Effect of modification of the electrophilic center on the α effect

2005 ◽  
Vol 83 (9) ◽  
pp. 1365-1371 ◽  
Author(s):  
Ik-Hwan Um ◽  
Ji-Youn Lee ◽  
Sun-Young Bae ◽  
Erwin Buncel
Keyword(s):  
Ground State ◽  
Strong Dependence ◽  
Solvation Energy ◽  
The Other ◽  
Substrate Structure ◽  
Leaving Group ◽  
The Common ◽  
The Difference ◽  
The Impact

We report on a nucleophilic study of esters R-C(=X)-Y-Ar in which the electrophilic center has been modified by replacing O by S in the leaving group or carbonyl center: 4-nitrophenyl acetate (1), S-4-nitrophenyl thioacetate (2), 4-nitrophenyl benzoate (3), and O-4-nitrophenyl thionobenzoate (4). The studies include O– and S– nucleophiles as well as α nucleophiles in H2O at 25.0 ± 0.1 °C. The sulfur nucleophile (4-chlorothiophenoxide, 4-ClPhS–) exhibits significant enhanced reactivity for the reactions with thiol and thione esters 2 and 4 compared with their oxygen analogues 1 and 3. On the contrary, the common nucleophile OH– is much less reactive towards 2 and 4 compared with 1 and 3. The effect of changing both the electrophilic center and the nucleofugic center on the reactivity of the other oxygen nucleophiles is not so significant: 4-chlorophenoxide (4-ClPhO–) is four to six times more reactive in the reactions with thiol and thione esters 2 and 4 compared with their oxygen analogues 1 and 3. The α effects exhibited by butan-2,3-dione monoximate (Ox–) and HOO– are strongly dependent on the nature of the electrophilic center of the substrates, indicating that the difference in the ground-state solvation energy cannot be fully responsible for the α effect. Our results clearly emphasize the strong dependence of the α effect on the substrate structure, notably, the nature of the electrophilic center. The impact of change in the nucleofuge (1→2) and the electrophilic center (3→4) on reactivity indicates that α nucleophiles will need to be “purpose built” for decontamination and nucleophilic degradation of specific biocides.Key words: α effect, nucleophilicity, nucleofuge effect, electrophilicity, polarizability.

scholarly journals Investigating the properties of a galaxy group at z = 0.6

2020 ◽  
Vol 15 (S359) ◽  
pp. 188-189
Author(s):  
Daniela Hiromi Okido ◽  
Cristina Furlanetto ◽  
Marina Trevisan ◽  
Mônica Tergolina
Keyword(s):  
Large Scale ◽  
The Other ◽  
Numerical Density ◽  
Spectroscopy Data ◽  
Stellar Kinematics ◽  
Galaxy Groups ◽  
The Galaxy ◽  
The Difference ◽  
The Impact ◽  
The Universe

AbstractGalaxy groups offer an important perspective on how the large-scale structure of the Universe has formed and evolved, being great laboratories to study the impact of the environment on the evolution of galaxies. We aim to investigate the properties of a galaxy group that is gravitationally lensing HELMS18, a submillimeter galaxy at z = 2.39. We obtained multi-object spectroscopy data using Gemini-GMOS to investigate the stellar kinematics of the central galaxies, determine its members and obtain the mass, radius and the numerical density profile of this group. Our final goal is to build a complete description of this galaxy group. In this work we present an analysis of its two central galaxies: one is an active galaxy with z = 0.59852 ± 0.00007, while the other is a passive galaxy with z = 0.6027 ± 0.0002. Furthermore, the difference between the redshifts obtained using emission and absorption lines indicates an outflow of gas with velocity v = 278.0 ± 34.3 km/s relative to the galaxy.

