• Title/Summary/Keyword: persistence-

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Studies on Persistence of Pesticides in Soils and Crops under Polyethylene Film Mulching Culture II. Effect of Polyethylene Film mulching on Weed Emergence, Growth and Yield of Red pepper, Peanut and Sesame (폴리에틸렌 멀칭재배(栽培) 시(時) 농약(農藥)의 토양(土壤) 및 작물체중(作物体中) 잔류(殘留)에 관한 연구(硏究) 제(第) 2 보(報) 폴리에틸렌 멀칭이 잡초발생(雜草發生), 고추, 땅콩, 참깨의 생육(生育) 및 수량(收量)에 미치는 영향(影響))

  • Ryang, H.S.;Moon, Y.H.;Kim, N.E.;Lee, J.H.
    • Korean Journal of Weed Science
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    • v.7 no.3
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    • pp.306-315
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    • 1987
  • In the red pepper field under polythylene film mulching(P.E.-mulching) culture, the weed emergence was completely inhibited by black P.E.-mulching. The emergence in clear P.E.-mulching decreased 90% compared to that in non-mulching. Weeding effect was high in the order of pendimethalin, diphenamid, alachlor and napropamide. The effect of herbicides was higher in clear P.E.-mulching than in non-mulching. Plant height and number of branches increased in the order of clear P.E.-, black P.E.-mulching, while the yield between black P.E.- and clear P.E.-mulching was not different. The herbicides had no effect on the growth and yield. In the peanut field, weed emergence was 80% lower in clear P.E.-mulching than in non-mulching. Weeding effect was excellent in the plot applied with alachlor, napropamide and diphenamid. The total number of branches, main stem height and shoot weight were 2.0, 1.7 and 2.4 times greater in clear P.E.-mulching than in non-mulching, respectively. Peanut yield was about 38% higher under clear P.E.-mulching than under non-mulching. The herbicides had no effect on the growth and yield. In the sesame field, rate of weed emergence was 10 times lower in clear P.E.-mulching than in non-mulching. Weeding effect of alachlor, napropamide and diphenamid was higher under clear P.E.-mulching than under non-mulching. Germination percentage of sesame greatly decreased in non-mulching compared with in clear P.E.-mulching. The germination was inhibited by the treatment of herbicides. The inhibition effect was increased in the order of alachlor, napropamide, and diphenamid. The initial crop injury in treatment of herbicides was greater in non-mulching than in clear P.E.-mulching. The crop recovered from the injury and exhibited regrowth in clear P.E.-mulching except the alachlor treatment, but there was no recovery in non-mulching. There was no significant difference yield between herbicide treatment and hand weeding in non-mulching. Also, no significant difference was obseorbed between napropamide and diphenamid treatment and hand weeding in clear P.E.-mulching.

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Effect of Alachlor Herbicide and Transparent Polyethylene Film Mulching on Growth and Yield of Peanuts (Alachlor와 P.E. 피복(被覆)이 땅콩의 생육(生育)과 수량(收量)에 미치는 영향(影響))

  • Lee, S.S.;Kang, K.H.;Back, J.H.;Lee, K.H.;Jung, S.H.;Choi, D.W.
    • Korean Journal of Weed Science
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    • v.4 no.1
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    • pp.79-87
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    • 1984
  • Herbicidal effects of alachlor to peanuts were observed under different formulations (granule containing 5.0% a.i. and emulsifiable concentrate containing 43.7% a.i.) and levels (granule with 3 and 6kg/l0a and emulsion with 300㏄/l0a) with the transparent polyethylene (P.E.) film mulching. Formulations and levels of alachlor did not affect emergence ratio, time of emergence and flowering, and early growth of peanuts such as the number of leaves and branches, length of branches; and shoot dry weight at 20 and 40 days after planting, but early growth was enhanced by P.E. film mulching. At harvest, weed dry weight was positively correlated with length of branches, but negatively correlated with the number of branches and shoot dry weight. Acalyphu australis and Chenopodium album were not effectively controlled by the application of alachlor and growth of C. album was retarded under P.E. film mulching. Portulaca oleracea and Digitaria sanguinalis were effectively controlled by alachlor, but they were not affected by P.E. film mulching. At harvest, D. sanguinalis, A. australis, and Echinochloa crus galli were predominant weeds in all treatments; persistence of alachlor may not be long enough to control even sensitive weeds to alachlor such as D, sanguinalis in the field of peanuts of which canopy development was relatively slow. Weed dry weight at harvest was negatively correlated with the number of pods and grain yield of peanuts. Among the yield components only the number of nods per plant was positively correlated with grain yield. Hana weeding after July 1 increased grain yield of Peanuts even in alchlor applied plots.

