2,330 research outputs found
Фармакофорна модель для скринінгу протистафілококової активності серед тіазолідинон-споріднених структур
Aim. To develop a pharmacophore model suitable for the antistaphylococcal activity screening among thiazolidinone, thiopyrano[2,3-d]thiazole and thiazolo[4,5-b]pyridine derivatives.Results and discussion. The best pharmacophore model in the series of models developed has a planar structure and consists of an aromatic ring (or cycle with π-bonds), a hydrophobic region, a projection of a hydrogen bond donor and two projections of a hydrogen bond acceptor. Its classification accuracy is 72.4 %. The diameter line of the model is formed by the projection of the hydrogen bond donor and the projection of the hydrogen bond acceptor, and its length is 8.05 Å. The analysis of conformations of active compounds consistent with the pharmacophore mode revealed two different ways of spatial arrangement of active molecules, in which the conditions of the pharmacophore model are fully met.Experimental part. The antistaphylococcal activity was determined by the agar diffusion method against methicillin-resistant strain of Staphylococcus aureus (MRSA) and evaluated by measuring the diameter of the microbial growth inhibition zone. The plates were incubated for 24 h at 37 °C. Compounds with the growth inhibition diameter of more than 7.5 mm were considered to be active. Computer processing of the results of the microbiological experiment and modeling of the probable pharmacophore were performed in the MOE software environment version 2007.09. The geometry of the compounds was optimized by molecular mechanics using the MMFF94x force field. Accuracy of classification was used as the main quality criterion of the pharmacophore model.Conclusions. The pharmacophore model developed can be used for virtual screening of the antistaphylococcal activity for the compounds similar to the training sample. When applying it to the in-home database of compounds the enrichment factor is EF = 2.05.Received: 27.09.2020 Revised: 23.10.2020 Accepted: 03.11.2020Мета. Розробити фармакофорну модель, придатну для скринінгу протистафілококової активності серед похідних тіазолідинону, тіопірано[2,3-d]тіазолу, тіазоло[4,5-b]піридину.Результати та їх обговорення. Найкраща фармакофорна модель у серії розроблених має планарну структуру і складається з ароматичного кільця (або циклу з π-зв’язками), гідрофобної області, проєкції донора водневого зв’язку та двох проєкцій акцептора водневого зв’язку. Її точність класифікації становить 72,4 %. Лінія діаметра моделі утворена проєкцією донора та проєкцією акцептора водневого зв’язку, а її довжина дорівнює 8,05 Å. Під час аналізу узгоджених з фармакофорною моделлю конформацій активних сполук виявлено два різні способи просторового розміщення активних молекул, за яких повною мірою виконуються умови фармакофорної моделі.Експериментальна частина. Протистафілококову активність визначали методом дифузії в агар щодо резистентного до метициліну штаму Staphylococcus aureus (MRSA) й оцінювали шляхом вимірювання діаметра зони інгібування мікробного зростання. Планшети інкубували протягом 24 год за 37 °С. Сполуки з діаметром затримки розмноження мікроорганізмів понад 7,5 мм вважали активними. Комп’ютерне оброблення результатів мікробіологічного експерименту та моделювання ймовірного фармакофора виконували в програмному середовищі MOE версії 2007.09. Геометрію сполук оптимізували методом молекулярної механіки з використанням силового поля MMFF94x. Точність класифікації використовували як основний критерій оцінювання якості фармакофорної моделі.Висновки. Розроблену фармакофорну модель можна використовувати для віртуального скринінгу протистафілококової активності споріднених із навчальною вибіркою сполук. Під час застосування цієї моделі до бази даних протестованих нами сполук з’ясували, що фактор збагачення складає EF = 2,05.Received: 27.09.2020 Revised: 23.10.2020 Accepted: 03.11.202
Biopolymer-based structuring of liquid oil into soft solids and oleogels using water-continuous emulsions as templates
Physical trapping of a hydrophobic liquid oil in a matrix of water-soluble biopolymers was achieved using a facile two-step process by first formulating a surfactant-free oil-in-water emulsion stabilized by biopolymers (a protein and a polysaccharide) followed by complete removal of the water phase (by either high- or low-temperature drying of the emulsion) resulting in structured solid systems containing a high concentration of liquid oil (above 97 wt %). The microstructure of these systems was revealed by confocal and cryo-scanning electron microscopy, and the effect of biopolymer concentrations on the consistency of emulsions as well as the dried product was evaluated using a combination of small-amplitude oscillatory shear rheometry and large deformation fracture studies. The oleogel prepared by shearing the dried product showed a high gel strength as well as a certain degree of thixotropic recovery even at high temperatures. Moreover, the reversibility of the process was demonstrated by shearing the dried product in the presence of water to obtain reconstituted emulsions with rheological properties comparable to those of the fresh emulsion
