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The performance of an over 10 times larger microbial fuel cell (MFC) with double cloth electrode assemblies (CEAs) during 63 days of continuous operation demonstrates that the excellent performance of CEA-MFCs can be further improved during scale-up. With a new separator material and U-shaped current collectors, the larger MFC produced a maximum power density of 4.30 W m À2 at a current density of 16.4 A m À2 , corresponding to a volumetric power density of 2.87 kW m À3 at 10.9 kA m À3 for a double CEA-MFC. The high current density led to a high average coulombic efficiency (CE) of 83.5% as well as a high potential COD removal rate of 93.5 kg m À3 d À1 . Energy efficiency is estimated in the range of 21-35%, depending on the operating voltage. The low-cost non-woven cloth separator further reduced the anode-cathode spacing and internal resistance, greatly enhancing the power generation. The enhanced self-production of bicarbonate buffer, which can be manipulated by adjusting hydraulic retention time and substrate concentration, also contributed to the improved performance. The results demonstrate the great potential of MFC technology in competing with methanogenic anaerobic digestion for waste-to-electricity and wastewater treatment.

Food waste has been regarded as the main source of various environmental pollution in Korea due to the high volatile solids (VS) and moisture content caused by the features of dietary habits. The feasibility of food waste as a co-substrate in anaerobic digestion of sewage sludge was investigated in mesophilic and thermophilic conditions using batch tests. Cumulative methane production, dissolved organic carbon (DOC) and volatile fatty acids (VFA) were monitored to find the optimal mixing ratios of food waste and sewage sludge for the enhanced performance of co-digestion. It was observed that adequately mixed food waste led to the enhanced methane production both at mesophilic and thermophilic conditions. However, a conventional linear regression conducted for the optimisation of co-substrate mixing ratios was not accurate in describing exact methane production trends of co-digestion because of the different biodegradability of substrates. Therefore, a remodified Gompertz equation showing nonlinear relationship between variables was developed to find exact information with the same experimental data obtained at 2g VS/l generally used in biochemical methane potential (BMP) tests. Based on an influential parameter, methane production rate (MPR), the optimal mixing ratios of food waste were 39.3% and 50.1% in mesophilic and thermophilic conditions, respectively. To confirm the application of the remodified Gompertz equation, secondary batch tests were conducted with the substrate concentrations of 1-4g VS/l. In overall range tested, the confident mixing ratios of food waste was adjusted to 30-40% and 40% in mesophilic and thermophilic conditions, respectively. The most significant factor for enhanced performance was the improved organic carbon content provided by additional food waste.

Becuase 40% of human papillomavirus (HPV) infections are mixed infections, the accurate identification of high-risk HPV genotypes in mixed infections is important for defining a woman's risk for progression to cervical cancer. Thus, advanced Luminex-based HPV genotyping has been developed to simultaneously detect the presence of multiple HPV types. Here, we describe the development of a Luminex-based HPV genotyping that combines polymerase chain reaction amplification with hybridization to fluorescencelabeled polystyrene bead microarrays (Luminex suspension array technology). New HPV type-specific oligonucleotide probes and YBT L1/GP6-1 primers were used to detect the HPV types in 132 clinical samples. We simultaneously evaluated the usefulness of this technique on clinical samples. We detected 15 specific HPV types (6, 16, 18, 31, 35, 42, 51, 52, 55, 56, 58, 59, 66, 67 and 68) examined with specificity without known cross-reaction to other HPV types. The detection limit for the different HPV types was above 500 plasmids. (1) individuals may be infected with more than one type at a time.(2) Because most HPV infections have no visible signs or symptoms, (3) the development of detection tools for HPV identification in asymptomatic patients has been very important. (4) Several HPV DNA detection methods have been described during the last decade, each of which allows the detection of a wide spectrum of HPV types, such as DNA amplification-based methods. Due largely to routine screening using Pap tests, the number of deaths attributed to cervical cancer continues to drop nearly 4% annually. However, the Pap smear has some weaknesses, not least of which is its limited sensitivity for detection of cancer precursors.(5) Therefore, the false-negative rate of the Pap smear ranges from 20 to 30% when cytology is used alone. In addition, there is a false-positive rate of 5-15%.(6 -8) To carry out HPV genotyping, a reliable, FDA-approved test to distinguish the specific HPV types will need to be developed and validated. A DNA-based technology, the Hybrid Capture II HPV test, has been used to detect 13 high-risk types of HPV. (9,10) However, this routine test is not recommended for women under the age of 30 years unless they have atypical or equivocal Pap test results. In addition, despite its high sensitivity, false-negative results are known to occur for histologically confirmed cervical intraepithelial neoplasia (CIN)2 or CIN3 cases, with its impossibility to perform genotyping. (11,12) Therefore, the current techniques available for detection of HPV types all have shown limited ability for complete detection; there is no single technique that provides complete detection to date. Therefore, a new and improved HPV assay that is highly sensitive and reproducible is required. Multiplex technology is a new method that is based on fluorescent bead technology, and allows simultaneous detection of nucleic acids against up to 100 different HPV types. (13,14) Recently, this technology has been used for the genotyping of HPV types u...

This study was conducted to evaluate the performance of an innovative two-stage process, BIOCELL, that was developed to produce hydrogen (H 2 ) and methane (CH 4 ) from food waste on the basis of phase separation, reactor rotation mode, and sequential batch technique. The BIOCELL process consisted of four leaching-bed reactors for H 2 recovery and post-treatment and a UASB reactor for CH 4 recovery. The leaching-bed reactors were operated in a rotation mode with a 2-day interval between degradation stages. /kg VS added , respectively. Moreover, the output from the posttreatment could be used as a soil amendment. The BIOCELL process proved to be stable, reliable, and effective in resource recovery as well as waste stabilization. INTRODUCTIONThe generation of food waste reaches 11,237 t/day in Korea, accounting for 23.2% of municipal solid waste. 1 Because of its high volatile solids (85-95%) and moisture content (75-85%), food waste causes decay, odor, and leachate in collection and transportation. Most food