128 Differences in PRRSV Resilience for Reproductive Performance Between Landrace and Duroc Sows

2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 18-19
Author(s):  
Felipe Hickmann ◽  
José Braccini Neto ◽  
Luke M Kramer ◽  
Kent A Gray ◽  
Yijian Huang ◽  
...  
Keyword(s):  
Reproductive Performance ◽  
Mixed Model ◽  
Performance Data ◽  
The Other ◽  
Wild Type ◽  
Prrs Virus ◽  
The Difference ◽  
The Impact

Abstract Studies on differences in resilience to porcine reproductive and respiratory syndrome (PRRS) virus (PRRSV) between breeds are scarce in the literature. Thus, the objective of this work was to assess PRRSV resilience in PRRSV wild-type infected sows from two breeds. Farrowing data included 2546 and 2522 litters from 894 Duroc and 813 Landrace sows, respectively, which were housed together and experienced the same PRRSV outbreak. Traits used for this study were number of piglets born alive (NBA), number born dead (NBD), total number born (TNB), and number weaned (NW). The impact of PRRSV infection was evaluated by comparing the reproductive performance of breeds between PRRS phases (pre-PRRS, PRRS, and post-PRRS). PRRS phases were defined based on the reproductive performance data. NBA, NBD, and NW were analyzed as a proportion of TNB using a Poisson mixed model. Pre-defined contrasts were used to evaluate the effect of breed on PRRSV resilience and on return to PRRSV-free performance, representing the differences between breeds for the difference between pre-PRRS and PRRS phases, and pre-PRRS and post-PRRS phases, respectively. There was a significant (P ≤ 0.003) interaction between PRRS phase and breed for all traits, as shown in Table 1. In general, reproductive performance reduced from pre-PRRS to PRRS, and then increased from PRRS to post-PRRS, as expected. The resilience contrast was significant for all traits (P ≤ 0.003). In all cases, the drop in percent reproductive performance from pre-PRRS to PRRS was lower for Duroc than for Landrace, indicating that Duroc sows have greater PRRSV resilience than Landrace sows. The return to PRRSV-free performance contrast had a trending effect for NBD (P = 0.055), and it was not significant for the other traits (P ≥ 0.515). These results indicate that Duroc sows have overall greater phenotypic PRRSV resilience for reproductive performance than Landrace sows.

scholarly journals The Impact of Human Capital on Stocks Performance in Emerging Markets: Evidence From Egypt

2020 ◽  
Vol 10 (1) ◽  
pp. 73
Author(s):  
Walid Abouzeid ◽  
Sharihan Mohamed Aly
Keyword(s):  
Human Capital ◽  
Emerging Markets ◽  
Banking Sector ◽  
The Other ◽  
Common Stock ◽  
General Tendency ◽  
Other Hand ◽  
The Common ◽  
The Impact ◽  
Statistical Results

This study attempts to investigate the impact of human capital on the common stock's return. The population of the study is Egyptian companies listed at the Egyptian exchange (EGX) due to 2014-2018. The statistical results indicate that there is a general tendency to change common stock's hold return to the corporation's human capital, and it is significant at 0.01 levels. In other terms, it can be stated that the corporation's human capital has a significant impact on common stock's hold return in the Egyptian corporation, and according to Adjusted R-squared the corporation's human capital explain a 57.8% from the change common stock's hold return.so; led to the impact of human capital on creating value of common stock. This can be traced back to investing in "the development and researches" on the other hand besides training, therefore medicine and technology companies get affected through these fields of development researches areas; however companies in industrial and banking sector get impacted by training field.

Entrepreneurship vs. Bioentrepreneurship

2021 ◽  
pp. 39-58
Author(s):  
Sneha Upreti
Keyword(s):  
The Other ◽  
Future Perspective ◽  
Developed Country ◽  
Other Hand ◽  
Start Up ◽  
Great Idea ◽  
New Business ◽  
Innovative Idea ◽  
The Common ◽  
The Difference

The word bioentrepreneurship and entrepreneurship share the similarity in the fact that they must have a great and an innovative idea behind starting a business setup and to raise an investment. Also, they both must have a great idea about marketing of the related products and managing their start-up. If we talk about the difference, the common difference is the sector or field in which a startup is carrying on. In simple words, entrepreneurship is the process of launching any new business based on an innovative idea. On the other hand, bioentrepreneurship is the process that is started in the field of science (i.e., biotechnology). Nowadays, bio-industrialization is the key to being a modern and developed country, and this is the only reason bioentrepreneurs are highly in demand. Thus, this chapter will help you to understand the pillars to setup a startup based on biotechnology that has an excellent future perspective not only for entrepreneurs but also for the nation.

