Rearrangement studies with 14C. XLIII. The acetolysis of trianisyl[2-14C]vinyl bromide

1979 ◽  
Vol 57 (11) ◽  
pp. 1384-1387 ◽  
Author(s):  
Choi Chuck Lee ◽  
Ursula Weber ◽  
Craig A. Obafemi

Acetolyses of trianisyl[2-14C]vinyl bromide (1-Br-2-14C) were carried out in the presence of various amounts of added NaOAc or NaOAc and LiBr. Scramblings of the isotopic label from C-2 to C-1 arising from 1,2-anisyl shifts in the trianisylvinyl cation were observed in both the reaction product and the recovered, unconsumed reactant. The results indicate that the relative contribution of the 1,2-shift process is decreased with an increase in the amount of NaOAc or LiBr, in support of a mechanism involving formation of the dissociated trianisylvinyl cation which will competitively undergo 1,2-anisyl shift to give scrambling, be captured by Br− ion and return to scrambled starting material, and be captured by OAc− ion to give scrambled product. The results are also compared with previous data from solvolyses of triphenyl[2-14C]vinyl bromide and the differences are discussed.

2003 ◽  
Vol 8 (4) ◽  
pp. 252-265 ◽  
Author(s):  
Manuel G. Calvo ◽  
P. Avero ◽  
M. Dolores Castillo ◽  
Juan J. Miguel-Tobal

We examined the relative contribution of specific components of multidimensional anxiety to cognitive biases in the processing of threat-related information in three experiments. Attentional bias was assessed by the emotional Stroop word color-naming task, interpretative bias by an on-line inference processing task, and explicit memory bias by sensitivity (d') and response criterion (β) from word-recognition scores. Multiple regression analyses revealed, first, that phobic anxiety and evaluative anxiety predicted selective attention to physical- and ego-threat information, respectively; cognitive anxiety predicted selective attention to both types of threat. Second, phobic anxiety predicted inhibition of inferences related to physically threatening outcomes of ambiguous situations. And, third, evaluative anxiety predicted a response bias, rather than a genuine memory bias, in the reporting of presented and nonpresented ego-threat information. Other anxiety components, such as motor and physiological anxiety, or interpersonal and daily-routines anxiety made no specific contribution to any cognitive bias. Multidimensional anxiety measures are useful for detecting content-specificity effects in cognitive biases.


Diabetes ◽  
1993 ◽  
Vol 42 (5) ◽  
pp. 720-731 ◽  
Author(s):  
G. M. Steil ◽  
M. A. Meador ◽  
R. N. Bergman

2019 ◽  
Author(s):  
Krisztina Sára Lukics ◽  
Ágnes Lukács

First language acquisition is facilitated by several characteristics of infant-directed speech, but we know little about their relative contribution to learning different aspects of language. We investigated infant-directed speech effects on the acquisition of a linear artificial grammar in two experiments. We examined the effect of incremental presentation of strings (starting small) and prosody (comparing monotonous, arbitrary and phrase prosody). Presenting shorter strings before longer ones led to higher learning rates compared to random presentation. Prosody marking phrases had a similar effect, yet, prosody without marking syntactic units did not facilitate learning. These studies were the first to test the starting small effect with a linear artificial grammar, and also the first to investigate the combined effect of starting small and prosody. Our results suggest that starting small and prosody facilitate the extraction of regularities from artificial linguistic stimuli, indicating they may play an important role in natural language acquisition.


Author(s):  
Z.B. Baktybaeva ◽  
R.A. Suleymanov ◽  
T.K. Valeev ◽  
N.R. Rakhmatullin

Carried out ecological and hygienic assessment of pollution of surface and groundwater of mining areas in the Republic of Bashkortostan. Revealed exceeding standards for fishery water bodies and drinking and cultural and community water use, which indicates the potential danger of surface water for the health of the region's population. The greatest relative contribution to the overall pollution of surface water bodies are making manganese (33,0–66,6 %), iron (9,1–15,6 %), calcium (6,5–11,7 %), lead (5,8– 7,2 %). The quality of water used for drinking purposes from decentralized water sources (boreholes, wells, springs), do not always correspond to the hygienic and sanitary-epidemiological requirements. In this case, the highest priority performance of drinking water contamination are increased stiffness, high content of iron, calcium, nitrate, presence cadmium, and hexavalent chromium.


Author(s):  
I.A. Petukhova ◽  
V.K. Riabchun ◽  
V.A. Muzapharova ◽  
O.I. Padalka ◽  
T.A. Sheliakina ◽  
...  

The goal of our research was to form a collection of groats barley, to search, to select and to evaluate starting material of spring barley for a set of valuable economic traits, technological properties and culinary qualities of barley groats. Results and Discussion. Basing on to the results of assessments, we identified selected 55 spring barley accessions, which were characterized by 17 traits and 75 expression levels. The collection includes accessions from 11 countries; the largest number of accessions (59) are from Ukraine; 39 – from Russia; 10 - from Belarus; 10 - from Germany; 6 - from France; 5 - from Kazakhstan; 4 - from Canada; 3 - from the Czech Republic; 2 – from Great Britain; 1 accesson is from Serbia; and 1 - from Austria. Accessions combining high levels of expression of different traits are the most valuable. They include the following accessions: Doridnyi, Vodohrai, Sviatomykhailivskyi, Svarozhych, Soka, Іlot (UKR). Naked accessions include: Akhilles (UKR), Mayskiy, Oskar, Golozyornyy 1, Omskiy Golozyornyy 1 (RUS), CDC Alamo, CDC Candle (CAN). These varieties can be starting material for creation of new modern high-performance spring groats barley varieties. Ten valuable accessions registered with the NCPGRU (Sovіra, Doridnyi, Soka, Vodohrai, Partner, Yukatan, Avhii, Svarozhych, Baskak, and Virtuoz) were included in the trait groats collection. Conclusions. Basing on the results of multiyear studies, we formed the trait collection of spring groats barley comprising 140 accessions from 11 countries. The collection includes 55 reference accessions that cover 17 traits (plant height, vegetation period, ear length, grain weight per ear, 1000-grain weight, grain shape, grain evenness, vitreousness, culinary qualities of barley groats, etc.) characterized by 75 levels of their expression. The collection is of considerable value for science and education. The accessions selected allow improving the efficiency of breeding to create new varieties with high technological and culinary properties as well as with a set of valuable economic characteristics.


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