Beyond Earth’s Gravity: Navigating Legal Hurdles in Space-Based Drug Research and Development

An experimental and numerical investigation on the hot surface ignition of premixed gases under microgravity conditions

Organ printing, a novel approach in tissue engineering, applies computer-driven deposition of cells, growth factors, biomaterials layer-by-layer to create complex 3D tissue or organ constructs. This emerging technology shows great promise in regenerative medicine, because it may help to address current crisis of tissue and organ shortage for transplantation. Organ printing is developing fast, and there are exciting new possibilities in this area. Successful cell and organ printing requires many key elements. Among these, the choice of appropriate cells for printing is vital. This chapter surveys available cell sources for cell and organ printing application and discusses factors that affect cell choice. Special emphasis is put on several important factors, including the proposed printing system and bioprinters, the assembling method, and the target tissues or organs, which need to be considered to select proper cell sources and cell types. In this chapter, characterizations of the selected cells to justify and/or refine the cell selection will also be discussed. Finally, future prospects in this field will be envisioned.

Alkali cyanides in the iron blast-furnace

Bioprinting is the precise automated robotic layer-by-layer additive fabrication of biomaterials. The future of bioprinting technology depends on a number of essential elements, such as the development of innovative bioprinting apparatus and bioprinting methods. The application of innovative bioprinting technologies will have a tremendous impact on the advancement of tissue engineering and regenerative medicine. In this review we survey and report on a range of patents and some journal articles that describe the latest advancements in bioprinting as they relate to tissue engineering. Our analysis of the state of the art revealed that novel patents for bioprinting methods can be categorized into three areas; cell free scaffolds, cellularized scaffolds, and cell and tissue bioprinting. Our analysis also revealed a number of trends including the push to design the first clinical bioprinting apparatus and in vivo bioprinting robots, as well as methods to fabricate vascularized tissue and the first clinically approved cell free implants. Keywords: Bioprinting, biofabrication, biomaterial, bioink, biopolymer, hydrogel, cell printing, tissue printing, organ printing, scaffold, tissue engineering, bioreactor, cell assay, tissue device, spheroid

The International Conference on Bioprinting and Biofabrication in Bordeaux (3B'09) demonstrated that the field of bioprinting and biofabrication continues to evolve. The increasing number and broadening geography of participants, the emergence of new exciting bioprinting technologies, and the attraction of young investigators indicates the strong growth potential of this emerging field. Bioprinting can be defined as the use of computer-aided transfer processes for patterning and assembling living and non-living materials with a prescribed 2D or 3D organization in order to produce bio-engineered structures serving in regenerative medicine, pharmacokinetic and basic cell biology studies. The use of bioprinting technology for biofabrication of in vitro assay has been shown to be a realistic short-term application. At the same time, the principal feasibility of bioprinting vascularized human organs as well as in vivo bioprinting has been demonstrated. The bioprinting of complex 3D human tissues and constructs in vitro and especially in vivo are exciting, but long-term, applications. It was decided that the 5th International Conference on Bioprinting and Biofabrication would be held in Philadelphia, USA in October 2010. The specially appointed 'Eploratory Committee' will consider the possibility of turning the growing bioprinting community into a more organized entity by creating a new bioprinting and biofabrication society. The new journal Biofabrication was also presented at 3B'09. This is an important milestone per se which provides additional objective evidence that the bioprinting and biofabrication field is consolidating and maturing. Thus, it is safe to state that bioprinting technology is coming of age.

Cell or organ printing is any technology that enables a user to deposit precise patterns of living cells or cell aggregates throughout three dimensional (3D) tissue engineering scaffolds. Traditional tissue engineering approaches utilize random cell seeding (flooding) of porous scaffolds to promote cell attachment. While this approach does allow cells to diffuse and attach throughout macroscopic scaffolds, there are both biological and material limitations of this approach, namely the inability to mimic the cellular/molecular heterogeneity and structure (vascularization, sinuses, etc.) found in natural tissue. Cell printing offers the unique possibility of creating tissue scaffolds with pre-built cellular/molecular heterogeneity and structure through layer-by-layer fabrication. The aim of this review is to illustrate the different approaches to building tissue scaffolds via cell printing, describe the specific cell printers in the peer-reviewed and patent literature with their demonstrated capabilities, and then discuss the future of these technologies with respect to important biomedical applications such as tissue engineering, organ replacement and tissue microdissection. Keywords: Cell printing, organ printing, ink jet, laser induced forward transfer (LIFT), biological laser printing (BioLP), solid freeform fabrication, human architectural tool (HAT), laser guided direct write (LG DW)

Two-phase flows of gas and liquid are increasingly paid much attention to space application due to excellent properties of heat and mass transfer, so it is very meaningful to develop studies on them in microgravity. In this paper, gas-phase distribution and turbulence characteristics of bubbly flow in normal gravity and microgravity were investigated in detail by using Euler–Lagrange two-way model. The liquid-phase velocity field was solved by using direct numerical simulations (DNS) in Euler frame of reference, and the bubble motion was tracked by using Newtonian motion equations that took into account interphase interaction forces including drag force, shear lift force, wall lift force, virtual mass force and inertia force, etc. in Lagrange frame of reference. The coupling between gas–liquid phases was made with regarding interphase forces as a momentum source term in the momentum equation of the liquid phase. Under the normal gravity condition, a great number of bubbles accumulate near the walls under the influence of the shear lift force, and addition of bubbles reduces turbulence of the liquid phase. Different from the normal gravity condition, in microgravity, an overwhelming majority of bubbles migrate towards the centre of the channel driven by the pressure gradient force, and bubbles have little effect on the turbulence of the liquid phase.

