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Although in recent years nonhost resistance has attracted considerable attention for its broad spectrum and durability, the genetic and mechanistic components of nonhost resistance have not been fully understood. We used molecular and histochemical approaches including quantitative PCR, chromatin immunoprecipitation, and 3,3'-diaminobenzidine and aniline blue staining. The evolutionarily conserved histone acetyltransferase complex Elongator was identified as a major component of nonhost resistance against Xanthomonas citri subsp. citri (Xcc) and Pseudomonas syringae pv. phaseolicola (Psp) NPS3121. Mutations in Elongator genes inhibit Xcc-, Psp NPS3121- and/or flg22-induced defense responses including defense gene expression, callose deposition, and reactive oxygen species (ROS) and salicylic acid (SA) accumulation. Mutations in Elongator also attenuate the ROS-SA amplification loop. We show that suppressed ROS and SA accumulation in Elongator mutants is correlated with reduced expression of the Arabidopsis respiratory burst oxidase homologue AtrbohD and the SA biosynthesis gene ISOCHORISMATE SYNTHASE1 (ICS1). Furthermore, we found that the Elongator subunit ELP2 is associated with the chromatin of AtrbohD and ICS1 and is required for maintaining basal histone H3 acetylation levels in these key defense genes. As both AtrbohD and ICS1 contribute to nonhost resistance against Xcc, our results reveal an epigenetic mechanism by which Elongator regulates nonhost resistance in Arabidopsis.

DEFORMED ROOT AND LEAVES1 (DRL1) is an Arabidopsis homologue of the yeast TOXIN TARGET4 (TOT4)/KILLER TOXIN‐INSENSITIVE12 (KTI12) protein that is physically associated with the RNA polymerase II‐interacting protein complex named Elongator. Mutations in DRL1 and Elongator lead to similar morphological and molecular phenotypes, suggesting that DRL1 and Elongator may functionally overlap in Arabidopsis. We have shown previously that Elongator plays an important role in both salicylic acid (SA)‐ and jasmonic acid (JA)/ethylene (ET)‐mediated defence responses. Here, we tested whether DRL1 also plays a similar role as Elongator in plant immune responses. Our results show that, although DRL1 partially contributes to SA‐induced cytotoxicity, it does not play a significant role in SA‐mediated expression of PATHOGENESIS‐RELATED genes and resistance to the virulent bacterial pathogen Pseudomonas syringae pv. maculicola ES4326. In contrast, DRL1 is required for JA/ET‐ and necrotrophic fungal pathogen Botrytis cinerea‐induced defence gene expression and for resistance to B. cinerea and Alternaria brassicicola. Furthermore, unlike the TOT4/KTI12 gene which, when overexpressed in yeast, confers zymocin resistance, a phenotype of the tot4/kti12 mutant, overexpression of DRL1 does not change B. cinerea‐induced defence gene expression and resistance to this pathogen. Finally, DRL1 contains an N‐terminal P‐loop and a C‐terminal calmodulin (CaM)‐binding domain and is a CaM‐binding protein. We demonstrate that both the P‐loop and the CaM‐binding domain are essential for the function of DRL1 in B. cinerea‐induced expression of PDF1.2 and ORA59, and in resistance to B. cinerea, suggesting that the function of DRL1 in plant immunity may be regulated by ATP/GTP and CaM binding.

The migration of rural laborers into cities for employment has been one of the main driving forces of China's economic growth over the past three decades. Based on a dataset collected by the Ministry of Agriculture of China from 2003 to 2007, this paper examines the impact of health on the earnings of migrant workers engaging in physically-intensive work requiring good health. Our findings indicate that a poor health status not only weakens the incentive of rural laborers to participate in the migrant labor force but also significantly reduces their earnings. A migrant worker in poor health only earns 67 percent of what a healthy worker makes. Among all the human capital characteristics and family economic factors, health status is the most influential on earnings for less educated workers. Labor productivity has a greater impact on earnings than the annual number of days that a person works. Ongoing health-care reforms aimed at the improvement of the health-care services available to rural laborers are urged to help reduce poverty in rural China.

Background Nipple adenoma is a rare and benign type of breast tumour. Because of the lack of proper understanding, it is easily overlooked and misdiagnosed by doctors. The aim of the study is to improve clinicians' awareness of the disease. Methods Evaluation of the complaints such as blood discharge or nodules on the nipple was done with physical examination, ultrasonography and cytologic evaluation (discharge cytology and curettage cytology). Resection of part of the nipple containing the tumour was performed in 11 of the 12 patients included in this study. Results Physical examination revealed nodules palpable inside the nipples in all 12 cases. However, a hypoechoic nodule was detected unilaterally inside the nipple only in three of 11 patients examined by ultrasonography. It was worth noting that six patients had cytology performed (one case on nipple discharge and five cases on curettage) and that all six had abnormal results. Cytology is often atypical or suspicious but the ultimate pathology is benign. No post-operative recurrence was observed in any of the patients. Conclusions Physical examination and diagnostic studies are important part of the diagnostic workup, but since cytological assessment often yields atypical cells, surgical treatment and pathologic evaluation are the only approach for definitive diagnosis to rule out a potential malignancy.

Natural resource economists have paid great attention to irrigation water allocations among competing users. However, the intrauser allocation problem is greatly understudied. As irrigation becomes increasingly capital-intensive, inefficient within-field allocation and ill-designed water-conservation policy can bring considerable value loss to the water resource. We offer a comprehensive treatment of the economic problem of the intrauser allocation of a limited amount of irrigation water. A framework is provided for determining optimal irrigation intensity and extensity in both static and dynamic settings. An empirical application in West Texas cotton production demonstrates model implementation and offers new insights into the water-saving potential of government-sponsored cost-share programs for promoting high-efficiency irrigation adoption.

A new soluble and dopable copolymer consisting of 3′,4′-dibutyl-2,2′:5′,2″-terthiophene and phenylene-vinylene units has been designed and prepared via a Wittig reaction. This title copolymer is soluble in common organic solvents such as THF and CHCl 3 , and can be doped with iodine achieving an electrical conductivity of about 3.2 × 10 −2 S/cm at room temperature. Films of this copolymer are electroactive and turn reversibly and rapidly from red to green-blue upon doping and undoping electrochemically.