The reaction specificities of the pea and a cyanobacterial thylakoid processing peptidase are similar but not identical

AbstractThe thylakoid processing peptidase from the cyanobacterium Phormidium laminosum has been extracted from thylakoid membranes by solubilization with Triton X-100. Its reaction specificity has been compared with the analogous pea peptidase by processing in vitro of radiolabelled wheat and P. laminosum thylakoid lumenal precursor polypeptides. The cyanobacterial polypeptide is processed to the mature size through an intermediate by the P. laminosum peptidase, but to a polypeptide that has a slightly greater apparent molecular weight than the intermediate by the pea peptidase. Both peptidases correctly process the wheat polypeptide. This suggests that the reaction specificities of the two peptidases are similar, but not identical

Global Livestock Production Systems

Informed livestock sector policy development and priority setting is heavily dependent on a good understanding of livestock production systems. In a collaborative effort between the Food and Agriculture Organization and the International Livestock Research Institute, stock has been taken of where we have come from in agricultural systems classification and mapping; the current state of the art; and the directions in which research and data collection efforts need to take in the future. The book also addresses issues relating to the intensity and scale of production, moving from what is done to how it is done. The intensification of production is an area of particular importance, for it is in the intensive systems that changes are occurring most rapidly and where most information is needed on the implications that intensification of production may have for livelihoods, poverty alleviation, animal diseases, public health and environmental outcomes. A series of case studies is provided, linking livestock production systems to rural livelihoods and poverty and examples of the application of livestock production system maps are drawn from livestock production, now and in the future; livestock's impact on the global environment; animal and public health; and livestock and livelihoods. This book provides a formal reference to Version 5 of the global livestock production systems map, and to revised estimates of the numbers of rural poor livestock keepers, by country and livestock production system. These maps and data are freely available for download via FAO's web pages: www.fao.org/AG/againfo/resources/en/glw/home.html. It is hoped that this publication will stimulate further work in this field and encourage the use of livestock production systems information and maps in research and analysis

Magnetic trapping of metastable 3P2^3P_2 atomic strontium

We report the magnetic trapping of metastable $^3P_2$ atomic strontium. Atoms are cooled in a magneto-optical trap (MOT) operating on the dipole allowed $^1S_0-^1P_1$ transition at 461 nm. Decay via $^1P_1\to {^1D_2}\to {^3P_2}$ continuously loads a magnetic trap formed by the quadrupole magnetic field of the MOT. Over $10^8$ atoms at a density of $8 \times 10^9$ cm$^{-3}$ and temperature of 1 mK are trapped. The atom temperature is significantly lower than what would be expected from the kinetic and potential energy of atoms as they are transferred from the MOT. This suggests that thermalization and evaporative cooling are occurring in the magnetic trap.Comment: This paper has been accepted by PR

Photoionization of ultracold and Bose-Einstein condensed Rb atoms

Photoionization of a cold atomic sample offers intriguing possibilities to observe collective effects at extremely low temperatures. Irradiation of a rubidium condensate and of cold rubidium atoms within a magneto-optical trap with laser pulses ionizing through 1-photon and 2-photon absorption processes has been performed. Losses and modifications in the density profile of the remaining trapped cold cloud or the remaining condensate sample have been examined as function of the ionizing laser parameters. Ionization cross-sections were measured for atoms in a MOT, while in magnetic traps losses larger than those expected for ionization process were measured.Comment: 9 pages, 7 figure

The African warlord revisited

To date, warlordism in Africa has been viewed solely negatively. This has come about, in part, because of the analytical lenses that have been used. Typically, warlordism has been examined at the state level; and behavioural traits, rather than definitionally necessary components, have been the focus. In effect, ‘warlord’ has been confused with other violent actors. I suggest here a reconceptualisation ‘from below’, which takes into account variation in types of warlordism, and which allows for both positive and negative effects of warlordism on society and the state

Chaos in a double driven dissipative nonlinear oscillator

We propose an anharmonic oscillator driven by two periodic forces of different frequencies as a new time-dependent model for investigating quantum dissipative chaos. Our analysis is done in the frame of statistical ensemble of quantum trajectories in quantum state diffusion approach. Quantum dynamical manifestation of chaotic behavior, including the emergence of chaos, properties of strange attractors, and quantum entanglement are studied by numerical simulation of ensemble averaged Wigner function and von Neumann entropy.Comment: 9 pages, 18 figure

Hawking Radiation of Black Holes in Infrared Modified Ho\v{r}ava-Lifshitz Gravity

We study the Hawking radiation of the spherically symmetric, asymptotically flat black holes in the infrared modified Horava-Lifshitz gravity by applying the methods of covariant anomaly cancellation and effective action, as well as the approach of Damour-Ruffini-Sannan's. These black holes behave as the usual Schwarzschild ones of the general relativity when the radial distance is very large. We also extend the method of covariant anomaly cancellation to derive the Hawking temperature of the spherically symmetric, asymptotically AdS black holes that represent the analogues of the Schwarzschild AdS ones.Comment: no figures, 16 pages,accepted by EPJ

S. P. Hopper: First In-Situ Exploration of Lunar Polar Terrain

Intuitive Machines Mission - 2 (IM2) Nova-C lander is slated to land on the Spudis crater side of the Shackleton – de Gerlache connecting ridge (89.5°S, 222.0°E) in late 2022 or early 2023. The Nova-C carries three core payload elements: the NASA-funded Polar Resources Ice-Mining Experiment-1 (PRIME-1), a 4G/LTE communications network developed by Nokia of America Corporation on the Nova-C lander, the Micro-Nova and a Mobile Autonomous Prospecting Platform (MAPP) rover developed by Lunar Outpost Inc., and Micro-Nova, a deployable hopper robot developed by Intuitive Machines. Here we summarize the capabilities of the Micro-Nova (named S.P. Hopper for this mission) and its goals and objectives

Thermal and photochemical control of nitro-nitrito linkage isomerism in single-crystals of [Ni(medpt)(NO₂)(η²-ONO)]

The known complex [Ni(medpt)(η1-NO2)(η2-ONO)] 1 (medpt = 3,3′-diamino-N-methyldipropylamine) crystallises in the monoclinic space group P21/m with 1.5 molecules in the asymmetric unit with two different η1-NO2 ligand environments in the crystal structure. At 298 K the molecule (A) sitting in a general crystallographic site displays a mixture of isomers, 78% of the η1-NO2 isomer and 22% of an endo-nitrito–(η1-ONO) form. The molecule (B) sitting on a crystallographic mirror plane adopts the η1-NO2 isomeric form exclusively. However, a variable temperature crystallographic study showed that the two isomers were in equilibrium and upon cooling to 150 K the η1-ONO isomer converted completely to the η1-NO2 isomer, so that both independent molecules in the asymmetric unit were 100% in the η1-NO2 form. A kinetic analysis of the equilibrium afforded values of ΔH = −9.6 (±0.4) kJ mol−1, ΔS = −21.5 (±1.8) J K−1 mol−1 and EA = −1.6 (±0.05) kJ mol−1. Photoirradiation of single crystals of 1 with 400 nm light, at 100 K, resulted in partial isomerisation of the η1-NO2 isomer to the metastable η1-ONO isomer, with 89% for molecule (A), and 32% for molecule (B). The crystallographic space group also reduced in symmetry to P21 with Z′ = 3. The metastable state existed up to a temperature of 150 K above which temperature it reverted to the ground state. An analysis of the crystal packing in the ground and metastable states suggests that hydrogen bonding is responsible for the difference in the conversion between molecules (A) and (B)