Consequences of strong fluctuations on high-energy QCD evolution

We investigate the behaviour of the QCD evolution towards high-energy, in the diffusive approximation, in the limit where the fluctuation contribution is large. Our solution for the equivalent stochastic Fisher equation predicts the amplitude as well as the whole set of correlators in the strong noise limit. The speed of the front and the diffusion coefficient are obtained. We analyse the consequences on high-energy evolution in QCD.Comment: 5 pages, 1 figure, more detailed discussions added, version to appear in Phys. Rev.

Exclusive vector meson production at HERA from QCD with saturation

Following recent predictions that the geometric scaling properties of deep inelastic scattering data in inclusive gamma*-p collisions are expected also in exclusive diffractive processes, we investigate the diffractive production of vector mesons. Using analytic results in the framework of the BK equation at non-zero momentum transfer, we extend to the non-forward amplitude a QCD-inspired forward saturation model including charm, following the theoretical predictions for the momentum transfer dependence of the saturation scale. We obtain a good fit to the available HERA data and make predictions for deeply virtual Compton scattering measurements.Comment: 10 pages, 5 figures, full analysis including the charm contribution and J/PSI production. Conclusions confirme

Vif is a RNA chaperone that could temporally regulate RNA dimerization and the early steps of HIV-1 reverse transcription

HIV-1 Vif (viral infectivity factor) is associated with the assembly complexes and packaged at low level into the viral particles, and is essential for viral replication in non-permissive cells. Viral particles produced in the absence of Vif exhibit structural defects and are defective in the early steps of reverse transcription. Here, we show that Vif is able to anneal primer tRNALys3 to the viral RNA, to decrease pausing of reverse transcriptase during (–) strand strong-stop DNA synthesis, and to promote the first strand transfer. Vif also stimulates formation of loose HIV-1 genomic RNA dimers. These results indicate that Vif is a bona fide RNA chaperone. We next studied the effects of Vif in the presence of HIV-1 NCp, which is a well-established RNA chaperone. Vif inhibits NCp-mediated formation of tight RNA dimers and hybridization of tRNALys3, while it has little effects on NCp-mediated strand transfer and it collaborates with nucleocapsid (NC) to increase RT processivity. Thus, Vif might negatively regulate NC-assisted maturation of the RNA dimer and early steps of reverse transcription in the assembly complexes, but these inhibitory effects would be relieved after viral budding, thanks to the limited packaging of Vif in the virions

ЗНАХІДКИ УКРАЇНСЬКИХ НАТІЛЬНИХ ХРЕСТІВ В СЕРЕДНЬОМУ І НИЖНЬОМУ ПРИСАМАР’Ї

Територія Пониззя Присамар’я здавна привертала увагу дослідників, проте їх зацікавленість належала, переважно археологічним пам’яткам від доби каменю – бронзи та ранньозалізного часу. Пам’ятки пізніших часів, тим більш козацької епохи, переважно залишалися поза вивченням [28, с.28, 29- 33 с.214]. Винятковим явищем у цьому плані є роботи керованої Д.І.Яворницьким новобудівної Дніпрогесівської експедиції НКПросу 1927-1932 років [14, с.11-12], коли вперше на зазначених територіях були відкриті і досліджувалися не лише неолітичні і матеріали ранньобронзової доби, а й алано-болгарські пам’ятки, поселення доби Київської Русі, козацькі поховання XVII-XVIII ст. Д.І.Яворницький першим проводив археологічні розвідки на теренах Богородицької фортеці і її посаду під час робіт Дніпрогесівської експедиції 1927-1932 років [13; 19, с. 256-257] (у фондах ДІМ ім. Д.І.Яворницького знаходиться близько 80 натільних хрестів «із запорозьких поховань», зібраних вченим, але у матеріалах його розвідок місця знахідок часто не фіксувалися, через це знахідки не паспортизовувалися, що ускладнює ідентифікацію матеріалів). У повоєнні роки і до кінця 1980-х матеріали доби середньовіччя і козаччини з гирла Самари цікавили, переважно, краєзнавців і аматорів. У 1960-1970 рр. брати В.В. та Е.В.Бінкевичі знаходили монети й інші старожитності на Ігренському півострові: про ці знахідки з пониззя Самари лише стисло згадано в праці „Городок старинный запорожский Самарь с перевозом [1]. В цей же час і на цій же території краєзнавець з Придніпровська Є.Богуш збирав натільні хрести, колекція яких по смерті аматора була розпродана спадкоємцями частинами. У 2001 році науково-дослідною Лабораторією археології Подніпров’я ДНУ під керівництвом професора І.Ф.Ковальової на території Богородицьком фортеці і її посаду були розпочаті планомірні розвідки і розкопки

