Effects of soft gluon emission on the opposite-side acollinearity distributions in e+e- annihilation

Baier R, Fey K. Effects of soft gluon emission on the opposite-side acollinearity distributions in e+e- annihilation. Nuclear physics B. 1981;179(1):49-61

The VLBA Calibrator Search for the BeSSeL Survey

We present the results of a survey of radio continuum sources near the Galactic plane using the Very Long Baseline Array (VLBA). Our observations are designed to identify compact extragalactic sources of milliarcsecond size that can be used for parallax measurements in the Bar and Spiral Structure Legacy Survey. We selected point sources from the NVSS and CORNISH catalogs with flux densities above 30 mJy and within 1.5\degr of known maser targets. Of the 1529 sources observed, 199 were detected. For sources detected on 3 or more baselines, we determined accurate positions and evaluated their quality as potential calibrators. Most of the 1330 sources that were not detected with the VLBA are probably of extragalactic origin.Comment: 27 pages, 3 figures, 3 tables. Table 3 is available on the homepage of the BeSSeL survey: http://www.mpifr-bonn.mpg.de/staff/abrunthaler/BeSSeL/index.shtm

Proline biosynthesis regulates proline transport in Staphylococcus aureus.

Staphylococcus aureus is metabolically diverse with the ability to rapidly adapt to a vast array of nutrient sources. This allows the pathogen to colonize a variety of niches in the host. For instance, S. aureus is the leading cause of skin and soft tissue infections, a niche that has been shown to become glucose-depleted over the course of an infection. Previous studies have shown that in niches where glucose is deficient, S. aureus utilizes peptides and free amino acids as nutrient sources. Primarily, these amino acids include glutamate and amino acids that can serve as substrates for glutamate synthesis. While arginine and histidine serve as substrates in glutamate synthesis, proline is the primary source of glutamate. Indeed, S. aureus utilizes proline as a secondary carbon source only when glucose is absent, and it can be synthesized from arginine or acquired via proline transporters from its environment. Although S. aureus encodes two putative pathways for proline biosynthesis, it has been shown that pyrroline-5-carboxylate reductase (encoded by proC) is the sole proline biosynthetic pathway in S. aureus. Studies from our laboratory have revealed that despite encoding five putative proline transporters (B7H15_03660, opuC, opuD, proP, putP), only two of the transporters, PutP and B7H15_03660 are responsible for a majority of proline transport under the laboratory conditions tested. Surprisingly, when we introduced the proC mutation into the B7H15_03660 putP double mutant, we observed proline-dependent growth, even though the primary proline transporters and proline biosynthetic pathway were knocked-out. In contrast, a transporter null ΔproC strain was unable to grow. These data suggest that inhibiting proline biosynthesis alters proline transport, and therefore one or more of the additional transporters, OpuC, OpuD, and/or ProP, are activated under these conditions. After introducing opuC, opuD, and/or proP mutations into the Δ03660 ΔputP ΔproC strain, we found that both OpuC and ProP are important for proline transport. Additionally, we observed proline-dependent growth in a proline transporter null ΔproC strain when high amounts of exogenous proline are added to the media. This growth appears to be due to an acquired mutation and will be studied more in the future. Overall these studies have revealed that proline transport is tightly linked to proline biosynthesis.https://digitalcommons.unmc.edu/surp2021/1021/thumbnail.jp

Проблемы ипотечного кредитования в России на современном этапе

По мере развития в России банковского сектора большую популярность приобрели ипотечные кредиты. Данный вопрос является актуальным в наши дни, так как многие взрослые люди хоть раз задумывались о возможностях использования данного банковского продукта. У ипотеки, как и у других форм кредитования, есть свои плюсы и минусы, хотя люди, задумываясь о приобретении собственного жилья, все же останавливаются на выборе ипотечного кредитования

The distance to a star forming region in the Outer arm of the Galaxy

We performed astrometric observations with the VLBA of WB89-437, an H2O maser source in the Outer spiral arm of the Galaxy. We measure an annual parallax of 0.167 +/- 0.006 mas, corresponding to a heliocentric distance of 6.0 +/- 0.2 kpc or a Galactocentric distance of 13.4 +/- 0.2 kpc. This value for the heliocentric distance is considerably smaller than the kinematic distance of 8.6 kpc. This confirms the presence of a faint Outer arm toward l = 135 degrees. We also measured the full space motion of the object and find a large peculiar motion of ~20 km/s toward the Galactic center. This peculiar motion explains the large error in the kinematic distance estimate. We also find that WB89-437 has the same rotation speed as the LSR, providing more evidence for a flat rotation curve and thus the presence of dark matter in the outer Galaxy.Comment: The Astrophysical Journal, accepted, 16 pages, 4 Figure