Molecular characterization of a high A2 beta thalassemia by direct sequencing of single strand enriched amplified genomic DNA

Two families, one of Anglo-Saxon-Dutch descent, and the other, West Indian black, have an atypical beta thalassemia characterized by an unusually high level of Hb A2 in the heterozygous state. Restriction endonuclease mapping showed a deletion of about 1.35 kilobase (kb) in the 5' region of the beta globin gene. Direct sequencing of a specific region of genomic DNA amplified by a new modification of the polymerase chain reaction defined the deletion to be 1,393 base pairs (bp) and to be the same in both families. The deletion extends from 485 bp 5' to the mRNA CAP site to the middle of the second intervening sequence. This deletion, together with three others previously described that remove the 5' end of the beta gene but leave the delta gene intact, are all associated with unusually high levels of Hb A2 in the heterozygous state.     

Small-scale universality in fluid turbulence

Turbulent flows in nature and technology possess a range of scales. The largest scales carry the memory of the physical system in which a flow is embedded. One challenge is to unravel the universal statistical properties that all turbulent flows share despite their different large-scale driving mechanisms or their particular flow geometries. In the present work, we study three turbulent flows of systematically increasing complexity. These are homogeneous and isotropic turbulence in a periodic box, turbulent shear flow between two parallel walls, and thermal convection in a closed cylindrical container. They are computed by highly resolved direct numerical simulations of the governing dynamical equations. We use these simulation data to establish two fundamental results: (i) at Reynolds numbers Re ∼ 10² the fluctuations of the velocity derivatives pass through a transition from nearly Gaussian (or slightly sub-Gaussian) to intermittent behavior that is characteristic of fully developed high Reynolds number turbulence, and (ii) beyond the transition point, the statistics of the rate of energy dissipation in all three flows obey the same Reynolds number power laws derived for homogeneous turbulence. These results allow us to claim universality of small scales even at low Reynolds numbers. Our results shed new light on the notion of when the turbulence is fully developed at the small scales without relying on the existence of an extended inertial range.An enduring notion in the phenomenology of turbulence is the universality of small scales. It has been taken for granted in theoretical approaches (e.g., refs. 1–8) and analyzed in numerical simulations (9–11) as well as various laboratory experiments (e.g., refs. 5 and 12). The standard paradigm is that whereas the large scales are nonuniversal, reflecting the circumstances of their generation, an increasingly weaker degree of nonuniversality is imparted to small scales with increasing separation between the large and small scales. This scale separation is thought to increase with the flow Reynolds number, so a proper test of universality has been thought to require very high Reynolds numbers. Consequently, many substantial efforts have been made to produce such high-Reynolds-number flows (e.g., ref. 12).Here, we show evidence for an alternative point of view: If one resolves small scales accurately, one observes, even at low Reynolds numbers, universal scaling of velocity gradients that manifest primarily at small scales. We stress that small-scale dynamics are strongly nonlinear even in low-Reynolds-number flows driven by large-scale forcing. There is thus considerable merit in measuring or simulating low-Reynolds-number flows much more accurately than has been the practice and exploring the evidence for universality (or lack thereof), instead of advancing as inevitable the notion that useful lessons about universality are possible only at very high Reynolds numbers. Indeed, another result of this paper is that there exists a threshold Reynolds number above which Gaussian-like fluctuations tend to assume intermittent characteristics of fully developed flows and that these features can be extracted by accessing increasingly smaller scales even if the Reynolds numbers are quite moderate. The latter result is especially important for purposes of identifying a fixed point in certain renormalization group expansion procedures (8).     

Development of methods for the analysis of the new sterically hindered phenol dibornol as a pharmaceutical substance

Methods for monitoring the quality of the new pharmaceutical substance 4-methyl-2,6-diisobornylphenol (dibornol) were developed.     

Reactions of delayed hypersensitivity in patients with tuberculosis in its dormancy and pandemic

Comparison of the results of tuberculin diagnosis in patients with tuberculosis during two studies made by the same procedure in 1973 and 1998 showed a marked increase in delayed hypersensitivity, which is indicative of higher sensitization in persons inoculated with Mycobacterium tuberculosis. This appears to be associated with the higher frequency and spread of exogenous reinfections and with the increased virulence of the causative agent.     

Densitometric analysis of crystalline lens nucleus in the choice of strategy of surgical treatment of cataracts

Computer analysis of TV images of the eye was used for quantitative evaluation of optic density of the lens nucleus in patients with cataracts in need of surgical treatment. Indications to cataract phacoemulsification were determined using classification of the degree of the lens nucleus maturity. This classification is based on the maximal values of optic density of the anterior third of the nucleus, obtained by the lens densitometry, coefficient of light absorption by the lens nucleus, and tentative subjective classification of the lens nucleus maturity by a color scale. In initial cataract (first degree) the mean maximal optic density of the anterior third of the nucleus is 55.8 +/- 5.7 arb. units and coefficient of the lens nucleus light absorption is 0.93, in nuclear brown cataract (fourth degree) these values are 158.7 +/- 24.4 arb units and 1.81, respectively. Cataract with brown enlarged nucleus involving the cortical layers of the lens and high optic density of these layers, with lens nucleus light absorption coefficient more than 2.5 is a contraindication to phacoemulsification.     

Chemobiokinetics of sarcolysin and its peptides with glutaminic acid

A 14C study of chemobiokinetics of sarcolysin and its peptides of glutaminic acid, dosage and routes of administration was conducted in intact rats and those bearing Walker's carcinoma. Similar in shape for peptides, kinetic curves differed from those found for sarcolysin. The rates of absorption and excretion of sarcolysin peptides in intraperitoneal and, particularly, oral administration were lower than those of sarcolysin. Tumor appeared to play a role in a higher rate of peptide excretion. While sarcolysin and its peptides distribution in organs and tissues was generally identical, time of peak radioactive concentration build-up was different. Time needed for accumulation and excretion of peptides from tumor was much longer than from other organs or tissues. Sarcolysin went chiefly to urine while peptides--to faeces.