Vascular Endothelial Growth Factor-Related Pathways in Hemato-Lymphoid Malignancies

Angiogenesis is essential for malignant tumor growth. This has been documented for solid tumors, and there is an emerging evidence suggesting that tumor progression of hematolymphoid malignancies also depends on the induction of new blood vessel formation. The most important proangiogenic agent is vascular endothelial growth factor (VEGF), activating VEGF receptors 1 and 2. The available data on angiogenesis in hemato-lymphoid malignancies, such as acute leukemias, myelodysplastic syndromes, myeloproliferative neoplasms, multiple myeloma, and lymphomas, point towards the significance of autocrine and paracrine VEGF-mediated effects for proliferation and survival of leukemia/lymphoma cells in addition to tumor vascularization. Antiangiogenic strategies have become an important therapeutic modality for solid tumors. Several antiangiogenic agents targeting VEGF-related pathways are also being utilized in clinical trials for the treatment of hemato-lymphoid malignancies, and in some instances these pathways have emerged as promising therapeutic targets. This review summarizes recent advances in the basic understanding of the role of angiogenesis in hemato-lymphoid malignancies and the translation of such basic findings into clinical studies

Color Transparency Effects in Electron Deuteron Interactions at Intermediate Q^2

High momentum transfer electrodisintegration of polarized and unpolarized deuterium targets, $d(e,e'p)n$ is studied. We show that the importance of final state interactions-FSI, occuring when a knocked out nucleon interacts with the other nucleon, depends strongly on the momentum of the spectator nucleon. In particular, these FSI occur when the essential contributions to the scattering amplitude arise from internucleon distances $\sim 1.5~fm$. But the absorption of the high momentum $\gamma^*$ may produce a point like configuration, which evolves with time. In this case, the final state interactions probe the point like configuration at the early stage of its evolution. The result is that significant color transparency effects, which can either enhance or suppress computed cross sections, are predicted to occur for $\sim 4 GeV^2 \ge Q^2\leq~10~(GeV/c)^2$.Comment: 37 pages LaTex, 12 uuencoded PostScript Figures as separate file, to be published in Z.Phys.

Torsion action and its possible observables

The methods of effective field theory are used to explore the theoretical and phenomenological aspects of the torsion field. Spinor action coupled to electromagnetic field and torsion possesses an additional softly broken gauge symmetry. This symmetry enables one to derive the unique form of the torsion action compatible with unitarity and renormalizability. It turns out that the antisymmetric torsion field is equivalent to an massive axial vector field. The introduction of scalars leads to serious problems which are revealed after the calculation of the leading two-loop divergences. Thus the phenomenological aspects of torsion may be studied only for the fermion-torsion systems. In this part of the paper we obtain an upper bounds for the torsion parameters using present experimental data on forward-backward Z-pole asymmetries, data on the experimental limits on four-fermion contact interaction (LEP, HERA, SLAC, SLD, CCFR) and also TEVATRON limits on the cross section of new gauge boson, which could be produced as a resonance at high energy $p\bar{p}$ collisions. The present experimental data enable one to put the limits on torsion parameters for the various range of the torsion mass. We emphasize that for the torsion mass of the order of the Planck mass no any independent theory for torsion is possible, and one must directly use string theory.Comment: 24 pages, LaTex, 5 figure

Limits on the production of scalar leptoquarks from Z (0) decays at LEP

A search has been made for pairs and for single production of scalar leptoquarks of the first and second generations using a data sample of 392000 Z0 decays from the DELPHI detector at LEP 1. No signal was found and limits on the leptoquark mass, production cross section and branching ratio were set. A mass limit at 95% confidence level of 45.5 GeV/c2 was obtained for leptoquark pair production. The search for the production of a single leptoquark probed the mass region above this limit and its results exclude first and second generation leptoquarks D0 with masses below 65 GeV/c2 and 73 GeV/c2 respectively, at 95% confidence level, assuming that the D0lq Yukawa coupling alpha(lambda) is equal to the electromagnetic one. An upper limit is also given on the coupling alpha(lambda) as a function of the leptoquark mass m(D0)