Сучасний стан поширення фасціольозу великої рогатої худоби в Україні
In order to study the prevalence of bovine fasciolosis in different regions of Ukraine, we analysed the generalised annual statistical reports of the State Research Institute for Laboratory Diagnostics and Veterinary and Sanitary Expertise on the results of laboratory tests of biological material. The dynamics of infection was studied for the period 2020–2023. Based on the results of our own research, it was found that the highest rates of fasciolosis in livestock were recorded in the northwestern regions: in Rivne region, the prevalence was 4.42 ± 0.58 %, in Lviv region – 3.15 ± 0.14 %, in Chernihiv region – 2.19 ± 0.19 %, in Sumy region – 3.0 ± 0.112 %, in Ternopil region – 1.98 ± 0.13 %, in Zhytomyr and Volyn regions – 1.86 ± 0.08 % and 1.64 ± 0.12 %, respectively. It is worth noting that the overall indicators of the extent of the infestation in these regions did not fluctuate significantly during 2020 – 2023. The absence of significant fluctuations in the incidence of cattle with the fascioliasis pathogen indicates the existence of stationary foci of fasciolosis infection in these regions. At the same time, a decrease in the number of studies of biological material samples from cattle by 48.4 % compared to 2020 and 2023, which is likely due to a sharp reduction in livestock during the war, means that the level of animal infection with the fascioliasis pathogen has remained almost at the same level during the observation period. It has been found that the level of cattle infection depends on the type of animal housing and feeding. Cattle kept in livestock farms, taking into account the technology of using canned feed, are less affected by fascioliasis than cattle of the private sector that graze freely.Для визначення поширення фасціольозу великої рогатої худоби в різних регіонах України проводили аналіз річної статистичної звітності Державного науково-дослідного інституту з лабораторної діагностики та ветеринарно-санітарної експертизи щодо результатів лабораторних випробувань біологічного матеріалу. Динаміку інвазованості вивчали за період 2020–2023 років. За результатами власних досліджень встановлено, що найбільші показники ураження великої рогатої худоби фасціолами зареєстровано в північно-західних регіонах: у Рівненській області екстенсивність інвазії становила 4,42 ± 0,58 %, у Львівській області – 3,15 ± 0,14 %, у Чернігівській – 2,19 ± 0,19 %, у Сумській – 3,0 ± 0,11 %, у Тернопільській– 1,98 ± 0,13 %, у Житомирській та Волинській областях – 1,86 ± 0,08 % та 1,64 ± 0,12 % відповідно. Варто зазначити, що загальні показники екстенсивності інвазії у цих регіонах упродовж 2020–2023 років не зазнали значних коливань. Відсутність значної різниці у показниках ураженості великої рогатої худоби збудником фасціольозу свідчить про існування у цих областях стаціонарних вогнищ інвазії. Водночас виявляли зменшення досліджень кількості зразків біологічного матеріалу від великої рогатої худоби на 48,4 %, порівнюючи за 2020 та 2023 роки, що, ймовірно, пов’язано з різким скороченням поголів’я в умовах війни. Проте ураження тварин збудником фасціольозу перебувало майже на одному рівні упродовж всього періоду спостережень. Виявлено, що рівень ураженості великої рогатої худоби залежить від типу утримання та годівлі. Велика рогата худоба, що утримується в умовах тваринницьких ферм, враховуючи технологію використання консервованих кормів, менше уражається фасціолами, аніж худоба приватного сектору, що вільно випасається на різних пасовищах і луках
First Observation of CP Violation in B0->D(*)CP h0 Decays by a Combined Time-Dependent Analysis of BaBar and Belle Data
We report a measurement of the time-dependent CP asymmetry of B0->D(*)CP h0
decays, where the light neutral hadron h0 is a pi0, eta or omega meson, and the
neutral D meson is reconstructed in the CP eigenstates K+ K-, K0S pi0 or K0S
omega. The measurement is performed combining the final data samples collected
at the Y(4S) resonance by the BaBar and Belle experiments at the
asymmetric-energy B factories PEP-II at SLAC and KEKB at KEK, respectively. The
data samples contain ( 471 +/- 3 ) x 10^6 BB pairs recorded by the BaBar
detector and ( 772 +/- 11 ) x 10^6, BB pairs recorded by the Belle detector. We
measure the CP asymmetry parameters -eta_f S = +0.66 +/- 0.10 (stat.) +/- 0.06
(syst.) and C = -0.02 +/- 0.07 (stat.) +/- 0.03 (syst.). These results
correspond to the first observation of CP violation in B0->D(*)CP h0 decays.