Imperatives of visual versus auditory perception as pragmatic markers in English and Dutch

2010 ◽  
Vol 3 (1) ◽  
pp. 74-94 ◽  
Author(s):  
Daniël Van Olmen
Keyword(s):  
Frequency Distribution ◽  
Auditory Perception ◽  
The Other ◽  
Common View ◽  
Pragmatic Markers ◽  
The Common ◽  
The Difference ◽  
The One

This article examines the English and Dutch imperatives of intentional visual and auditory perception and in particular their use as pragmatic markers. Look, listen, kijk ‘look’ and luister ‘listen’ are compared with respect to frequency, distribution and usage. The difference between look and kijk, on the one hand, and listen and luister, on the other, is argued to be indicative of a more general cross-linguistic tendency. This tendency is explained in terms of the imperatives’ effectiveness in and likely recruitment for what has traditionally been called attention-getting and in terms of the common view of the nature of visual and auditory perception.

scholarly journals Participating is more important than winning: the impact of socio-economic change on commoners' participation in eighteenth- and nineteenth-century Flanders

2010 ◽  
Vol 25 (3) ◽  
pp. 405-433 ◽  
Author(s):  
TINE DE MOOR
Keyword(s):  
Nineteenth Century ◽  
Resource Use ◽  
The Other ◽  
Willingness To Participate ◽  
Registration System ◽  
Regulatory Documents ◽  
The Common ◽  
The One ◽  
The Impact

ABSTRACTIn this article the participation profile of commoners of a Flemish case-study is reconstructed in order to identify their individual motivations for using the common, in some cases even becoming a manager of that common, in some cases only just claiming membership. Nominative linkages between membership lists, book-keeping accounts and regulatory documents of the common on the one hand and censuses and marriage acts on the other allow us to explain the behaviour of the commoners. It becomes clear why some decisions were taken – for example, to dissolve a well-functioning cattle-registration system – and how these affected the resource use of the common during the eighteenth and early nineteenth centuries. The analysis explains how internal shifts in power balances amongst groups of active users and those who did not have the means or willingness to participate could jeopardize the internal cohesion of the commoners as a group.

scholarly journals The difference of jurists in the development of the Quran Alkarim

2018 ◽  
Vol 227 (2) ◽  
pp. 135-153
Author(s):  
Dr. Naseer kareem Kazem Al Saadi
Keyword(s):  
The Other ◽  
Common People ◽  
The Common ◽  
The Difference

The study of the reasons for the difference of jurists in the development is an attempt to alleviate the tension caused by the difference between them, as well as being the presentation of the culture of opinion and opinion of the other, not every difference between scientists leads to the boycott and quarrel among the common people, is a sincere invitation to show that we disagree with The dispute, we want to clarify that there are natural reasons are called for the difference, such as issues follow the character of the jurist, through the nature of the language that the Koran came down, which led to differences of scholars in the extraction of the Koran

Communism in the Islamic World

2013 ◽  
Author(s):  
Anne Alexander
Keyword(s):  
Global Economy ◽  
The Other ◽  
National Liberation ◽  
Capitalist Development ◽  
Islamic World ◽  
Post Colonial ◽  
History Of ◽  
Muslim Majority ◽  
The Common ◽  
The Impact

This essay explores some of the common patterns in the history of communism in Muslim-majority societies. The most important of these had little to with Islam. Rather, they reflected the impact of European imperialism and nationalist resistance, the uneven tempo of integration into the global economy, the timing of the anti-colonial revolutions and the location of the post-colonial regimes in the great games of geopolitics. However, the other side of this narrative is the interwoven story of the decline of communist movements in most Muslim-majority societies and the rise of their Islamist competitors. It is argued that this trajectory is best explained not by recourse to essentialist explanations about the appeal of Islamist politics to Muslim believers, but by the failures of the post-colonial states on which the communists had pinned their hopes for national liberation and non-capitalist development.

