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Biochar adsorption presents a potential remediation method for the control of hydrophobic organic compounds (HOCs) pollution in the environment. It has been found that HOCs bound on biochar become less bioavailable, so speculations have been proposed that HOCs will persist for longer half-life periods in biochar-amended soil/sediment. To investigate how biochar application affects coupled adsorption-biodegradation, nonylphenol was selected as the target contaminant, and biochar derived from rice straw was applied as the adsorbent. The results showed that there was an optimal dosage of biochar in the presence of both adsorption and biodegradation for a given nonylphenol concentration, thus allowing the transformation of nonylphenol to be optimized. Approximately 47.6% of the nonylphenol was biodegraded in two days when 0.005 g biochar was added to 50 mg/L of nonylphenol, which was 125% higher than the relative quantity biodegraded without biochar, though the resistant desorption component of nonylphenol reached 87.1%. All adsorptive forms of nonylphenol (f
rap, f
slow, f
r) decreased gradually during the biodegradation experiment, and the resistant desorption fraction of nonylphenol (f
r) on biochar could also be biodegraded. It was concluded that an appropriate amount of biochar could stimulate biodegradation, not only illustrating that the dosage of biochar had an enormous influence on the half-life periods of HOCs but also alleviating concerns that enhanced HOCs binding by biochar may cause secondary pollution in biochar-modified environment. 相似文献
4.
Chungwen Wei Eugene Storozynsky A. J. McAdam Kun-Yun Yeh Brian R. Tilton Richard A. Willis Richard K. Barth R. John Looney Edith M. Lord J. G. Frelinger 《Cancer immunology, immunotherapy : CII》1996,42(6):362-368
Human prostate-specific antigen (PSA) has a highly restricted tissue distribution. Its expression is essentially limited
to the epithelial cells of the prostate gland. Moreover, it continues to be synthesized by prostate carcinoma cells. This
makes PSA an attractive candidate for use as a target antigen in the immunotherapy of prostate cancer. As a first step in
characterizing the specific immune response to PSA and its potential use as a tumor-rejection antigen, we have incorporated
PSA into a well-established mouse tumor model. Line 1, a mouse lung carcinoma, and P815, a mouse mastocytoma, have been transfected
with the cDNA for human PSA. Immunization with a PSA-expressing tumor cell line demonstrated a memory response to PSA which
protected against subsequent challenge with PSA-expressing, but not wild-type, tumors. Tumor-infiltrating lymphocytes could
be isolated from PSA-expressing tumors grown in naive hosts and were specifically cytotoxic against a syngeneic cell line
that expressed PSA. Immunization with tumor cells resulted in the generation of primary and memory cytotoxic T lymphocytes
(CTL) specific for PSA. The isolation of PSA-specific CTL clones from immunized animals further demonstrated that PSA can
serve as a target antigen for antitumor CTL. The immunogenicity studies carried out in this mouse tumor model provide a rationale
for the design of methods to elicit PSA-specific cell-mediated immunity in humans.
Received: 4 April 1996 / Accepted: 31 May 1996 相似文献
5.
Cun-Feng Zhao Ran Wei Xian-Chun Zhang 《Cladistics : the international journal of the Willi Hennig Society》2020,36(4):443-445
Here, we publish Lepisorus sect. Paragramma (Blume) C.F. Zhao, R. Wei & X.C. Zhang as a combinatio nova to replace the section name in Zhao et al. (2020), which was published as a status nova and turned out to be an invalid name, because we cited an incorrect basionym. A revised infrageneric classification of Lepisorus also is proposed. 相似文献
6.
Kai Zhang Jun He Claudio Catalano Youzhong Guo Jun Liu Chunhao Li 《Molecular microbiology》2020,113(6):1122-1139
The Lyme disease bacterium Borrelia burgdorferi has 7–11 periplasmic flagella (PF) that arise from the cell poles and extend toward the midcell as a flat-ribbon, which is distinct from other bacteria. FlhF, a signal recognition particle (SRP)-like GTPase, has been found to regulate the flagellar number and polarity; however, its role in B. burgdorferi remains unknown. B. burgdorferi has an FlhF homolog (BB0270). Structural and biochemical analyses show that BB0270 has a similar structure and enzymatic activity as its counterparts from other bacteria. Genetics and cryo-electron tomography studies reveal that deletion of BB0270 leads to mutant cells that have less PF (4 ± 2 PF per cell tip) and fail to form a flat-ribbon, indicative of a role of BB0270 in the control of PF number and configuration. Mechanistically, we demonstrate that BB0270 localizes at the cell poles and controls the number and position of PF via regulating the flagellar protein stability and the polar localization of the MS-ring protein FliF. Our study not only provides the detailed characterizations of BB0270 and its profound impacts on flagellar assembly, morphology and motility in B. burgdorferi, but also unveils mechanistic insights into how spirochetes control their unique flagellar patterns. 相似文献
7.
Jiefeng He Haichao Zhao Dongfeng Deng Yadong Wang Xiao Zhang Haoliang Zhao Zongquan Xu 《Journal of cellular physiology》2020,235(3):2464-2477
This study aimed to identify significant biomarkers related to the prognosis of liver cancer using long noncoding RNA (lncRNA)-associated competing endogenous RNAs (ceRNAs) analysis. Differentially expressed mRNA and lncRNAs between liver cancer and paracancerous tissues were screened, and the functions of these mRNAs were predicted by gene ontology and pathway enrichment analyses. A ceRNA network consisting of differentially expressed mRNAs and lncRNAs was constructed. LncRNA FENDRR and lncRNA HAND2-AS1 were hub nodes in the ceRNA network. A risk score assessment model consisting of eight genes (PDE2A, ESR1, FBLN5, ALDH8A1, AKR1D1, EHHADH, ADRA1A, and GNE) associated with prognosis were developed. Multivariate Cox regression suggested that both pathologic_T and risk group could be regarded as independent prognostic factors. Furthermore, a nomogram model consisting of pathologic_T and risk group showed a good prediction ability for predicting the survival rate of liver cancer patients. The nomogram model consisting of pathologic_T and a risk score assessment model could be regarded as an independent factor for predicting prognosis of liver cancer. 相似文献
8.
Wei Lu 《Evolution; international journal of organic evolution》2020,74(8):1879-1880
What determines the rate at which species adapt to new climatic conditions? Weaver et al. found that the evolution of short larval periods promotes climatic niche evolution in salamanders in the genus Desmognathus. 相似文献
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10.
Dongxue Yin Wei Liu Ningning Zhai Yongzhong Feng Gaihe Yang Xiaojiao Wang Xinhui Han 《PloS one》2015,10(5)
This study investigated the effect of sunlight-dark conditions on volatile fatty acids (VFAs), total ammonium nitrogen (TAN), total alkalinity (TA) and pH during pig manure (PM) digestion and then the subsequent influence on biogas yield of PM. PM1 and PM2 were performed in a transparent reactor and a non-transparent reactor, respectively. Two sets of experiments were conducted with a temperature of 35.0±2.0 °C and a total solid concentration of 8.0% to the digestion material. The dynamic change of the four parameters in response to sunlight-dark conditions resulted in variations of the physiological properties in the digester and affected the cumulative biogas production (CBP). PM1 obtained higher CBP (15020.0 mL) with a more stable pH and a lower TAN concentration (1414.5 mg/L) compared to PM2 (2675.0 mL and 1670.0 mg/L, respectively). The direct path coefficients and indirect path coefficients between the four parameters and CBP were also analyzed. 相似文献