Preformed stiffeners used to fabricate structural components for pressurized tanks

Process of fabricating stiffened section components of pressurized tanks for aerospace use was developed. A potential use of the fabrication process is the production of gore and quarter-panel sections of hydrogen and oxygen tanks for space vehicle boosters

USSR Space Life Sciences Digest

Research in exobiology, life sciences technology, space biology, and space medicine and physiology, primarily using data gathered on the Salyut 6 orbital space station, is reported. Methods for predicting, diagnosing, and preventing the effects of weightlessness are discussed. Psychological factors are discussed. The effects of space flight on plants and animals are reported. Bioinstrumentation advances are noted

Macroscale and Nanoscale Photoelectrochemical Behavior of p-Type Si(111) Covered by a Single Layer of Graphene or Hexagonal Boron Nitride

Two-dimensional (2D) materials may enable a general approach to the introduction of a dipole at a semiconductor surface as well as control over other properties of the double layer at a semiconductor/liquid interface. Vastly different properties can be found in the 2D materials currently studied due in part to the range of the distribution of density-of-states. In this work, the open-circuit voltage (V_(oc)) of p-Si–H, p-Si/Gr (graphene), and p-Si/h-BN (hexagonal boron nitride) in contact with a series of one-electron outer-sphere redox couples was investigated by macroscale measurements as well as by scanning electrochemical cell microscopy (SECCM). The band gaps of Gr and h-BN (0–5.97 eV) encompass the wide range of band gaps for 2D materials, so these interfaces (p-Si/Gr and p-Si/h-BN) serve as useful references to understand the behavior of 2D materials more generally. The value of V_(oc) shifted with respect to the effective potential of the contacting solution, with slopes (ΔV_(oc)/ΔE_(Eff)) of −0.27 and −0.38 for p-Si/Gr and p-Si/h-BN, respectively, indicating that band bending at the p-Si/h-BN and p-Si/Gr interfaces responds at least partially to changes in the electrochemical potential of the contacting liquid electrolyte. Additionally, SECCM is shown to be an effective method to interrogate the nanoscale photoelectrochemical behavior of an interface, showing little spatial variance over scales exceeding the grain size of the CVD-grown 2D materials in this work. The measurements demonstrated that the polycrystalline nature of the 2D materials had little effect on the results and confirmed that the macroscale measurements reflected the junction behavior at the nanoscale

Enzymatic functionalization of carbon-hydrogen bonds

The development of new catalytic methods to functionalize carbon–hydrogen (C–H) bonds continues to progress at a rapid pace due to the significant economic and environmental benefits of these transformations over traditional synthetic methods. In nature, enzymes catalyze regio- and stereoselective C–H bond functionalization using transformations ranging from hydroxylation to hydroalkylation under ambient reaction conditions. The efficiency of these enzymes relative to analogous chemical processes has led to their increased use as biocatalysts in preparative and industrial applications. Furthermore, unlike small molecule catalysts, enzymes can be systematically optimized via directed evolution for a particular application and can be expressed in vivo to augment the biosynthetic capability of living organisms. While a variety of technical challenges must still be overcome for practical application of many enzymes for C–H bond functionalization, continued research on natural enzymes and on novel artificial metalloenzymes will lead to improved synthetic processes for efficient synthesis of complex molecules. In this critical review, we discuss the most prevalent mechanistic strategies used by enzymes to functionalize non-acidic C–H bonds, the application and evolution of these enzymes for chemical synthesis, and a number of potential biosynthetic capabilities uniquely enabled by these powerful catalysts (110 references)

USSR Space Life Sciences Digest, volume 2, no. 3

Soviet scientists are making significant contributions to the field of space medicine and biology through their active manned space program, frequent biosatellites, and extensive ground-based research. An overview of the developments and direction of the USSR Space Life Sciences Program is provided

Multifunctional transducer

Several parameters of a small region of a muscle tissue or other object, can be simultaneously measured using with minimal traumatizing or damage of the object, a trifunctional transducer which can determine the force applied by a muscle fiber, the displacement of the fiber, and the change in thickness of the fiber. The transducer has three legs with inner ends joined together and outer ends formed to piece the tissue and remain within it. Two of the legs are relatively stiff, to measure force applied by the tissue, and a third leg is relatively flexible to measure displacement of the tissue relative to one or both stiff legs, and with the three legs lying in a common plane so that the force and displacement measurements all relate to the same direction of muscle movements. A flexible loop is attached to one of the stiff legs to measure changes in muscle thickness, with the upper end of the loop fixed to the leg and the lower end of the loop bearing against the surface of the tissue and being free to slide on the leg

Fiscal sustainability in a new Keynesian model - additional appendix

Additional appendix relating to the article 'Fiscal sustainability in a new Keynesian model', forthcoming in the Journal of Money, Credit and Banking

Public views on the donation and use of human biological samples in biomedical research: a mixed methods study

Objective A mixed methods study exploring the UK general public's willingness to donate human biosamples (HBSs) for biomedical research.<p></p> Setting Cross-sectional focus groups followed by an online survey.<p></p> Participants Twelve focus groups (81 participants) selectively sampled to reflect a range of demographic groups; 1110 survey responders recruited through a stratified sampling method with quotas set on sex, age, geographical location, socioeconomic group and ethnicity.<p></p> Main outcome measures (1) Identify participants’ willingness to donate HBSs for biomedical research, (2) explore acceptability towards donating different types of HBSs in various settings and (3) explore preferences regarding use and access to HBSs.<p></p> Results 87% of survey participants thought donation of HBSs was important and 75% wanted to be asked to donate in general. Responders who self-reported having some or good knowledge of the medical research process were significantly more likely to want to donate (p<0.001). Reasons why focus group participants saw donation as important included: it was a good way of reciprocating for the medical treatment received; it was an important way of developing drugs and treatments; residual tissue would otherwise go to waste and they or their family members might benefit. The most controversial types of HBSs to donate included: brain post mortem (29% would donate), eyes post mortem (35%), embryos (44%), spare eggs (48%) and sperm (58%). Regarding the use of samples, there were concerns over animal research (34%), research conducted outside the UK (35%), and research conducted by pharmaceutical companies (56%), although education and discussion were found to alleviate such concerns.<p></p> Conclusions There is a high level of public support and willingness to donate HBSs for biomedical research. Underlying concerns exist regarding the use of certain types of HBSs and conditions under which they are used. Improved education and more controlled forms of consent for sensitive samples may mitigate such concerns.<p></p&gt

Normalizing connections and the energy-momentum method

The block diagonalization method for determining the stability of relative equilibria is discussed from the point of view of connections. We construct connections whose horizontal and vertical decompositions simultaneosly put the second variation of the augmented Hamiltonian and the symplectic structure into normal form. The cotangent bundle reduction theorem provides the setting in which the results are obtained