Effect of co-contaminants on the dechlorination of polychlorinated biphenylsPaper submitted to the Journal of Environmental Engineering and Science.

2010 ◽  
Vol 37 (4) ◽  
pp. 667-674
Author(s):  
Macoura Kone ◽  
Yanjun Chang ◽  
Gopal Achari ◽  
Cooper H. Langford
Keyword(s):  
Uv Irradiation ◽  
Reaction Medium ◽  
Transformer Oil ◽  
Pcb Congeners ◽  
Weathered Soils ◽  
The Common ◽  
The Difference ◽  
The Individual ◽  
The Impact ◽  
Complete Dechlorination

A promising photolysis based technology to dechlorinate polychlorinated biphenyls (PCBs), extracted from soils, in alkaline isopropanol (IPA) as reaction medium has been proposed. To be marketable the impact of co-contaminants extracted along with the PCBs, on the photodechlorination process needs investigation. In this paper the effectiveness of the photodeclorination process on PCBs extracted from samples of a representative soil containing co-contaminants is reported. The photodechlorination of PCBs extracted from weathered soils showed promising results of more than 76% dechlorination within the first hour of UV irradiation. Nearly complete dechlorination (96%) was achieved after 2 h of UV irradiation. To provide quantitative controlled appraisal of the effect of co-contaminants and explanation of the effects, dechlorination of neat Aroclor 1254 in the presence of the common co-contaminant, transformer oil, was evaluated. Further, the effect of transformer oil on some of the individual PCB congeners in the Aroclor mixture was also studied. The difference in the maximum percentage dechlorination of PCBs with and without transformer oil is 15%.

scholarly journals The CCR5-delta32 variant might explain part of the association between COVID-19 and the chemokine-receptor gene cluster

2020 ◽  
Author(s):  
Juan Gómez ◽  
Elías Cuesta-Llavona ◽  
Guillermo M. Albaiceta ◽  
Marta García-Clemente ◽  
Carlos López-Larrea ◽  
...  
Keyword(s):  
Gene Cluster ◽  
Chemokine Receptor ◽  
Receptor Gene ◽  
Chromosome 3P ◽  
Reduced Frequency ◽  
Promising Target ◽  
The Common ◽  
The Difference ◽  
The Impact ◽  
Chemokine Receptor Gene

AbstractA polymorphism in the LZTFL1 gene located in the chemokine-receptor gene cluster (chromosome 3p) has been associated with the risk of developing COVID-19. The chemokine receptor-5 (CCR5) maps to this region, and the common 32 bp deletion variant (Δ32) has been associated with the extent of inflammatory disease and the outcome in several viral diseases. Several studies have also suggested that the pharmacological targeting of CCR5 could reduce the impact of SARS-CoV-2 infection and the severity of COVID-19. We sought to investigate whether this polymorphism was associated with the risk of moderate-severe COVID-19.We genotyped 294 patients who required hospitalization due to COVID-19 (85 were severe cases) and 460 controls. We found a significantly lower frequency of CCR5-Δ32 among the COVID-19 patients (0.10 vs 0.18 in controls; p=0.002, OR=0.48, 95%CI=0.29-0.76). The difference was mainly due to the reduced frequency of CCR5-Δ32 carriers in the severe, significantly lower than in the non-severe patients (p=0.036). Of note, we did not find deletion-homozygotes among the patients compared to 1% among controls. We also confirmed the association between a LZTFL1 variant and COVID-19. Our study points to CCR5 as a promising target for treatment of COVID-19, but requires validation in additional large cohorts. In confirmed by others, the genetic analysis of CCR5-variants (such as Δ32) might help to identify patients with a higher susceptibility to severe COVID-19.

Sign in / Sign up

Export Citation Format

Share Document