Agricultural production structure,market conditions and farmers’nutritional intake in rural China

Nutrition poverty alleviation is an effective measure to improve the nutritional status of economically disadvantaged individuals,fundamentally improving their health and reducing poverty.Based on the Entitlement Theory and using the China Health and Nutrition Survey(CHNS)data,this paper examines the relationship between farmers’nutritional intake,production structure and regional market conditions.Results show that farmers with diversified production have better nutritional intake than those who specialize.Furthermore,the correlation between regional market conditions and nutritional intake varies between economically disadvantaged and non-economically disadvantaged households.Market conditions significantly influence the carbohydrate and fat intake of economically disadvantaged households and are positively associated with the dietary structure and nutritional intake of non-economically disadvantaged ones.Moreover,income is positively correlated with the nutritional intake of non-economically disadvantaged households but not with economically disadvantaged ones.

A Non-orthogonal STFC-OFDM on Frequency-Selective Fading Channels

A new non-orthogonal space-time-frequency code (STFC) was proposed. In conjunction with orthogonal frequency-division multiplexing (OFDM), it is appropriate for the application on frequency-selective fading channels. On the basis of the existing non-orthogonal STC, frequency diversity is studied and a new non-orthogonal STFC is further designed. Monte-Carlo simulations show that the non-orthogonal STFC-OFDM has the advantage of large diversity order, high bandwidth efficiency and better BER performance when compared with the orthogonal STC/STFC-OFDM and non-orthogonal STC-OFDM systems.

ROTATION CONSTELLATION FOR DIFFERENTIAL UNITARY SPACE-TIME MODULATION

A new constellation which is the multiplication of the rotation matrix and the diagonal matrix ac- cording to the number of transmitters is proposed to increase the diversity product, the key property to the performance of the differential unitary space-time modulation. Analyses and the simulation results show that the proposed constellation performs better and 2dB or more coding gain can be achieved over the traditional cyclic constellation.

SIGNAL CONSTELLATIONS DESIGN FOR DIFFERENTIAL UNITARY SPACE-TIME IN MIMO-OFDM SYSTEM OVER FREQUENCY-SELECTIVE FADING CHANNELS

In this paper, the design of signal constellations parameters is studied for Differential Unitary Space-Time Modulation (DUSTM) based on the design criterion of maximizing the diversity product. Further, noninteger searching method for the signal constellation parameters design is proposed in order to get better codes. Experimental results show that under the different Doppler spread and data transmission rate, the proposed design performs better than the previous design using integer parameters in Multiple Input Multiple Output Orthogonal Frequency Division Multiplexing (MIMO-OFDM) system over frequency-selective fading channels.

Recent advances in metal-organic frameworks for catalytic CO_(2) hydrogenation to diverse products

Selective hydrogenation of CO_(2) to high value-added chemicals,not only gives an effective way to reduce the concentration of CO_(2),but also provides the precursors to advance the industrial manufacturing of chemicals and fuels.With the well-defined reticular frameworks and flexible modifiability,metal-organic frameworks(MOFs)can be the ideal platform to construct the enabled catalysts for CO_(2) hydrogenation,because they have shown the great potential for the enhancement of catalytic activity,the precise control of selectivity,and the excellent stability.In this review,we systematically summarize the recent advances in MOFs based catalysts for CO_(2) hydrogenation towards diverse products.Firstly,synthesis strategies for different kinds of MOFs based catalysts are described.Secondly,selective hydrogenation of CO_(2) towards CO and methane is discussed over various metal nanoparticles/MOFs composites.Thirdly,heterogenization and isolation of molecular catalysts by MOFs are elaborated for producing formic acid.Fourthly,selective hydrogenation of CO_(2) toward methanol is discussed in terms of interface structures of Cu,Zn,and metal nodes of MOFs,the synergy between auxiliary sites and noble metal,and tandem catalytic systems of molecular catalysts and Lewis acid sites.Subsequently,the integration of multiple metal sites,promoters,and cocatalysts into MOFs is described for the selective hydrogenation of CO_(2) to C2+products.After those,the key issue about the stability of MOFs based catalysts for CO_(2) hydrogenation reaction is discussed.Finally,the summary and perspective about MOFs based catalysts for selective CO_(2) hydrogenation and mechanism research are proposed.

Dominance by an obligate annual affects the morphological characteristics and biomass production of a planted wetland macrophyte community

Aims Biodiversity-ecosystem function experiments can test for causal relationships between planting diversity and community productivity.Planting diversity is routinely introduced as a design element in created wetlands,yet substantive support for the finding that early diversity positively affects ecosystem functioning is lacking for wetlands.We conducted a 2-year diversity-productivity experiment using freshwater wetland mesocosms to investigate community biomass production as affected by planted macrophyte functional richness.Methods A richness gradient of macrophytes in four emergent wetland plant functional groups was established in freshwater mesocosms for two consecutive years.Species-specific aboveground morphological traits of plant size were measured at peak growth in both years;rooting depth was measured for each species in the second year.Aboveground biomass(AGB)and belowground biomass(BGB)were harvested after peak growth in the second year;first year AGB was estimated from morphological traits in constructed regression equations.Net richness effects(i.e.both complementarity effects and selection effects)were calculated using an additive partitioning method.Important Findings Species richness had a positive effect on community AGB relative to monocultures in the first year.In the second year,mean AGB was significantly reduced by competition in the most species-rich mixtures and all mixtures underyielded relative to the average monoculture.Competition for soil resources was weaker belowground,whereby root distribution at depths>20cm was reduced at the highest richness levels but overall BGB production was not affected.Changes in species biomass were strongly reflected by variation in species morphological traits,and species above and belowground performances were highly correlated.The obligate annual(Eleocharis obtusa),a dominant competitor,significantly contributed to the depression of perennial species’growth in the second growing season.To foster primary productivity with macrophyte richness in early successional communities of created wetlands where ruderal strategies are favored and competition may be stronger than species complementarity,unsystematic planting designs such as clustering the same or similar species could provide protection for some individuals.Additionally,engineering design elements fostering spatial or temporal environmental variability(e.g.microtopography)in newly created wetlands helps diversify the responses of wetland macrophyte species to their environment and could allow for greater complementarity in biomass production.

CONSTRUCTIONS OF UNITARY SPACE-TIME CODES WITH FULL DIVERSITY

The problem of constructing unitary space-time codes with high diversity product has been studied in many prior works.Recently,constructions of parametric fully diverse unitary space-time codes for prime number antennas system have been introduced.In this paper,the authors propose new construction methods based on these constructions.And fully diverse codes of any number antennas are obtained from these constructions.Unitary space-time codes from present constructions are found to have better error performance than many best known ones.

CONSTRUCTIONS OF THREE-TRANSMIT-ANTENNA SPACE-TIME CODES

In this paper, we give design methods for three-transmit-antenna space-time codes which have reasonable parameters. A few examples are given to show that some unitary space-time codes constructed with our methods are better than the previously best-known ones.

A construction of fully diverse unitary space-time codes

Fully diverse unitary space-time codes are useful in multiantenna communications, especially in multiantenna differential modulation. Recently, two constructions of parametric fully diverse unitary space-time codes for three antennas system have been introduced. We propose a new construction method based on the constructions. In the present paper, fully diverse codes for systems of odd prime number antennas are obtained from this construction. Space-time codes from present construction are found to have better error performance than many best known ones.