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Land surface temperatures (LSTs) at high-spatial resolution are significant for hydrological, meteorological, and ecological studies. An alternative method to obtain LSTs at a high-spatial resolution is to downscale LSTs from a coarse resolution to a finer resolution. In this article, we propose a new algorithm based on temperature and vegetation dryness index in combination with elevation correction to downscale Moderate Resolution Imaging Spectroradiometer LST data from 1000 m to 90 m. The performance of the algorithm was assessed using Advanced Spaceborne Thermal Emission and Reflection Radiometer LST data as a reference LST data set. The results show that the proposed algorithm is superior to the temperature sharpening algorithm, which is widely used nowadays. The root mean square error and mean absolute error values of downscaled LSTs decrease from 3.1 K (2.4 K) to 2.8 K (2.3 K). [ABSTRACT FROM AUTHOR]

In this paper, a phase-encoded measurement device independent quantum key distribution (MDI-QKD) protocol without a shared reference frame is presented, which can generate secure keys between two parties while the quantum channel or interferometer introduces an unknown and slowly time-varying phase. The corresponding secret key rate and single photons bit error rate is analysed, respectively, with single photons source (SPS) and weak coherent source (WCS), taking finite-key analysis into account. The numerical simulations show that the modified phase-encoded MDI-QKD protocol has apparent superiority both in maximal secure transmission distance and key generation rate while possessing the improved robustness and practical security in the high-speed case. Moreover, the rejection of the frame-calibrating part will intrinsically reduce the consumption of resources as well as the potential security flaws of practical MDI-QKD systems. [ABSTRACT FROM AUTHOR]

Measurement device independent Quantum Key Distribution (MDI-QKD), is immune to all attacks on detection and achieve immense improvement with respect to quantum key distribution system security. However, Bell state measurement (BSM), the kernel processing in MDI-QKD, can only identify two of the four Bell states, which limits the efficiency of the protocol. In this paper, a modified MDI-QKD with hybrid qubit is proposed to provide a major step towards answering this question. The hybrid qubits, which are composed of single photon qubit qubits and coherent qubit, are sent to the quantum relay to perform parallel BSMs synchronously and bit flip can be easily operated to complete the whole key distribution process. The secure key rate can be improved with our modified protocol owing to the higher success probability of BSM, which is increased by adding the parity check of coherent qubit. Furthermore, though our protocol requires photon number resolving detectors, the BSM of coherent state could be instead implemented using squeezed state which makes our scheme practical with state-of-the-art devices. [ABSTRACT FROM AUTHOR]

This study is to evaluate the association between IL-8 -251A/T polymorphism and lung cancer risk in diverse populations. We performed a meta-analysis of six case-control studies that included 3,265 lung-cancer cases and 3,607 case-free controls. Overall, results showed that the IL-8 -251A/T polymorphism was not associated with a significantly increased risk of lung cancer in all genetic models. However, stratified by ethnicity, a significantly increased risk was found among Asians. In conclusion, IL-8 -251A/T polymorphism is associated with lung cancer susceptibility in Asians and the -251 A allele may increase risk of lung cancer in Asians. [ABSTRACT FROM AUTHOR]

Measurement-device-independent quantum key distribution (MDI-QKD) is immune to all the detection attacks, thus when it is combined with the decoy-state method, the final key rate can be obtained by estimating the gain and quantum bit error rate for various input photon numbers. In this paper, we propose to perform MDI-QKD with odd coherent state (OCS) and compare the results with weak coherent source scenario. Our simulation indicates that both the secure key rate and transmission distance can be improved evidently with OCS owing to the lower probability of multi-photon events of the OCS. Furthermore, we apply the finite key analysis to the decoy-state MDI-QKD with OCS and obtain a practical key rate. [ABSTRACT FROM AUTHOR]

As international pressure on China's policy concerning its increasing investments in Iran grows, the Chinese leadership has to painfully balance its impulse toward energy and economic cooperation with Iran against other important interests, including enhancing its image as a responsible big country. After analyzing the evolution of China–Iran energy relations, this paper tries to answer the question of how China has responded to the intensification of US-led sanctions against Iran, what merits and shortcomings China's attempts to balance or reconcile its interests in Iran might create, and what options China can take to deal with a possible oil crisis. [ABSTRACT FROM AUTHOR]

The history of the conflicting maritime claims in the South China Sea, focussing particularly on the recent disputes between China and Vietnam/the Philippines. The author describes how external actors, principally the US, but also India and Japan, have been drawn in as a counterweight to China. He then goes on to assess the possible impact of this political dispute on the essentially economic relationship between China and ASEAN. His conclusion is that the economic relationship is likely to prove enduring. [ABSTRACT FROM PUBLISHER]

