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71.
Angiotensin converting enzyme (ACE) inhibitors are important for the treatment of hypertension as they can decrease the formation of vasopressor hormone angiotensin II (Ang II) and elevate the levels of vasodilating hormone bradykinin. It is observed that bradykinin contains a Ser-Pro-Phe motif near the site of hydrolysis. The selenium analogues of captopril represent a novel class of ACE inhibitors as they also exhibit significant antioxidant activity. In this study, several di- and tripeptides containing selenocysteine and cysteine residues at the N-terminal were synthesized. Hydrolysis of angiotensin I (Ang I) to Ang II by ACE was studied in the presence of these peptides. It is observed that the introduction of L-Phe to Sec-Pro and Cys-Pro peptides significantly increases the ACE inhibitory activity. On the other hand, the introduction of L-Val or L-Ala decreases the inhibitory potency of the parent compounds. The presence of an L-Pro moiety in captopril analogues appears to be important for ACE inhibition as the replacement of L-Pro by L-piperidine 2-carboxylic acid decreases the ACE inhibition. The synthetic peptides were also tested for their ability to scavenge peroxynitrite (PN) and to exhibit glutathione peroxidase (GPx)-like activity. All the selenium-containing peptides exhibited good PN-scavenging and GPx activities. 相似文献
72.
Starič M Aihara H Arinstein K Asner DM Aushev T Bakich AM Bay A Bhardwaj V Bhuyan B Bozek A Bračko M Browder TE Chen A Chen P Cheon BG Chilikin K Chistov R Cho IS Cho K Choi Y Doležal Z Drásal Z Eidelman S Fast JE Gaur V Gabyshev N Golob B Haba J Hayasaka K Horii Y Hoshi Y Hou WS Hsiung YB Iijima T Inami K Ishikawa A Itoh R Iwabuchi M Iwasaki Y Iwashita T Julius T Kang JH Kawasaki T Kiesling C Kim HJ Kim HO Kim JB Kim KT Kim MJ Kim YJ Kinoshita K Ko BR Kobayashi N Koblitz S Kodyš P Korpar S 《Physical review letters》2012,108(7):071801
We search for CP violation in Cabibbo-suppressed charged D meson decays by measuring the difference between the CP-violating asymmetries for the Cabibbo-suppressed decays D(±)→K(+)K(-)π(±) and the Cabibbo-favored decays D(s)(±)→K(+)K(-)π(±) in the K(+)K(-) mass region of the ? resonance. Using 955 fb(-1) of data collected with the Belle detector, we obtain A(CP)(D+→?π+)=(+0.51±0.28±0.05)%. The measurement improves the sensitivity of previous searches by more than a factor of 5. We find no evidence for direct CP violation. 相似文献
73.
Sato Y Yamamoto H Aihara H Asner DM Aulchenko V Aushev T Aziz T Bakich AM Bhardwaj V Bhuyan B Bischofberger M Bondar A Bozek A Bračko M Browder TE Chang P Chen P Cheon BG Chilikin K Chistov R Cho IS Cho K Choi SK Choi Y Dalseno J Doležal Z Drásal Z Eidelman S Epifanov D Fast JE Gaur V Gabyshev N Goh YM Golob B Haba J Hara T Hayasaka K Hayashii H Horii Y Hoshi Y Hou WS Hyun HJ Ishikawa A Itoh R Iwabuchi M Iwasaki Y Iwashita T Julius T Kapusta P Kawasaki T Kichimi H Kiesling C Kim HJ Kim HO 《Physical review letters》2012,108(17):171801
We report a measurement of the CP-violation parameter sin2φ1 at the Υ(5S) resonance using a new tagging method, called "B-π tagging." In Υ(5S) decays containing a neutral B meson, a charged B, and a charged pion, the neutral B is reconstructed in the J/ψK(S)(0) CP-eigenstate decay channel. The initial flavor of the neutral B meson at the moment of the Υ(5S) decay is opposite to that of the charged B and may thus be inferred from the charge of the pion without reconstructing the charged B. From the asymmetry between B-π(+) and B-π(-) tagged J/ψK(S)(0) yields, we determine sin2φ1=0.57±0.58(stat)±0.06(syst). The results are based on 121 fb(-1) of data recorded by the Belle detector at the KEKB e(+)e(-) collider. 相似文献
74.
75.
