Analytical Investigation of the Reentry Behavior of the ''flying Wind Tunnel'' Test Vehicle, with Some Effects of Threshold and Torque Level of a Roll-rate Control System

Analytical investigation of reentry behavior of flying wind tunnel test vehicle with some effects of threshold and torque level of roll-rate control syste

The oxidative stress theory of disease: levels of evidence and epistemological aspects

The theory stating that oxidative stress (OS) is at the root of several diseases is extremely popular. However, so far, no antioxidant is recommended or offered by healthcare systems neither approved as therapy by regulatory agencies that base their decisions on evidence-based medicine (EBM). This is simply because, so far, despite many preclinical and clinical studies indicating a beneficial effect of antioxidants in many disease conditions, randomised clinical trials have failed to provide the evidence of efficacy required for drug approval. In this review, we discuss the levels of evidence required to claim causality in preclinical research on OS, the weakness of the oversimplification associated with OS theory of disease and the importance of the narrative in its popularity. Finally, from a more translational perspective, we discuss the reasons why antioxidants acting by scavenging reactive oxygen species (ROS) might not only prevent their detrimental effects but also interfere with essential signalling roles. We propose that ROS have a complex metabolism and are generated by different enzymes at diverse sites and with different timing. Aggregating this plurality of systems in a single theory of disease may not be the best way to develop new drugs, and future research may need to focus on specific oxygen-toxifying pathways rather than on non-specific ROS scavengers. Finally, similarly to what is nowadays required for clinical trials, we recommend making unpublished data available in repositories (open data), as this will allow big data approaches or meta-analyses without the blinders of the publication bias

Investigation of the Influence of Fuselage and Tail Surfaces on Low-speed Static Stability and Rolling Characteristics of a Swept-wing Model

Results are presented of a wind-tunnel investigation to determine influence of the fuselage and tail on static stability and rotary derivatives in roll of a model having 45 degrees sweptback wing and tail surfaces. The wing alone and the model without the horizontal tail showed marginal longitudinal stability near maximum lift. The longitudinal stability of the complete model was satisfactory. The vertical tail produced larger increments of rate of change of lateral-force and yawing-moment coefficients with wing-tip helix angle than the fuselage or the horizontal tail

Pharmacology and clinical drug candidates in redox medicine

SIGNIFICANCE Oxidative stress is suggested to be a disease mechanism common to a wide range of disorders affecting human health. However, so far, the pharmacotherapeutic exploitation of this, for example, based on chemical scavenging of pro-oxidant molecules, has been unsuccessful. Recent Advances: An alternative emerging approach is to target the enzymatic sources of disease-relevant oxidative stress. Several such enzymes and isoforms have been identified and linked to different pathologies. For some targets, the respective pharmacology is quite advanced, that is, up to late-stage clinical development or even on the market; for others, drugs are already in clinical use, although not for indications based on oxidative stress, and repurposing seems to be a viable option. CRITICAL ISSUES For all other targets, reliable preclinical validation and drug ability are key factors for any translation into the clinic. In this study, specific pharmacological agents with optimal pharmacokinetic profiles are still lacking. Moreover, these enzymes also serve largely unknown physiological functions and their inhibition may lead to unwanted side effects. FUTURE DIRECTIONS The current promising data based on new targets, drugs, and drug repurposing are mainly a result of academic efforts. With the availability of optimized compounds and coordinated efforts from academia and industry scientists, unambiguous validation and translation into proof-of-principle studies seem achievable in the very near future, possibly leading towards a new era of redox medicine

NACA Research Memorandums

Report presenting a wind-tunnel investigation at low speed to determine the effects of sideslip on the static longitudinal trim characteristics of three fighter-type airplane models. The three models consisted of a 45 degree swept-wing model with a horizontal tail geometrically similar to the wing and mounted slightly below the wing, a clipped-delta-wing model with a horizontal tail mounted in a moderately high position, and a 60 degree delta-wing with no horizontal tail. Results regarding static longitudinal stability, variation of pitching-moment coefficient with sideslip, effect of modifications to Model B on static longitudinal stability and variation of pitching-moment coefficient with sideslip, and static lateral stability are presented