We study the process e + e − → e + e − η ′ in the double-tag mode and measure for the first time the γ * γ * → η ′ transition form factor F η′ ( Q 2 1 , Q 2 2 ) in the momentum-transfer range 2 < Q 2 ...1 , Q 2 2 < 60 GeV 2 . The analysis is based on a data sample corresponding to an integrated luminosity of around 469 fb − 1 collected at the PEP-II e + e − collider with the BABAR detector at center-of-mass energies near 10.6 GeV.
We study the process e+e−→π+π−ηγ, where the photon is radiated from the initial state. About 8000 fully reconstructed events of this process are selected from the BABAR data sample with an integrated ...luminosity of 469 fb−1. Using the π+π−η invariant mass spectrum, we measure the e+e−→π+π−η cross section in the e+e− center-of-mass energy range from 1.15 to 3.5 GeV. The cross section is well described by the Vector-Meson dominance model with four ρ-like states. We observe 49±9 events of the J/ψ decay to π+π−η and measure the product ΓJ/Ψ→e+e−BJ/Ψ→π+π−η=2.34±0.43stat±0.16syst eV.
Insufficient information on the characteristics of changes in nutrients of Sudan grass according to the phases of growth and development is one of the main obstacles to the widespread use of this ...crop in feed production. The purpose of the study is to analyze changes in the content of protein and dry matter in green mass of Sudan grass varieties during a vegetation period depending on the sowing method. The research was carried out in the Rostov region on ordinary carbonate chernozem. The growing seasons were characterized by a contrasting hydrothermal regime: in 2022 – average aridity, in 2021 and 2023. – insufficient hydration. The objects of the study were the Sudan grass varieties ‘Aleksandrina’, ‘Alisa’, ‘Gratsiya’, ‘Kudesnitsa’ bred by the Agricultural Research Center “Donskoy”. With the row sowing method (row spacing 15 cm, seeding rate 1.6 million pcs/ha), a more rapid accumulation of dry matter occurs in all studied varieties at the beginning of the vegetation period. By the end of the vegetation period, the dry matter content is higher with wide-row sowing (70 cm row spacing, 340 thousand pieces/ha), by 4.21% on average among the varieties. Rapid accumulation of dry matter was noted from the end of the “heading” phase up to the “milk ripeness” phase. The protein content in dry matter with wide-row sowing at the beginning of the growing season was two times higher than with continuous sowing and amounted to 21.33–24.17 %. Starting from the “heading” phase, the value of the trait decreased sharply and by the time of full grain ripeness it was 5.17–6.74 % for row sowing and 8.01–8.61 % for wide-row sowing. This change in protein in the dry matter of green mass indicates the practicability of using the crop in early stages of the vegetation period to obtain the best feed quality.
This article reveals the relevance of the development of production of clad plates and large-diameter pipes in Russia. The most widespread technologies in the world are compared. The results of the ...mathematical and physical modeling of the rolling of bimetallic packs into strips are described. The use of pack rolled clad plates is shown to be preferable for the production of large-diameter electric-welded pipes. The main production aspects of clad plates from a pack billet on a plate mill and their resulting pipes are presented.
The geographic distribution and parasitic associations of the louse
Polyplax hannswrangeli
in West Siberia are described. This louse has been recorded on 8 species of small mammals. The hosts most ...strongly associated with this louse were determined. Infestation with
P. hannswrangeli
was recorded for the first time for 5 species of small mammals in the forest zone of West Siberia: the common shrew, Siberian chipmunk, Eurasian water vole, East European vole, and root vole. In West Siberia,
P. hannswrangeli
was found only in the forest-tundra and forest zones. Its mean population density in the northern taiga of West Siberia was twice as high as that in the forest-tundra and middle taiga zones.
Users' demand in computer power and rise of technology favour the arrival of Grid systems. The quality of Grid systems' performance depends on computer and time resources scheduling. Grid systems ...with a centralized structure of the scheduling system and user's task are modeled by resource quadrant and re-source rectangle accordingly. A Non-Euclidean heuristic measure, which takes into consideration both the area and the form of an occupied resource region, is used to estimate scheduling quality of heuristic algorithms. The authors use sets, which are induced by the elements of square squaring, as an example of studying the adapt-ability of a level polynomial algorithm with an excess and the one with minimal deviation.
Using the initial-state radiation method, the e + e − → KSKL cross section from 1.98 to 2.54 GeV is measured in a data sample of 469 fb −1 collected with the BABAR detector. The results are used in ...conjunction with previous BABAR results for the e + e − → K + K − , e + e − → π + π − , e + e − → π + π − η , and e + e − → ω π π cross sections to investigate the nature of the resonance structure recently observed by the BESIII experiment in the e + e − → K+K− cross section.
Lice (Anoplura) were studied in 2015–2018 in the middle taiga of West Siberia in the territory of the Middle Ob region (Khanty-Mansi Autonomous Okrug–Yugra). Lice were found on 15 species of small ...mammals, of which the most significant hosts were
Alexandromys oeconomus
,
Microtus rossiaemeridionalis
,
M. agrestis
,
Myodes glareolus
, and
M. rutilus
. The louse
Hoplopleura acanthopus
had the widest host range and was also dominant among all the louse species found on small mammals. The peaks of louse abundance coincided with those of host reproductive activity in late spring and early autumn. In the most common host
A. oeconomus
, the highest degree of infestation (mainly with
H. acanthopus
) was recorded in adult males; the corresponding indices were significantly lower in adult females and especially low in young mammals. The population structure of
H. acanthopus
showed prevalence of females (about 50%) in comparison with males and larvae. Co-parasitism of lice was especially pronounced on adult host specimens. The lice
Hoplopleura edentula
,
Hoplopleura longula
, and
Polyplax hannswrangeli
were recorded for the first time from the studied territory.
We present searches for rare or forbidden charm decays of the form X + c → h ± ℓ ∓ ℓ ( ' ) + , where X + c is a charm hadron ( D + , D + s , or Λ + c ), h ± is a pion, kaon, or proton, and ℓ ( ' ) ± ...is an electron or muon. The analysis is based on 384 fb − 1 of e + e − annihilation data collected at or close to the Υ ( 4 S ) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. No significant signal is observed for any of the 35 decay modes that are investigated. We establish 90% confidence-level upper limits on the branching fractions between 1 × 10 − 6 and 44 × 10 − 6 depending on the channel. In most cases, these results represent either the first limits or significant improvements on existing limits for the decay modes studied.
Multipotent mesenchymal stromal cells (MSC) are the key regulators of hematopoiesis. We studied changes in MSC characteristics in patients with myeloid leukemia and patients with lymphoproliferative ...diseases. MSC were obtained from the bone marrow of patients at the time of diagnostic puncture using a standard technique. Their proliferative potential and expression of genes associated with differentiation and regulation of hematopoiesis were studied. The total cell production of MSC in patients with leukemia at the onset of the disease did not differ from that in the group of healthy donors. The relative expression of the
IL6
,
TGFb1
and
TGFb2
,
PPARG
genes was similar in all patients. The relative expression of the
JAG1
,
LIF
,
IGF1
,
CSF1
,
IL1b
, and
IL1bR1
genes in MSC of patients with leukemia was enhanced and the relative expression of
SDF1
was unchanged in comparison with MSC from donors. MSC from patients with leukemia were characterized by enhanced relative expression of
PDGFRA
and
PDGFRB
, and reduced expression of
SOX9
. Changes functions of the stromal microenvironment in patients with hemoblastoses attested to the role of stromal cells in the maintenance and spread of tumor cells.
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