We investigated the reaction mechanism and thermochemical property of conjugated dienes or mono-olefins with nickel dithiolenes (Ni(S2C2R2)2) using density functional theory. The reactions between conjugated dienes and nickel dithiolenes are concerted reactions. The thermochemical property study shows that the introduction of electron-withdrawing groups (–CF3 or –CN) to nickel dithiolene (Ni(S2C2H2)2) not only significantly lowers the activation energy barrier but also strongly stabilises the products. The introduction of electron-donating group (–CH3) to butadiene has the same effect. So, we conclude that the reactions between nickel dithiolenes and conjugated dienes are electrophilic cycloaddition. Mono-olefins can add to nickel dithiolenes through interligand pathway, which is a two-step process or through intraligand pathway, which is a one-step process. The thermochemical property study shows that the activation enthalpy for the reaction of butadiene with Ni(S2C2(CF3)2)2 is much lower than those of C4 mono-olefins with Ni(S2C2(CF3)2)2 for both interligand addition and intraligand addition. The Gibbs free energy for the reaction of butadiene with Ni(S2C2(CF3)2)2 is also more favourable than those of C4 mono-olefins with Ni(S2C2(CF3)2)2. It is the very preferential pathway for Ni(S2C2(CF3)2)2 to bind butadiene than C4 mono-olefins. [ABSTRACT FROM PUBLISHER]

This article seeks to evaluate the impact of India and China on world energy markets by setting their future energy demands, principally for coal and oil, in the context of their domestic supply potential. After examining their approach to energy efficiency, the author concentrates on their energy diplomacy and the way in which they have sought to enhance their security of supply by targeting exporting countries, often those with a somewhat fraught relationship with the west. He concludes that it is in their interest to further strengthen their co-operation and avoid competition which simply drives up the price they pay for oil. [ABSTRACT FROM AUTHOR]

The influences induced by various terminal substituents and solvents on the reaction mechanism and chemical dynamics of complexing ethylene with Ni dithiolene are theoretically studied by using B3LYP method and Onsager model. It is shown that the reaction should be a two-step process, and the first step is the rate-determining step. We find that the rate constant of the rate-determining step becomes small when the electron-donating ability of the substituents is increased, while it becomes large when the electron-withdrawing ability of the substituents is increased. Subsequently, we consider the solvent effects on the reaction adding ethylene to the simplified hydrogen-substituted nickel dithiolene. It is found that the solvents will make slight changes to the geometries of the reactants, transition states, intermediates and products. However, the corresponding molecular dipole moments become large with the increase of the solvent polarity, which is beneficial to accelerate the reaction. Moreover, we show that, as the solvent polarity becomes large, the activation energies of the reaction decrease exponentially, while the reaction rate constants increase exponentially. These results demonstrate that in polar solvents, the reaction complexing ethylene with Ni dithiolene may become easier and faster to occur, and the product rate is improved. We believe that this research can be seen as a reference for complex and solvent selection in olefin separation process. [ABSTRACT FROM AUTHOR]

A computational study was conducted on expanding spherical premixed flames to investigate the dynamics of the stretch-affected, one-dimensional, pulsating instability at elevated pressures and temperatures. Rich H 2 /air mixtures were investigated using a time-dependent, spherically symmetric code with detailed chemistry, transport, and radiation submodels. The study shows that the region of instability in the pressure versus equivalence ratio domain for outwardly propagating flames is significantly narrowed when compared with that for planar flames due to the presence of the local ignition limit despite stretch-induced pulsation modifying the other boundary. Moreover, a region of one oscillation ending in extinction (even under adiabatic conditions which are not present in planar flames) has been discovered. However, similar to planar flames, radiative loss in outwardly propagating spherical flames reduces the region of instability due to transient extinction. Interestingly, this limit lies next to and just below the concentration limit for ignition. For the same ignition/extinction reasons, the region of instability is expanded at elevated temperatures due to increased flammability. The calculations show that the dynamics of spherically expanding flames is significantly different than that for planar flames. As a result, the near-limit phenomenon is extremely geometry dependent, thereby having an impact on practical considerations of flammability and stability. [ABSTRACT FROM AUTHOR]

The article reports that the surge of subregional economic cooperation in East Asia is a response to the economic globalization caused by the liberalization of trade and investment since the 1980s. These arrangements have a strong inclination toward open regionalism in contrast to the discriminatory regionalism represented by the European Union and the North American Free Trade Area. Some scholars, such as Mohamed Ariff, suggest that the ASEAN Free Trade Area does not have the discriminatory effects that economists often predict in conventional analysis of regional trade agreements, and they believe subregional economic cooperation in East Asia does not conflict with globalization. In fact, under the policy of export-oriented industrialization dependent on foreign direct investment, open regionalism is the only possible way of development. The East Asian countries, particularly the ASEAN countries and China, have preferred open regionalism. They have been heavily dependent on developed countries like Japan, the U.S., and European Union members as their major markets and main sources of capital and technology.