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A growing body of studies examined the effects of health shocks during early childhood and in-utero in developing countries. However, the related research on mental health is limited. In this artic...

The great migration from Chinese farms to cities during the past several decades ranks among the most economically consequential of modern population movements. We use a national sample of rice-producing Chinese households to examine the effects of that migration on agricultural production. Our assessment involves evaluating four alternative theories of labour market equilibrium in the framework of an expanded agricultural household model. Migration’s farm production impacts appear to be slight, not on account of farm labour market perfections or remittance-financed technological improvements, but by substituting a reduction in leisure and other low-return activities for lost labour.

A model is introduced to answer three questions pertaining to site-specific nutrient management in production of orchard crops: which input factors of crop production are limiting yield; what action should be taken to remove the limiting factors; and what is the potential gain in revenue from taking the action. Our model captures the essence of the law of the minimum in that yield and revenue increase only if the limiting nutrients are adjusted. An example of pear trees shows how to implement the method.

The mononuclear palladium(II) complex trans-[PdCl2(PhPPy2)2] (1) reacts with [Cu(CH3CN)4]ClO4 to afford the heterobinuclear [(PhPPy2)2PdCuCl2]ClO4·2CH3CN (2), bridged by two PhPPy2 ligands in a new mode. Complex 2 crystallizes in space group P21/c with a = 12.947(1), b = 9.142(1), c = 33.454(2) A, β = 99.698(1)°. The copper(I) and palladium(II) ions in 2 adopt distorted tetrahedral and square-planar geometry, respectively. At room temperature, the complex is photoluminescent in solution.

N 2-2-Hydroxybenzalmethylene-O,O′-diethylphosphorohydrazonothionate (HL) and its three complexes (ML2·H2O) with nickel(II), copper(II) and zinc(II) have been prepared and identified. The crystal structure of NiL2·H2O has been determined. Crystal data: triclinic, space group P1, a=12.064(4), b=8.692(2), c=7.184(2) A, α=101.34(3), β=94.92(3), γ=103.81(0)°, Z=1, V=710.3(3) A3, Dc= 1.448 g·cm−3,µ=1.65 mm−1, R=0.065, Rw=0.068. The coordination geometry of Ni(II) in the complex is almost a square-planar. The test results of biological activity have shown that these compounds possess some activities of scavenging superoxide free radicals, as acaricides and insecticides.

The Schiff base N-salicylidene-O.S-dimethylthiophosphorylimine (HSMa) and its complexes with copper(II), zinc(II) and nickel(II) have been synthesized. All new compounds have been characterized by elemental analyses, conductivity measurements, infrared and electronic spectra. 1H NMR, 31P NMR and MS have also been used to identify the Schiff base. It has been found that the Schiff base behaves as a bidentate ligand in coordination with the metal ions through its imino nitrogen and phenolic oxygen in the expected mode. Preliminary results of insecticidal activity tests show that all of the synthesized compounds have much higher pesticidal rates on poisoning Aphis fabae and Metatetranychus ulmi, compared with methamidophos (Ma), a commercial pesticide, which is one of the starting materials for the preparation of the Schiff base in this work (Fig. 1).