Fusion Energy Output Greater than the Kinetic Energy of an Imploding Shell at the National Ignition Facility

A series of cryogenic, layered deuterium-tritium (DT) implosions have produced, for the first time, fusion energy output twice the peak kinetic energy of the imploding shell. These experiments at the National Ignition Facility utilized high density carbon ablators with a three-shock laser pulse (1.5 MJ in 7.5 ns) to irradiate low gas-filled (0.3  mg/cc of helium) bare depleted uranium hohlraums, resulting in a peak hohlraum radiative temperature ∼290  eV. The imploding shell, composed of the nonablated high density carbon and the DT cryogenic layer, is, thus, driven to velocity on the order of 380  km/s resulting in a peak kinetic energy of ∼21  kJ, which once stagnated produced a total DT neutron yield of 1.9×10¹⁶ (shot N170827) corresponding to an output fusion energy of 54 kJ. Time dependent low mode asymmetries that limited further progress of implosions have now been controlled, leading to an increased compression of the hot spot. It resulted in hot spot areal density (ρr∼0.3  g/cm²) and stagnation pressure (∼360  Gbar) never before achieved in a laboratory experiment

mTORC1 Inhibition via Rapamycin Promotes Triacylglycerol Lipolysis and Release of Free Fatty Acids in 3T3â L1 Adipocytes

Signaling by mTOR complex 1 (mTORC1) promotes anabolic cellular processes in response to growth factors, nutrients, and hormonal cues. Numerous clinical trials employing the mTORC1 inhibitor rapamycin (aka sirolimus) to immunoâ suppress patients following organ transplantation have documented the development of hypertriglyceridemia and elevated serum free fatty acids (FFA). We therefore investigated the cellular role of mTORC1 in control of triacylglycerol (TAG) metabolism using cultured murine 3T3â L1 adipocytes. We found that treatment of adipocytes with rapamycin reduced insulinâ stimulated TAG storage ~50%. To determine whether rapamycin reduces TAG storage by upregulating lipolytic rate, we treated adipocytes in the absence and presence of rapamycin and isoproterenol, a β2â adrenergic agonist that activates the cAMP/protein kinase A (PKA) pathway to promote lipolysis. We found that rapamycin augmented isoproterenolâ induced lipolysis without altering cAMP levels. Rapamycin enhanced the isoproterenolâ stimulated phosphorylation of hormone sensitive lipase (HSL) on Serâ 563 (a PKA site), but had no effect on the phosphorylation of HSL S565 (an AMPK site). Additionally, rapamycin did not affect the isoproterenolâ mediated phosphorylation of perilipin, a protein that coats the lipid droplet to initiate lipolysis upon phosphorylation by PKA. These data demonstrate that inhibition of mTORC1 signaling synergizes with the βâ adrenergicâ cAMP/PKA pathway to augment phosphorylation of HSL to promote hormoneâ induced lipolysis. Moreover, they reveal a novel metabolic function for mTORC1; mTORC1 signaling suppresses lipolysis, thus augmenting TAG storage.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141428/1/lipd1089.pd

Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

Caracterización de las tendencias en los modelos para estudiar problemas de equipamiento y adquisición de tecnología

Estudio descriptivo de las tendencias en los modelos para evaluación de tecnologías de equipo. En él se caracterizan los modelos en el estado del arte y los de la práctica generalizada para evaluar tecnologías, también se exponen las debilidades de los diversos tipos de modelos y se destacan las opiniones de los expertos sobre los contenidos de teorías más efectivas para estudiar este tipo de problemas. En este trabajo se considera que el equipamiento es un caso específico de transferencia de tecnología, que es un problema muy amplio que puede incluir al reemplazo de equipos, la adopción y asimilación de tecnologías y algunos proyectos de innovación y desarrollo de tecnología. Siendo todos ellos problemas de planeación de la tecnología de la empresa y por tanto, complejos, extensos, que aún no están estructurados de una forma generalmente aceptada, definitiva, efectiva y cómo la tecnología es la principal fuente de ventaja competitiva, por ello es necesario determinar el estado del arte y las prácticas industriales con las que se aborda este tipo de problemas