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Currently, fossil fuels such as oil, coal, and natural gas are the world's primary energy sources. However, it is anticipated that these energy sources will be depleted in less than 100 years. As such, the development of new energy technologies is urgently needed. Biomass is one of the earliest sources of energy, and is used especially in rural areas where it is often the only one that is accessible and affordable. With the depletion of fossil fuels and increasing environmental degradation, biomass energy is attracting increasing attention around the world. Compared with fossil fuel, biomass is carbon neutral and sustainable, and has a smaller greenhouse gas footprint and lower SO2 emission levels. In addition, biomass energy remains the only renewable green energy that can be stored and transported. A number of countries have developed mature and proven combustion technologies, but these technologies are mainly based on wood biomass fuels. Unlike these developed countries, China is a large agricultural country with a limited amount of available firewood. As such, foreign experience cannot be fully applied in China. Although biomass fuels typically have relatively low fuel-N contents, this fuel-N between 70%-100% mass fraction is converted to NOx during combustion. In addition, the combustion of straw and other biomass fuels emits more NOx than wood fuels. In recent years, the air quality in China has become a serious public health concern, and NOx is a widespread atmospheric pollutant with significant impacts on human health and the economy. In this paper, an overview of biomass combustion technologies and NOx control systems in China and around the world was presented, and their advantages and disadvantages were summarized. The main bottleneck was identified in NOx control technologies with respect to biomass boilers in China and the development of new technologies in this field was predicted.

The estimated prevalence of hepatitis C virus (HCV) infection in the US is 1.8 %. Data are limited on the clinical profile of the disease at first presentation and dynamic follow-up of ALT level, especially in publicly-funded patients. This information is critical for optimal management of these patients. The present study is aimed to assess the clinical profiles of chronic hepatitis C (CHC) at first presentation and clinical implication of dynamic follow-up of ALT level in a county medical center setting. A total of 294 patients were selected from the population consecutively evaluated in the Hepatitis Clinic at Los Angeles County-USC Medical Center between Jan. 1990 and Dec. 1998. Ethnicity of the patients was Hispanics-49.0%, Caucasian-28.6%, African American-13.6%, and Asian-8.8%. Risk factors were identifiable in 84.0% of patients, and injection drug use (IDU) represented the leading risk factor for HCV acquisition (47.4%). History of alcoholism was present in 39.1%. The initial clinical diagnoses were chronic hepatitis 76.9%; compensated cirrhosis 20.4%; and decompensated cirrhosis 2.7%. Elevation of ALT, alpha fetoprotein (AFP), ferritin, and anti-nuclear antibody (ANA) titer were seen in 219/294 (74.5%), 60/194 (30.9%), 20/83 (24.1%), and 35/97 (36.1%) patients, respectively. Anti-HBc (total) test was positive in 65/129 (50.5%) patients. The presence of cirrhosis was significantly associated with age greater than 55 years at entry, female gender, non-African American ethnicity, history of transfusion, lower level of albumin and elevated level of AFP. Longitudinal observation of ALT changes in 178 patients who had neither evidence of cirrhosis at entry nor received interferon treatment showed persistently normal, intermittently or persistently elevated ALT level in 15.2%, 38.3%, and 46.6% patients, respectively. The frequency of developing clinical evidence of cirrhosis during follow-up was significantly higher in patients with persistently (16.0%) or intermittently (7.0%) elevated ALT than that in patients with persistently normal ALT (4.0%). In conclusion, the present study analyzed the clinical profiles of CHC, assessed risk factors for developing cirrhosis, and demonstrated the clinical value of dynamic follow-up of ALT level in a cohort of publicly-funded patients. These data have major implications in designing optimal strategies for disease management, antiviral therapy, and screening for hepatocellular carcinoma in patients with CHC.

