Correction of ADA-SCID by stem cell gene therapy combined with nonmyeloablative conditioning

Hematopoietic stem cell (HSC) gene therapy for adenosine deaminase (ADA)-deficient severe combined immunodeficiency (SCID) has shown limited clinical efficacy because of the small proportion of engrafted genetically corrected HSCs. We describe an improved protocol for gene transfer into HSCs associated with nonmyeloablative conditioning. This protocol was used in two patients for whom enzyme replacement therapy was not available, which allowed the effect of gene therapy alone to be evaluated. Sustained engraftment of engineered HSCs with differentiation into multiple lineages resulted in increased lymphocyte counts, improved immune functions (including antigen-specific responses), and lower toxic metabolites. Both patients are currently at home and clinically well, with normal growth and development. These results indicate the safety and efficacy of HSC gene therapy combined with nonmyeloablative conditioning for the treatment of SCID.     

The environmental movement and labor in global capitalism: Lessons from the case of the Headwaters Forest

Employing the case of theredwood Headwaters forest in rural NorthernCalifornia, this paper investigates the extentto which an anti-corporate progressive alliancebetween labor and the environmental movement ispossible in contemporary global capitalism.Progressive alliances between labor and theenvironmental movement have been historicallydifficult. This has been particularly the casein the timber industry, where companies havebeen able to mobilize workers againstenvironmentalists' designs. The caseillustrates the events that led to the purchaseof the Headwaters Forest by the state ofCalifornia and the Federal Government fromPacific Lumber. This is a subsidiary of Maxxam,a corporation with interests in a variety ofeconomic sectors. The objective was to haltMaxxam's rampant deforestation of old growthredwood. Though conflict between labor andenvironmentalists existed, the casedemonstrates that the labor and theenvironmental movement were united againstMaxxam. They, however, were not completelysuccessful in their struggle as Maxxam greatlybenefited from the state-sponsored landpurchase. Maxxam gained economically, was ableto shape the ideological framework throughwhich the purchasing agreement was achieved,and extended its hegemony over the state. Thisoutcome cast doubts on the possibility thatcurrent forms of environmental protection couldtranscend commodified and reductionistpostures. Simultaneously, the existence of acommon anti-corporate consciousness among largesegments of labor and the environmentalmovement makes the environment a contestedterrain and allows for some optimism about thefuture of the struggle for ecologically soundsocial arrangements.     

Radar soundings of the subsurface of Mars

The martian subsurface has been probed to kilometer depths by the Mars Advanced Radar for Subsurface and Ionospheric Sounding instrument aboard the Mars Express orbiter. Signals penetrate the polar layered deposits, probably imaging the base of the deposits. Data from the northern lowlands of Chryse Planitia have revealed a shallowly buried quasi-circular structure about 250 kilometers in diameter that is interpreted to be an impact basin. In addition, a planar reflector associated with the basin structure may indicate the presence of a low-loss deposit that is more than 1 kilometer thick.     

Structural and technical development in agriculture: An international overview

This study investigates the socio-historical relationships existing between the development of the agricultural structure and the process of technical development. Adopting a political economy posture, it is argued that the development of technical procedures in agriculture has been aimed historically at the maximization of production and productivity. This phenomenon has been generated by the social hegemony of groups interested in the enhancement of accumulation of capital and has been translated into an emphasis on large productive units, which discriminates against small and medium farms. This pattern of development has been legitimized through a social consensus which involves an emphasis on small family producers. This contradiction is embodied in the generation of a dualistic agricultural structure characterized by the prosperity of large farms, the persistence of small farms and the crisis of medium farms and in patterns of overproduction and unavailability of food for the poor segments of society.     

The mass disruption of Oort cloud comets

We have calculated the number of dormant, nearly isotropic Oort cloud comets in the solar system by (i) combining orbital distribution models with statistical models of dormant comet discoveries by well-defined surveys and (ii) comparing the model results to observations of a population of dormant comets. Dynamical models that assume that comets are not destroyed predict that we should have discovered approximately 100 times more dormant nearly isotropic comets than are actually seen. Thus, as comets evolve inward from the Oort cloud, the majority of them must physically disrupt.     

Laser-induced selectivity for dimerization versus polymerization of butadiene under pressure

The pressure-induced chemical reaction of liquid butadiene was studied by Fourier transform infrared spectroscopy in a diamond anvil cell. Dimerization was found to occur above 0.7 gigapascal, giving vinylcyclohexene according to a cyclo-addiction reaction and only a trace amount of polybutadiene forms. By irradiating the high-pressure sample with a few milliwatts of the 488-nanometer argon+ laser line, the dimerization was completely inhibited, and the rapid formation of pure trans-polybutadiene was observed. The use of different excitation wavelength allows us to emphasize the selectivity of the process and to identify the active role of the 2(1)Ag state in this pressure- and laser-induced chemical reaction.     

Magma ascent and the pressurization of Mount Etna's volcanic system

After a period of deflation during the 1991-1993 flank eruption, Mount Etna underwent a rapid inflation. Seismicity and ground deformation show that since 1994, a huge volume of magma intruded beneath the volcano, producing from 1998 onward a series of eruptions at the summit and on the flank of the volcano. The last of these, started on 27 October 2002, is still in progress and can be considered one of the most explosive eruptions of the volcano in recent times. Here we show how geodetic data and seismic deformation, between 1994 and 2001, indicate a radial compression around an axial intrusion, consistent with a repressurization of Mount Etna's plumbing system at a depth of 6 to 15 kilometers, which triggered most of the seismicity and provoked the dilatation of the volcano and the recent explosive eruptive activity.