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The Effect of Common Features on Consumer Preference for a No-Choice Option: The Moderating Role of Regulatory Focus (재몰유선택적정황하공동특성대우고객희호적영향(在没有选择的情况下共同特性对于顾客喜好的影响): 조절초점적조절작용(调节焦点的调节作用))

  • Park, Jong-Chul;Kim, Kyung-Jin
    • Journal of Global Scholars of Marketing Science
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    • v.20 no.1
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    • pp.89-97
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    • 2010
  • This study researches the effects of common features on a no-choice option with respect to regulatory focus theory. The primary interest is in three factors and their interrelationship: common features, no-choice option, and regulatory focus. Prior studies have compiled vast body of research in these areas. First, the "common features effect" has been observed bymany noted marketing researchers. Tversky (1972) proposed the seminal theory, the EBA model: elimination by aspect. According to this theory, consumers are prone to focus only on unique features during comparison processing, thereby dismissing any common features as redundant information. Recently, however, more provocative ideas have attacked the EBA model by asserting that common features really do affect consumer judgment. Chernev (1997) first reported that adding common features mitigates the choice gap because of the increasing perception of similarity among alternatives. Later, however, Chernev (2001) published a critically developed study against his prior perspective with the proposition that common features may be a cognitive load to consumers, and thus consumers are possible that they are prone to prefer the heuristic processing to the systematic processing. This tends to bring one question to the forefront: Do "common features" affect consumer choice? If so, what are the concrete effects? This study tries to answer the question with respect to the "no-choice" option and regulatory focus. Second, some researchers hold that the no-choice option is another best alternative of consumers, who are likely to avoid having to choose in the context of knotty trade-off settings or mental conflicts. Hope for the future also may increase the no-choice option in the context of optimism or the expectancy of a more satisfactory alternative appearing later. Other issues reported in this domain are time pressure, consumer confidence, and alternative numbers (Dhar and Nowlis 1999; Lin and Wu 2005; Zakay and Tsal 1993). This study casts the no-choice option in yet another perspective: the interactive effects between common features and regulatory focus. Third, "regulatory focus theory" is a very popular theme in recent marketing research. It suggests that consumers have two focal goals facing each other: promotion vs. prevention. A promotion focus deals with the concepts of hope, inspiration, achievement, or gain, whereas prevention focus involves duty, responsibility, safety, or loss-aversion. Thus, while consumers with a promotion focus tend to take risks for gain, the same does not hold true for a prevention focus. Regulatory focus theory predicts consumers' emotions, creativity, attitudes, memory, performance, and judgment, as documented in a vast field of marketing and psychology articles. The perspective of the current study in exploring consumer choice and common features is a somewhat creative viewpoint in the area of regulatory focus. These reviews inspire this study of the interaction possibility between regulatory focus and common features with a no-choice option. Specifically, adding common features rather than omitting them may increase the no-choice option ratio in the choice setting only to prevention-focused consumers, but vice versa to promotion-focused consumers. The reasoning is that when prevention-focused consumers come in contact with common features, they may perceive higher similarity among the alternatives. This conflict among similar options would increase the no-choice ratio. Promotion-focused consumers, however, are possible that they perceive common features as a cue of confirmation bias. And thus their confirmation processing would make their prior preference more robust, then the no-choice ratio may shrink. This logic is verified in two experiments. The first is a $2{\times}2$ between-subject design (whether common features or not X regulatory focus) using a digital cameras as the relevant stimulus-a product very familiar to young subjects. Specifically, the regulatory focus variable is median split through a measure of eleven items. Common features included zoom, weight, memory, and battery, whereas the other two attributes (pixel and price) were unique features. Results supported our hypothesis that adding common features enhanced the no-choice ratio only to prevention-focus consumers, not to those with a promotion focus. These results confirm our hypothesis - the interactive effects between a regulatory focus and the common features. Prior research had suggested that including common features had a effect on consumer choice, but this study shows that common features affect choice by consumer segmentation. The second experiment was used to replicate the results of the first experiment. This experimental study is equal to the prior except only two - priming manipulation and another stimulus. For the promotion focus condition, subjects had to write an essay using words such as profit, inspiration, pleasure, achievement, development, hedonic, change, pursuit, etc. For prevention, however, they had to use the words persistence, safety, protection, aversion, loss, responsibility, stability etc. The room for rent had common features (sunshine, facility, ventilation) and unique features (distance time and building state). These attributes implied various levels and valence for replication of the prior experiment. Our hypothesis was supported repeatedly in the results, and the interaction effects were significant between regulatory focus and common features. Thus, these studies showed the dual effects of common features on consumer choice for a no-choice option. Adding common features may enhance or mitigate no-choice, contradictory as it may sound. Under a prevention focus, adding common features is likely to enhance the no-choice ratio because of increasing mental conflict; under the promotion focus, it is prone to shrink the ratio perhaps because of a "confirmation bias." The research has practical and theoretical implications for marketers, who may need to consider common features carefully in a practical display context according to consumer segmentation (i.e., promotion vs. prevention focus.) Theoretically, the results suggest some meaningful moderator variable between common features and no-choice in that the effect on no-choice option is partly dependent on a regulatory focus. This variable corresponds not only to a chronic perspective but also a situational perspective in our hypothesis domain. Finally, in light of some shortcomings in the research, such as overlooked attribute importance, low ratio of no-choice, or the external validity issue, we hope it influences future studies to explore the little-known world of the "no-choice option."