Bladder cancer is the most common malignancy of the urinary tract and arising from the epithelial lining of the urinary bladder. Resistance to cytotoxic therapies is associated with overexpression of oncogenic proteins; including HER2, and Akt in chemotherapy resistance of bladder cancer. Various studies demonstrated that curcuminoids, the most important active phenolic compounds of turmeric (Curcuma longa), have anti‐tumor activities in a wide range of human malignant cell lines. The aim of this study is to evaluate whether curcuminoids (curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin) could repress the expression of HER2 in HER2‐overexpressing bladder cancer cells. Among the test compounds, DMC significantly suppressed the expression of HER2, and preferentially inhibited cell proliferation and induced apoptosis in HER2‐overexpressing bladder cancer cells. DMC decreases HER2 level through inhibiting the interaction of HER2 and Hsp90. Our study also indicated that DMC showed additive activity in combination with chemotherapeutic agents, including paclitaxel and cisplatin. These findings show that DMC should be developed further as a new antitumor drug candidate for treatment of HER2‐overexpressing bladder cancer. [ABSTRACT FROM AUTHOR]

Abstract Background Association testing is a powerful tool for identifying disease susceptibility genes underlying complex diseases. Technological advances have yielded a dramatic increase in the density of available genetic markers, necessitating an increase in the number of association tests required for the analysis of disease susceptibility genes. As such, multiple-tests corrections have become a critical issue. However the conventional statistical corrections on locus-specific multiple tests usually result in lower power as the number of markers increases. Alternatively, we propose here the application of the longest significant run (LSR) method to estimate a region-specific p-value to provide an index for the most likely candidate region. Results An advantage of the LSR method relative to procedures based on genotypic data is that only p-value data are needed and hence can be applied extensively to different study designs. In this study the proposed LSR method was compared with commonly used methods such as Bonferroni's method and FDR controlling method. We found that while all methods provide good control over false positive rate, LSR has much better power and false discovery rate. In the authentic analysis on psoriasis and asthma disease data, the LSR method successfully identified important candidate regions and replicated the results of previous association studies. Conclusion The proposed LSR method provides an efficient exploratory tool for the analysis of sequences of dense genetic markers. Our results show that the LSR method has better power and lower false discovery rate comparing with the locus-specific multiple tests.

Background: The medicinal plant, Catharanthus roseus (C. roseus), accumulates a wide range of terpenoid indole alkaloids (TIAs). Ethylene (ET) and methyl-jasmonate (MeJA) were previously reported as effective elicitors for the production of various valuable secondary metabolites of C. roseus, while a few ET or MeJA induced transcriptomic research is yet reported on this species. In this study, the de-novo transcriptome assembly of C. roseus is performed by using the next-generation sequencing technology. Results: The result shows that phenolic biosynthesis genes respond specifically to ET in leaves, monoterpenoid biosynthesis genes respond specifically to MeJA in roots. By screening the database, 23 ATP-binding cassette (ABC) transporter partial sequences are identified in C. roseus. On this basis, more than 80 key genes that encode key enzymes (namely TIA pathway, transcriptional factor (TF) and candidate ABC transporter) of alkaloid synthesis in TIA biosynthetic pathways are chosen to explore the integrative responses to ET and MeJA at the transcriptional level. Our data indicated that TIA accumulation is strictly regulated by the TF ethylene responsive factor (ERF) and bHLH iridoid synthesis 1 (BIS1). The heatmap, combined with principal component analysis (PCA) of C. roseus, shows that ERF co-expression with ABC2 and ABC8 specific expression in roots affect the root-specific accumulation of vinblastine in C. roseus. On the contrast, BIS1 activities follow a similar pattern of ABC3 and CrTPT2 specific expression in leaves, which affects the leaf-specific accumulation of vindoline in C. roseus. Conclusions: Results presented above illustrate that ethylene has a stronger effect than MeJA on TIA induction at both transcriptional and metabolite level. Furthermore, meta-analysis reveals that ERF and BIS1 form a positive feedback loop connecting two ABC transporters respectively and are actively involved in TIAs responding to ET and MeJA in C. roseus. [ABSTRACT FROM AUTHOR]