Synergistic effects of TNF-alpha and melphalan in an isolated limb perfusion model of rat sarcoma: a histopathological, immunohistochemical and electron microscopical study.

Isolated limb perfusion (ILP) with tumour necrosis factor alpha (TNF-alpha) and melphalan has shown impressive results in patients with irresectable soft tissue sarcomas and stage III melanoma of the extremities. The mechanisms of the reported in vivo synergistic anti-tumour effects of TNF-alpha and melphalan are not precisely understood. We have developed an ILP model in the rat using a non-immunogenic sarcoma in which similar in vivo synergy is observed. The aim of this present study was to analyse the morphological substrate for this synergistic response of TNF-alpha in combination with melphalan to shed more light on the pathomechanisms involved. Histology of the tumours from saline- (n = 14) and melphalan-treated (n = 11) rats revealed apparently vital tumour cells in over 80% of the cross-sections. Interstitial oedema and coagulation necrosis were observed in the remaining part of the tumour. Haemorrhage was virtually absent. TNF-alpha (n = 22) induced marked oedema, hyperaemia, vascular congestion, extravasation of erythrocytes and haemorrhagic necrosis (20-60% of the cross-sections). Oedema and haemorrhage suggested drastic alterations of permeability and integrity of the microvasculature. Using light and electron-microscopy, we observed that haemorrhage preceded generalised platelet aggregation. Therefore, we suggest that the observed platelet aggregation was the result of the microvascular damage rather than its initiator. Remarkably, these events hardly influenced tumour growth. However, perfusion with the combination of TNF-alpha and melphalan (n = 24) showed more extensive haemorrhagic necrosis (80-90% of the cross-sections) and revealed a prolonged remission (mean 11 days) in comparison with the other groups of rats. Electron microscopical analysis revealed similar findings as described after TNF-alpha alone, although the effects were more prominent at all time points after perfusion. In conclusion, our findings suggest that the enhanced anti-tumour effect after the combination of TNF-alpha with melphalan results from potentiation of the TNF-alpha-induced vascular changes accompanied by increased vascular permeability and platelet aggregation. This may result in additive cytotoxicity or inhibition of growth of residual tumour cells

Possible background reductions in double beta decay experiments

The background induced by radioactive impurities of $^{208}\rm Tl$ and $^{214}\rm Bi$ in the source of the double beta experiment NEMO-3 has been investigated. New methods of data analysis which decrease the background from the above mentioned contamination are identified. The techniques can also be applied to other double beta decay experiments capable of measuring independently the energies of the two electrons.Comment: 15 pages, 13 figures, accepted in the Nuclear Instruments and Methods

The distribution of the species of the genus Deroceras Rafinesque, 1820 in Belgium (Gastropoda, Pulmonata, Agriolimacidae)

Four species belonging to the genus Deroceras are known from Belgium: D. reticulatum /MÜLLER, 1774/, D. laeve /MÜLLER, 1774/, D. caruanae /POLLONERA, 1891/ and D. agreste /LINNAEUS, 1758/. The distribution of D. reticulatum, P. laeve and D. caruanae as known at the end of 1971 is compared with a map showing all records of landsnail species in Belgium till then. A similar comparison is given for the year 1982. From the period 1972-1982 year to year maps- showing all records of each of these three Deroceras species are compared with a corresponding map compiling all landsnail records of the same year. At present P.reticulatum,D.laeve and D. caruanae are very widespread and common. D. caruanae was found for the first time in Belgium in 1968. As shown by means of a series of cumulative maps, D. caruanae became very rapidly widespread /1973 onwards/ presenting an explosive dispersal. Undoubtedly,man assisted in its introduction and dispersal. P. agreste seems to be very rare in Belgium with a limited number of local populations in the four southern provinces