Multicenter Analysis of Gestational Trophoblastic Neoplasia in Turkey

  • Ozalp, Sabit Sinan;Telli, Elcin;Oge, Tufan;Tulunay, Gokhan;Boran, Nurettin;Turan, Taner;Yenen, Mufit;Kurdoglu, Zehra;Ozler, Ali;Yuce, Kunter;Ulker, Volkan;Arvas, Macit;Demirkiran, Fuat;Bese, Tugan;Tokgozoglu, Nedim;Onan, Anil;Sanci, Muzaffer;Gokcu, Mehmet;Tosun, Gokhan;Dikmen, Yilmaz;Ozsaran, Aydin;Terek, Mustafa Cosan;Akman, Levent;Yetimalar, Hakan;Kilic, Derya Sakarya;Gungor, Tayfun;Ozgu, Emre;Yildiz, Yunus;Kokcu, Arif;Kefeli, Mehmet;Kuruoglu, Serkan;Yuksel, Hasan;Guvenal, Tevfik;Hasdemir, Pinar Solmaz;Ozcelik, Bulent;Serin, Serdar;Dolanbay, Mehmet;Arioz, Dagistan Tolga;Tuncer, Nadire;Bozkaya, Hasan;Guven, Suleyman;Kulaksiz, Deniz;Varol, Fusun;Ali, Yanik;Ogurlu, Gonca;Simsek, Tayyup;Toptas, Tayfun;Dogan, Selen;Camuzoglu, Hakan;Api, Murat;Guzin, Kadir;Eray, Caliskan;Doger, Emek
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.8
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    • pp.3625-3628
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    • 2014
  • Background: To evaluate the incidence, diagnosis and management of GTN among 28 centers in Turkey. Materials and Methods: A retrospective study was designed to include GTN patients attending 28 centers in the 10-year period between January 2003 and May 2013. Demographical characteristics of the patients, histopathological diagnosis, the International Federation of Gynecology and Obstetrics (FIGO) anatomical and prognostic scores, use of single-agent and multi-agent chemotherapy, surgical interventions and prognosis were evaluated. Results: From 2003-2013, there were 1,173,235 deliveries and 456 GTN cases at the 28 centers. The incidence was calculated to be 0.38 per 1,000 deliveries. According to the evaluated data of 364 patients, the median age at diagnosis was 31 years (range, 15-59 years). A histopathological diagnosis was present for 45.1% of the patients, and invasive mole, choriocarcinoma and PSTTs were diagnosed in 22.3% (n=81), 18.1% (n=66) and 4.7% (n=17) of the patients, respectively. Regarding final prognosis, 352 (96.7%) of the patients had remission, and 7 (1.9%) had persistence, whereas the disease was mortal for 5 (1.4%) of the patients. Conclusions: Because of the differences between countries, it is important to provide national registration systems and special clinics for the accurate diagnosis and treatment of GTN.