The hypothesis of no mixing-induced CP violation is excluded in these decays at
the level of 5.4 standard deviations.Comment: 9 pages, 2 figures, submitted to Physical Review Letter
Measurement of CP Asymmetries and Branching Fractions in Charmless Two-Body B-Meson Decays to Pions and Kaons
We present improved measurements of CP-violation parameters in the decays
, , and , and of
the branching fractions for and . The
results are obtained with the full data set collected at the
resonance by the BABAR experiment at the PEP-II asymmetric-energy factory
at the SLAC National Accelerator Laboratory, corresponding to
million pairs. We find the CP-violation parameter values and
branching fractions where in each case, the first uncertainties are statistical
and the second are systematic. We observe CP violation with a significance of
6.7 standard deviations for and 6.1 standard deviations for
, including systematic uncertainties. Constraints on the
Unitarity Triangle angle are determined from the isospin relations
among the rates and asymmetries. Considering only the solution
preferred by the Standard Model, we find to be in the range
at the 68% confidence level.Comment: 18 pages, 11 postscript figures, submitted to Phys. Rev.
Measurement of Branching Fractions and Rate Asymmetries in the Rare Decays B -> K(*) l+ l-
In a sample of 471 million BB events collected with the BABAR detector at the
PEP-II e+e- collider we study the rare decays B -> K(*) l+ l-, where l+ l- is
either e+e- or mu+mu-. We report results on partial branching fractions and
isospin asymmetries in seven bins of di-lepton mass-squared. We further present
CP and lepton-flavor asymmetries for di-lepton masses below and above the J/psi
resonance. We find no evidence for CP or lepton-flavor violation. The partial
branching fractions and isospin asymmetries are consistent with the Standard
Model predictions and with results from other experiments.Comment: 16 pages, 14 figures, accepted by Phys. Rev.