R. Stoian J. P. Colombier C. Mauclair G Cheng M. K. Bhuyan P. K. Velpula P. Srisungsitthisunti 《Applied Physics A: Materials Science & Processing》2014,114(1):119-127
The spatio-temporal design of ultrafast laser excitation can have a determinant influence on the physical and engineering aspects of laser–matter interactions, with the potential of upgrading laser processing effects. Energy relaxation channels can be synergetically stimulated as the energy delivery rate is synchronized with the material response on ps timescales. Experimental and theoretical loops based on the temporal design of laser irradiation and rapid monitoring of irradiation effects are, therefore, able to predict and determine ideal optimal laser pulse forms for specific ablation objectives. We illustrate this with examples on manipulating the thermodynamic relaxation pathways impacting the ablation products and nanostructuring of bulk and surfaces using longer pulse envelopes. Some of the potential control factors will be pointed out. At the same time the spatial character can dramatically influence the development of laser interaction. We discuss spatial beam engineering examples such as parallel and non-diffractive approaches designed for high-throughput, high-accuracy processing events. 相似文献
76.
Ko BR Won E Arinstein K Aushev T Bakich AM Balagura V Barberio E Belous K Bhardwaj V Bhuyan B Bischofberger M Bondar A Bozek A Bračko M Brodzicka J Browder TE Chen A Chen P Cheon BG Chiang CC Cho IS Cho K Choi KS Choi SK Choi Y Eidelman S Epifanov D Feindt M Gabyshev N Garmash A Golob B Ha H Haba J Hayashii H Horii Y Hoshi Y Hou WS Hyun HJ Iijima T Inami K Ishikawa A Itoh R Iwabuchi M Iwashita T Julius T Kang JH Kawasaki T Kiesling C Kim HO Kim MJ Kim YJ Kinoshita K Kodyš P Korpar S Križan P 《Physical review letters》2011,106(21):211801
We have searched for CP violation in the decays D(0)→K(S)(0)P(0) where P(0) denotes a neutral pseudoscalar meson that is either a π(0), η, or η' using KEKB asymmetric-energy e(+)e(-) collision data corresponding to an integrated luminosity of 791 fb(-1) collected with the Belle detector. No evidence of significant CP violation is observed. We report the most precise CP asymmetry measurement in the decay D(0)→K(S)(0)π(0) to date: A(CP)(D(0)→K(S)(0)π(0))=(-0.28±0.19±0.10)%. We also report the first measurements of CP asymmetries in the decays D(0)→K(S)(0)η and D(0)→K(S)(0)η': A(CP)(D(0)→K(S)(0)η)=(+0.54±0.51±0.16)% and A(CP)(D(0)→K(S)(0)η')=(+0.98±0.67±0.14)%, respectively. 相似文献
77.
Pallabi Borah P. Seetham Naidu Swarup Majumder Pulak J. Bhuyan 《Molecular diversity》2014,18(4):759-767
One-pot multi-component reaction of 3-cyanoacetyl indole, aromatic aldehydes and ethyl acetoacetate in the presence of \(\hbox {InCl}_{3}/\hbox {NH}_{4}\) OAc under microwave irradiation for 2–7 min afforded novel and highly functionalized 3-(pyranyl)- and 3-(dihydropyridinyl)indole derivatives, respectively, in good yield. 相似文献
78.
Bipul Bhuyan 《Pramana》2004,62(3):573-578
The experimental progress in the search forK
+
→ π
+
v-v will be presented in this paper. Also the physics potential of the proposed BNL experiment to search forK
L
O
→ πo
v-v (KOPIO) will be discussed. 相似文献
79.
Some novel spiro substituted pyrido[2,3-c]coumarin derivatives were synthesized from 4-hydroxycoumarin by exploring ‘tertiary amino effect’ reaction strategy. 相似文献
80.
Three sharp absorption features in the energy range 2.36–2.55 eV have been detected in the transmission spectrum of Co-diffused ZnSe, and a number of luminescence transitions originating from the lowest of these states at 2.361 eV have been observed. Photoluminescence excitation spectra prove that these are high energy excited states of the Co2+Zn impurity, a conclusion confirmed by comparison of measured and predicted luminescence energies. This represents the first identification of luminescence branching from a higher excited state of a transition metal ion in any semiconductor. The sharp, weakly phonon-coupled transitions involve either intra-impurity excitation or transitions from the impurity to localised states split off from a minimum in the conduction band. The implications of these observations for the mechanism of host-impurity energy transfer and for the nature of the excited state wavefunctions are discussed. 相似文献