIP AN OPTIMAL MODE OF PROVISION OF INFRASTRUCTURE?

AMAN A. BARA,BIDISHA CHAKRABORTY 중앙대학교 경제연구소 2019 Journal of Economic Development Vol.44 No.1

The present paper considers a closed economy model with infrastructure service which is an excludable, impure public good, e.g. metro railway service, electricity service, and telephone service etc. The physical capital required by infrastructure sector is provided by public-private partnership. Public and private investment may be complementary or substitute to each other in infrastructure production. We assume government runs a balanced budget. We find there exists unique, saddle path stable growth rate in both the cases. We find that PPP model is optimal in the provision of infrastructure no matter public capital and private capital are a substitute or complementary to each other. But, PPP solution is not growth maximizing in case of substitute relationship between the public capital and private capital. It also makes a comparative study of decentralized economy and command economy. We find that in case of substitute relationship between private capital and public capital, command economy growth rate is higher than the competitive economy growth rate but in the case of complementary relationship between two, command economy growth rate may not be higher than the competitive economy growth rate.

Strategic Alliance within the Sugar Industry of Pakistan: A Resource Dependence Perspective

AMAN, Rameesha,KHAN, Abdul Rehman Korea Distribution Science Association 2021 Asian journal of business environment Vol.11 No.4

Purpose: This paper uses the resource-dependency theory to present the case of the Pakistan sugar industry to highlight how the industry uses a strategic alliance to gain a powerful bargaining position over its critical dependencies. The case of the Pakistan sugar industry is well-known and it is common knowledge that the alliance or the cartel within it is responsible for frequent price hikes and sugar supply shortages in the country. Research design, data and methodology: We use a case study, qualitative document analysis design to trace how the alliance overcomes its various dependencies, and in doing so, how does it harm various stakeholder interests. Results: This paper finds that the sugar industry alliance maintains its bargaining power by manipulating sugar supply through horizontal alliances, political affiliations, underselling and under-reporting sugar stocks, purchasing sugarcane from the black market, and by gaining billions of rupees in export subsidies by hoarding stock and using its political connections. Conclusion: The paper concludes by providing a summary of the measures which the government has taken to curb this anticompetitive conduct; the most important of which is the removal of protectionist measures for sugar trade and allowing market forces to control the demand and supply of sugar in the local market.

Insect fatty acids: A comparison of lipids from three Orthopterans and Tenebrio molitor L. larvae

Aman Paul,Michel Frederich,Rudy Caparros Megido,Taofic Alabi,PriyankaMalik,Roel Uyttenbroeck,Frederic Francis,Christophe Blecker,Eric Haubruge,Georges Lognay,Sabine Danthine 한국응용곤충학회 2017 Journal of Asia-Pacific Entomology Vol.20 No.2

In order to explore some potential insect sources of food lipids, the lipid compositions of three Orthopterans (Acheta domesticus, Conocephalus discolor and Chorthippus parallelus) were analyzed and compared with those of Tenebrio molitor larvae. A. domesticus, Co. discolor, Ch. parallelus and T. molitor larvae were found to contain approximately 15%, 13%, 10% and 32% lipids on dryweight, respectively. The lipids fromthree Orthopterans contain much higheramounts of essential fatty acids than those of T.molitor larvae. The twoOrthopterans of the suborder Ensifera i.e., A. domesticus and Co. discolor contain linoleic acid inmajor quantities,while Ch. parallelus of the suborder Caelifera, contain α-linolenic acid in major quantities. The consumption of linoleic and α-linolenic fatty acid is linked with numerous health promoting effects. The factors that contribute to differences in fatty acid profiles of these insects are being discussed. At last the nutritional parameters including polyunsaturated to saturated and omega 6 to omega 3 fatty acid ratios of these insect lipids are also being discussed to understand the potential role of these lipids in human nutrition.

Repellency of essential oil of Andong South Korean propolis against small hive beetle and potato tuber moth

Aman Dekebo,KesatebrhanHaile,Sunil Aryal,Hong Seokmin,Chuleui Jung 한국응용곤충학회 2017 한국응용곤충학회 학술대회논문집 Vol.2017 No.10

The potato tuber moth, Phthorimaea operculella (Zeller), is a ubiquitous pest on potatoes, tobacco, tomato and othercrops. The small hive beetle (SHB), Aethina tumida Murray, is a pest of European honeybees (Apis mellifera L.) in severalcountries in the world. Propolis is a balm-like substance collected from plants by bees. Its chemical composition variesand depends mainly on the flora in the region in which it is collected as well as the bee species. Hitherto biologicalproperties and the chemical composition of the essential oil extracted from propolis of Korean origin are unknown. Inthis study, while searching for an environmentally friendly method to control these pests we evaluated the repellent effectsof essential oil of propolis collected from Bee Lab of Andong National University and found that it possess repellentactivity against both small hive beetle and potato tuber moth. Moreover, a total of 171 constituents of the oil were identifiedof which 6 were major compounds using GC/MS analysis. We also compared the chemical composition of this oil withthose from 2 Ethiopian regions.

Anomalies of the Healthcare Sector Using Workplace Safety and Job Satisfaction: A Case Study of Pakistan

AMAN-ULLAH, Attia,AZIZ, Azelin,IBRAHIM, Hadziroh Korea Distribution Science Association 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.3

This study aims to investigate the impact of workplace safety on doctors' retention and turnover intention along with job satisfaction as the mediator. A questionnaire-based survey was conducted with 394 medical doctors working in thirty-five hospitals in Pakistan using a structural equation modeling. Results of the study showed that: 1) workplace safety has a significant positive relationship with employee retention; 2) workplace safety has a significant negative relationship with turnover intention; 3) workplace safety has a significant positive relationship with job satisfaction; 4) job satisfaction has a significant positive relationship with employee retention; 5) job satisfaction has a significant positive relationship with turnover intentions; 6) job satisfaction mediates between workplace safety and employee retention; while 7) job satisfaction failed to mediate between workplace safety and turnover intentions. The findings of the study suggest that in a fear-free and safe environment, employees' chance to stay will increases. The study also suggests that dissatisfied employees do not need to leave the organization. There can be other factors that can be explored in future studies. This study also provides a practical implication for the doctors' low retention and high turnover, specifically in the healthcare sector of Pakistan by providing guidelines to the human resource executives to focus on the strategic implementation of workplace safety.