Recommended from our members
Measurement of B(B-->X_s {\gamma}), the B-->X_s {\gamma} photon energy spectrum, and the direct CP asymmetry in B-->X_{s+d} {\gamma} decays
The photon spectrum in B --> X_s {\gamma} decay, where X_s is any strange
hadronic state, is studied using a data sample of (382.8\pm 4.2) \times 10^6
e^+ e^- --> \Upsilon(4S) --> BBbar events collected by the BABAR experiment at
the PEP-II collider. The spectrum is used to measure the branching fraction B(B
--> X_s \gamma) = (3.21 \pm 0.15 \pm 0.29 \pm 0.08)\times 10^{-4} and the
first, second, and third moments = 2.267 \pm 0.019 \pm 0.032 \pm
0.003 GeV,, )^2> = 0.0484 \pm 0.0053 \pm 0.0077 \pm
0.0005 GeV^2, and )^3> = -0.0048 \pm 0.0011 \pm 0.0011
\pm 0.0004 GeV^3, for the range E_\gamma > 1.8 GeV, where E_{\gamma} is the
photon energy in the B-meson rest frame. Results are also presented for
narrower E_{\gamma} ranges. In addition, the direct CP asymmetry A_{CP}(B -->
X_{s+d} \gamma) is measured to be 0.057 \pm 0.063. The spectrum itself is also
unfolded to the B-meson rest frame; that is the frame in which theoretical
predictions for its shape are made.Comment: 37 pages, 19 postscript figures, submitted to Phys. Rev. D. No
analysis or results have changed from previous version. Some changes to
improve clarity based on interactions with Phys. Rev. D referees, including
one new Figure (Fig. 13), and some minor wording/punctuation/spelling
mistakes fixe
Cross Sections for the Reactions e+e- --> K+ K- pi+pi-, K+ K- pi0pi0, and K+ K- K+ K- Measured Using Initial-State Radiation Events
We study the processes e+e- --> K+ K- pi+pi-gamma, K+ K- pi0pi0gamma, and K+
K- K+ K-gamma, where the photon is radiated from the initial state. About
84000, 8000, and 4200 fully reconstructed events, respectively, are selected
from 454 fb-1 of BaBar data. The invariant mass of the hadronic final state
defines the \epem center-of-mass energy, so that the K+ K- pi+pi- data can be
compared with direct measurements of the e+e- --> K+ K- pi+pi- reaction. No
direct measurements exist for the e+e- --> K+ K-pi0pi0 or e+e- --> K+ K-K+ K-
reactions, and we present an update of our previous result with doubled
statistics. Studying the structure of these events, we find contributions from
a number of intermediate states, and extract their cross sections. In
particular, we perform a more detailed study of the e+e- --> phi(1020)pipigamma
reaction, and confirm the presence of the Y(2175) resonance in the phi(1020)
f0(980) and K+K-f0(980) modes. In the charmonium region, we observe the J/psi
in all three final states and in several intermediate states, as well as the
psi(2S) in some modes, and measure the corresponding product of branching
fraction and electron width.Comment: 35 pages, 42 figure
Recommended from our members
Precise Measurement of the e+ e- --> pi+ pi- (gamma) Cross Section with the Initial-State Radiation Method at BABAR
A precise measurement of the cross section of the process
from threshold to an energy of 3GeV is obtained
with the initial-state radiation (ISR) method using 232fb of data
collected with the BaBar detector at center-of-mass energies near
10.6GeV. The ISR luminosity is determined from a study of the leptonic process
, which is found to agree with the
next-to-leading-order QED prediction to within 1.1%. The cross section for the
process is obtained with a systematic uncertainty
of 0.5% in the dominant resonance region. The leading-order hadronic
contribution to the muon magnetic anomaly calculated using the measured
cross section from threshold to 1.8GeV is .Comment: 58 pages, 56 figures, to be submitted to Phys. Rev.
Observation of time-reversal violation in the B0 meson system
The individually named authors work collectively as The BABAR Collaboration. Copyright @ 2012 American Physical Society.Although CP violation in the B meson system has been well established by the B factories, there has been no direct observation of time-reversal violation. The decays of entangled neutral B mesons into definite flavor states (B0 or B¯¯¯0), and J/ψK0L or cc¯K0S final states (referred to as B+ or B−), allow comparisons between the probabilities of four pairs of T-conjugated transitions, for example, B¯¯¯0→B− and B−→B¯¯¯0, as a function of the time difference between the two B decays. Using 468×106 BB¯¯¯ pairs produced in Υ(4S) decays collected by the BABAR detector at SLAC, we measure T-violating parameters in the time evolution of neutral B mesons, yielding ΔS+T=−1.37±0.14(stat)±0.06(syst) and ΔS−T=1.17±0.18(stat)±0.11(syst). These nonzero results represent the first direct observation of T violation through the exchange of initial and final states in transitions that can only be connected by a T-symmetry transformation.DOE and NSF (USA), NSERC (Canada), CEA and CNRS-IN2P3 (France), BMBF and
DFG(Germany), INFN (Italy), FOM (The Netherlands),
NFR (Norway), MES (Russia), MINECO (Spain), STFC
(United Kingdom). Individuals have received support from
the Marie Curie EIF (European Union), the A. P. Sloan
Foundation (USA) and the Binational Science Foundation
(USA-Israel)
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