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The article addresses to the main characteristics of Chulbatkan gold deposit. The deposit is a steeply dipping of bed and lenticular ore bodies with dessimination-veinlet mineralization in the late Cretaceous plagiogranites (Lower Amur complex), controlled by the NE and the NW faults. The host rock mineralization exposed hydrothermal and metasomatic processes (beresitization, silicification and carbonation). The only useful component of the low-graded and non-refractory ore is gold; silver grade is low. Resource potential of the deposit estimated as 50 tons.

Although the Low Countries formed a political unity only for short periods they have been seen by other European nations as a region in its own right. What created some kind of unity, as experienced by the inhabitants? My concept started from the geographical conditions of a delta of three major rivers, in a generally flat area facilitating transport. This was a basic condition for urban growth. The core questions were therefore – what at different times in the various regions, led to that extraordinary level of urbanisation on a European scale? Why and how did the successive 'golden ages' come to an end, and what remained in the previous core areas? Why did some regions remain peripheral? How do the various aspects interrelate – geographical conditions, social and political institutional arrangements, economic developments, and how do cultural phenomena fit into these patterns? This response is part of the discussion forum 'Four Golden Ages' (Wim Blockmans).

Although the Low Countries formed a political unity only for short periods they have been seen by other European nations as a region in its own right. What created some kind of unity, as experienced by the inhabitants? My concept started from the geographical conditions of a delta of three major rivers, in a generally flat area facilitating transport. This was a basic condition for urban growth. The core questions were therefore – what at different times in the various regions, led to that extraordinary level of urbanisation on a European scale? Why and how did the successive 'golden ages' come to an end, and what remained in the previous core areas? Why did some regions remain peripheral? How do the various aspects interrelate – geographical conditions, social and political institutional arrangements, economic developments, and how do cultural phenomena fit into these patterns?

This open access book is about understanding the processes involved in the transformation of smallholder rice farming in the Lower Mekong Basin from a low-yielding subsistence activity to one producing the surpluses needed for national self-sufficiency and a high-value export industry. For centuries, farmers in the Basin have regarded rice as "white gold", reflecting its centrality to their food security and well-being. In the past four decades, rice has also become a commercial crop of great importance to Mekong farmers, augmenting but not replacing its role in securing their subsistence. This book is based on collaborative research to (a) compare the current situation and trajectories of rice farmers within and between different regions of the Lower Mekong, (b) explore the value chains linking rice farmers with new technologies and input and output markets within and across national borders, and (c) understand the changing role of government policies in facilitating the on-going evolution of commercial rice farming. An introductory section places the research in geographical and historical context. Four major sections deal in turn with studies of rice farming, value chains, and policies in Northeast Thailand, Central Laos, Southeastern Cambodia, and the Mekong Delta. The final section examines the implications for rice policy in the region as a whole.

1. The Evolution of Rice Farming in the Lower Mekong Basin -- 2. The Commercialisation of Rice Farming in Northeast Thailand -- 3. Divergent Pathways of Rice Farming in Ubon Ratchathani Province -- 4. Farmer Organizations in Ubon Ratchathani Province -- 5. From Subsistence to Commercial Rice Farming in Laos -- 6. Adapting the Green Revolution for Laos -- 7. Rainfed and Irrigated Rice Farming on the Savannakhet Plain -- 8. The Supply of Inputs to Rice Farmers in Savannakhet -- 9. Rice Marketing and Cross-Border Trade in Savannakhet -- 10. Economic Constraints to Intensification of Rainfed Lowland Rice in Laos -- 11. The Commercialisation of Rice Farming in Cambodia -- 12. The Production, Marketing, and Export of Rice in Takeo -- 13. The Role of Irrigation in Rice Farming in Takeo and Kampong Speu -- 14. The Supply of Fertiliser for Rice Farming in Takeo -- 15. The Use of Credit by Rice Farmers in Takeo -- 16. Contract Farming of High-Quality Rice in Kampong Speu -- 17. Trends in Rice-Based Farming Systems in the Mekong Delta -- 18. The Domestic Rice Value Chain in the Mekong Delta -- 19. Cross-Border Trade in Rice from Cambodia to Vietnam -- 20. Cross-Border Trade in Sticky Rice from Laos to Vietnam -- 21. Issues of Rice Policy in the Lower Mekong Basin.