From soft to superhard: Fifty years of experiments on cold-compressed graphite

In recent years there have been numerous computational studies predicting the nature of cold-compressed graphite yielding a proverbial alphabet soup of carbon structures (e.g., bct-C4, K4-, M-, H-, R-, S-, T-, W- and Z-carbon). Although theoretical methods have improved, the inherent nature of graphite (i.e., low-Z) and the subsequent room-temperature, high-pressure phase transition (i.e., low symmetry, nanocrystalline and sluggish), make experimental measurements difficult to execute and interpret even with the current technology of 3rd generation synchrotron sources. The room-temperature, high-pressure phase transition of graphite has been detected by numerous kinds of experiments over the past fifty years, such as electrical resistance measurements, optical microscopy, X-ray diffraction, inelastic X-ray scattering, and Raman spectroscopy. However, the identification and characterization of high-pressure graphite is replete with controversy since its discovery more than fifty years ago. Recent experiments confirm that this phase has a monoclinic structure, consistent with the M-carbon phase predicted by theoretical computations. Meanwhile, experiments demonstrate that the phase transition is sluggish and kinetics is important in discerning the phase boundary. Additionally, the post-graphite phase appears to be superhard with hardness comparable to that of diamond.В останні роки було проведено велику кількість чисельних досліджень, що прогнозують основні властивості графіту, підданого стисненню при кімнатній температурі, в результаті чого виникає загальновідомий “алфавітний суп” з вуглецевих структур (наприклад, bct-C₄, K₄-, M- , H-, R-, S-, T-, W-і Z-вуглець). Тоді як теоретичні методи стали більш досконалими, природа, притаманна графіту (тобто низьке Z), і подальший фазовий перехід при кімнатній температурі і високому тиску (низькосиметричний, нанокристалічний і млявий) роблять експериментальні вимірювання важко здійсненними і їх складно інтерпретувати навіть із застосуванням сучасної технології, що використовує 3-е покоління синхротронних джерел. За минулі 50 років фазовий перехід графіту при кімнатній температурі і високому тиску був виявлений багатьма видами експериментів, таких як вимірювання електроопору, оптична мікроскопія, дифракція рентгенівських променів, непружне розсіювання рентгенівських променів і раманівська спектроскопія. Однак з дня його відкриття більше 50 років тому ідентифікація та отримані характеристики графіту високого тиску повні суперечностей. Недавні експерименти підтверджують, що ця фаза має моноклинну структуру, узгоджується з М-вуглецевої фазою, передбаченою теоретичними розрахунками. Поки експерименти демонструють, що фазовий перехід є повільним, а при розпізнаванні фазових границь важливе значення має кінетика процесу. Крім того, пост-графітова фаза є надтвердою, за твердістю близькою до алмазу.В последние годы было проведено большое количество численных исследований, предсказывающих основные свойства графита, подвергнутого сжатию при комнатной температуре, в результате чего возникает пресловутый “алфавитный суп” из углеродных структур (например, bct-C₄, K₄-, M-, H-, R-, S-, T-, W- и Z-углерод). В то время как теоретические методы стали более совершенными, природа, присущая графиту (т. е. низкое Z), и последующий фазовый переход при комнатной температуре и высоком давлении (низкосимметричный, нанокристаллический и вялый) делают экспериментальные измерения трудно выполнимыми и их сложно интерпретировать даже с применением современной технологии, использующей 3-е поколение синхротронных источников. За прошедшие 50 лет фазовый переход графита при комнатной температуре и высоком давлении был обнаружен многими видами экспериментов, таких как измерения электросопротивления, оптическая микроскопия, дифракция рентгеновских лучей, неупругое рассеяние рентгеновских лучей и рамановская спектроскопия.. Однако со дня его открытия более 50 лет назад идентификация и полученные характеристики графита высокого давления полны противоречий. Недавние эксперименты подтверждают, что эта фаза имеет моноклинную структуру, согласующуюся с М-углеродной фазой, предсказанной теоретическими расчетами. Пока эксперименты демонстрируют, что фазовый переход является медленным, а при распознавании фазовых границ важное значение имеет кинетика процесса. Кроме того, пост-графитовая фаза является сверхтвердой, по твердости близкой алмазу

Midrapidity ϕ\phi production in Au+Au collisions at SNN\sqrt{S_{NN}} = 130 GeV

We report results on the ratio of midrapidity antiproton-to-proton yields in Au + Au collisions at roots(NN) = 130 GeV per nucleon pair as measured by the STAR experiment at RHIC. Within the rapidity and transverse momentum range of /y/ < 0.5 and 0.4 < p(i) < 1.0 GeV/c, the ratio is essentially independent of either transverse momentum or rapidity, with an average of 0.65 <plus/minus> 0.01((stat)) +/- 0.07((syst)) for minimum bias collisions. Within errors, no strong centrality dependence is observed. The results indicate that at this RHIC energy, although the p-(p) over bar pair production becomes important at midrapidity, a significant excess of baryons: over antibaryons is still present

Evidence for B(s)0 meson production in Z0 decays

Seven unambiguous events out of a sample of 270 000 Z0 decays, contain in the same jet a Ds meson and a muon at large transverse momentum relative to the jet axis. These events are direct evidence for Bs 0 meson production in hadronic Z0 decays. The production rate of these events, relative to all hadronic Z0 decays is (18 ± 8) × 10-5, this number including the relevant branching fractions of the Bs 0 and Ds. The value of the Bs 0 meson lifetime relative to the average B meson lifetime is measured to be 0.8 ± 0.4.0SCOPUS: ar.jinfo:eu-repo/semantics/publishe