Limiting oxygen concentration for extinction of upward spreading flames over inclined thin polyethylene-insulated NiCr electrical wires with opposed-flow under normal- and micro-gravity

This study explores a novel hypothesis. According to Taheri, various T-Consciousness Fields (TCFs) exist, each with distinct functions, and are considered subsets of the Cosmic Consciousness Network. Although these fields lack any physical entity, their effects can be detected through laboratory experiments. It is hypothesized that when a subject is exposed to TCFs, the information transmitted from these fields can alter the properties or behavior of the treated samples compared to untreated controls. In the present experiment, the Faradarmani Consciousness Field, one type of TCF, was applied to investigate its effect on the cell cycle progression of the lymphoma Raji cell line under both simulated microgravity and normal Earth gravity conditions. There were four experimental groups, and the experiment duration was 48 hours. Samples not exposed to the Faradarmani Consciousness Field were considered the control group. Based on flow cytometry analysis, apoptosis was observed in cells exposed to microgravity (MG), with the sub-G1 phase increasing to approximately 42% (p-value< 0.05), whereas Faradarmani-treated samples remained almost unchanged under MG stress Similarly, Faradarmani-treated samples exhibited similar percentages of G1 and S phases under microgravity conditions compared to Earth gravity, while a significant decrease was observed in samples without the field effect (p-value < 0.05). However, under normal gravity conditions, the effect of FCF was not significant compared to the control. These observations suggest that the Faradarmani Consciousness Field influences cell cycle progression differently depending on environmental conditions. Under microgravity (MG) stress, the information transmitted from this T-Consciousness Field appears to have an alleviating effect, whereas under normal Earth gravity, it did not produce a significant change.

Oscillatory thermocapillary convection in a liquid bridge: Part 1—1 g Experiments

Numerical simulation of subcooled flow boiling under conjugate heat transfer and microgravity condition in a vertical mini channel

A transient short-hot-wire technique is proposed and used to measure the thermal conductivity and thermal diffusivity of liquids simultaneously. The method is based on the numerical evaluation of unsteady heat conduction from a wire with the same length diameter ratio and boundary conditions as those in the experiments. To confirm the applicability and accuracy of this method. Measurements were made for five sample liquids with known thermophysical properties and were performed under both normal gravity and microgravity conditions. The results reveal that the present method determines both the thermal conductivity and the diffusivity within 2 and 5%. respectively. The microgravity experiments clearly indicate that even under normal gravity conditions, natural-convection effects are negligible for at least l s after the start of heating. This method would be particularly suitable for a valuable and expensive liquid, and has a potential for application to electrically conducting and or corrosive liquids when the probe is effectively coated with an insulating and anticorrosive material.

In view of the great importance of two geometrical parameters such as void fraction and interfacial area concentration to the accurate two-phase flow analysis at microgravity conditions, axial developments of flow parameters such as void fraction, interfacial area concentration, bubble Sauter mean diameter, and bubble number density were measured in bubbly flow at microgravity and low liquid Reynolds number conditions where the gravity effect on the flow parameters were pronounced. A total of seven data sets were acquired in the flow range of the void fraction from 1.01% to 3.36% and the liquid Reynolds number from 1,400 to 4,750. The measurements were also performed in the similar flow range at normal gravity conditions. The transport mechanisms of the flow parameters are discussed in detail based on the data measured at normal and microgravity conditions, and the drift-flux model developed at microgravity conditions are compared with the measured data.

Marangoni convection significantly affects the solidification structure as it controls the bubble behavior and mass transfer in the melt. Sn-3.5Ag/Sn-17Bi-0.5Cu (wt pct) alloy with different surface tension gradients was fabricated and solidified on a Cu ring substrate under space microgravity condition (SJ-10 satellite) to study the Marangoni convection formation mechanism. The pore and element distributions in the solidified alloy and surface tension gradient in the melt were analyzed. The differences between the microstructures of alloys solidified under microgravity and normal gravity conditions were also investigated. The surface tension gradient induced by Bi concentration difference resulted in the formation of Marangoni convection from the right to left of the melt under the microgravity condition. In the left (Bi-scarce) part of the melt, Marangoni convection induced by the Cu concentration difference flowed from outside to inside. Driven by bubble-agitation convection, Cu mainly migrated from the substrate to the right part of the melt. Therefore, dendrite-like CuxSny was distributed along a gradient. Under the normal gravity condition, significant gravity-induced convection resulted in an even distribution of Bi and Cu, which decreased the contact angle and reduced the surface tension, thus promoting nucleation of the alloy. Therefore, fine dendrite-like CuxSny with larger number density were uniformly distributed in the melt.

The effect of gravity on the combustion synthesis characteristics and the resultant microstructures of the synthesized metal matrix composites (MMCs) were studied for the HfB2/Al and Ni3Ti/TiB2 reaction systems conducted under both normal (1 g) and low gravity conditions. Under normal gravity conditions, the pellets were ignited at three orientations to the gravity vector. The low gravity combustion synthesis reactions were conducted on a DC-9 aircraft at NASA Lewis Research Center (NASA-LeRC). It was found that under normal gravity conditions, both the combustion temperature and wave velocity were highest when the pellets were ignited from the bottom. Both the combustion temperature and wave velocity were lower when conducting the reactions under low gravity than under normal gravity conditions. It is believed that the convective flow of argon gas was responsible for this phenomenon. Gravity-induced, density-driven fluid flow (sedimentation) of the heavier phases in the MMCs was also observed for both re...