Objective. Electrical stimulation of the peripheral nervous system (PNS) can treat various diseases and disorders, including the healing process after nerve injury. A major challenge when designing electrodes for PNS stimulation is the mechanical mismatch between the nerve and the device, which can lead to non-conformal contact, tissue damage and inefficient stimulation due to current leakage. Soft and stretchable cuff electrodes promise to tackle these challenges but often have limited performance and rely on unconventional materials. The aim of this study is to develop a high performance soft and stretchable cuff electrode based on inert materials for low-voltage nerve stimulation. Approach. We developed 50 mu m thick stretchable cuff electrodes based on silicone rubber, gold nanowire conductors and platinum coated nanowire electrodes. The electrode performance was characterized under strain cycling to assess the durability of the electrodes. The stimulation capability of the cuff electrodes was evaluated in an in vivo sciatic nerve rat model by measuring the electromyography response to various stimulation pulses. Main results. The stretchable cuff electrodes showed excellent stability for 50% strain cycling and one million stimulation pulses. Saturated homogeneous stimulation of the sciatic nerve was achieved at only 200 mV due to the excellent conformability of the electrodes, the low conductor resistance (0.3 Ohm sq(-1)), and the low electrode impedance. Significance. The developed stretchable cuff electrode combines favourable mechanical properties and good electrode performance with inert and stable materials, making it ideal for low power supply applications within bioelectronic medicine. ; Funding Agencies|Swedish Foundation for Strategic Research, Swedens Innovation Agency (VINNOVA); Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO Mat LiU) [2009 00971]

The renewable-electricity-powered CO2 electroreduction reaction provides a promising means to store intermittent renewable energy in the form of valuable chemicals and dispatchable fuels. Renewable methane produced using CO2 electroreduction attracts interest due to the established global distribution network; however, present-day efficiencies and activities remain below those required for practical application. Here we exploit the fact that the suppression of *CO dimerization and hydrogen evolution promotes methane selectivity: we reason that the introduction of Au in Cu favors *CO protonation vs. C-C coupling under low *CO coverage and weakens the *H adsorption energy of the surface, leading to a reduction in hydrogen evolution. We construct experimentally a suite of Au-Cu catalysts and control *CO availability by regulating CO2 concentration and reaction rate. This strategy leads to a 1.6× improvement in the methane:H2 selectivity ratio compared to the best prior reports operating above 100 mA cm-2. We as a result achieve a CO2-to-methane Faradaic efficiency (FE) of (56 ± 2)% at a production rate of (112 ± 4) mA cm-2. ; This work was supported by the Natural Gas Innovation Fund, the Natural Sciences and Engineering Research Council (NSERC) of Canada, the Natural Resources Canada Clean Growth Program, and the Ontario Research Fund—Research Excellence program. All DFT computations were performed on the Niagara supercomputer at the SciNet HPC Consortium. SciNet is funded by the Canada Foundation for Innovation, the Government of Ontario, the Ontario Research Fund Research Excellence Program, and the University of Toronto. The XPS, TEM/STEM, SEM, and EDX analyses were carried out at the CFI-funded Ontario Centre for the Characterization of Advanced Materials at the University of Toronto. The authors acknowledge the Paul Scherrer Institut, Villigen, Switzerland, for the provision of synchrotron radiation beamtime at beamline SuperXAS of the SLS and would like to thank Dr. Maarten Nachtegaal for assistance. Part of this research used resources of the Advanced Photon Source, an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science by Argonne National Laboratory, and was supported by the U.S. DOE under Contract No. DE-AC02-06CH11357, and the Canadian Light Source and its funding partners. D.S. acknowledges the NSERC E.W.R. Steacie Memorial Fellowship. J.L. acknowledges the financial support from the European Union's Horizon 2020 Research and Innovation program under the Marie Skłodowska-Curie Grant Agreement (MSCA) No. 838686.