Considerations on the methane correction factor and fraction of methane parameters in the IPCC first-order decay model for active aeration landfills.

Understanding the behavior of organic carbon in municipal solid waste landfills is a major challenge for estimating methane (CH) emissions using the Intergovernmental Panel on Climate Change (IPCC) first-order decay (FOD) model. According to the IPCC guidelines, the default values of CH correction factor (MCF) and fraction of CH (F) for active aeration landfills are set as 0.4 and 0.

Alkali-Metal-Intercalated Percolation Network Regulates Self-Assembled Electronic Aromatic Molecules.

In the continuously growing field of correlated electronic molecular crystals, there is significant interest in addressing alkali-metal-intercalated aromatic hydrocarbons, in which the possibility of high-temperature superconductivity emerges. However, searching for superconducting aromatic molecular crystals remains elusive due to their small shielding fraction volume. To exploit this potential, a design principle for percolation networks of technologically important film geometry is indispensable.

Is Immediate Postoperative Mechanical Axis Associated with the Revision Rate of Primary Total Knee Arthroplasty? A 10-Year Follow-up Study.

Background: Achieving neutral limb alignment during total knee arthroplasty (TKA) has been considered an important determinant in the long-term prosthesis survival. The purpose of this study was to evaluate the association between the immediate postoperative mechanical alignment of the lower limb and the rate of revision TKA by comparing an acceptable mechanical axis group (within ± 3° from neutral alignment) and an outlier group (> 3° deviation from neutral alignment).

Methods: Between 2000 and 2006, clinical and radiographic data of 334 primary TKAs were retrospectively reviewed to determine the 10-year Kaplan-Meier survival rate.

Methods for determining the methane generation potential and methane generation rate constant for the FOD model: a review.

In the first order decay (FOD) model of landfill methane generation, the methane generation potential ( L) and methane generation rate constant ( k) for both bulk municipal solid waste (MSW) and individual waste components have been determined by a variety of approaches throughout various literature. Differences in the determination methods for L and k are related to differences in our understanding of the waste decomposition dynamics. A thorough understanding of the various available methods for determining L and k values is critical for comparative study and the drawing of valid conclusions.

Estimation of methane emission flux at landfill surface using laser methane detector: Influence of gauge pressure.

The aim of this study was to investigate the possibility of measuring methane emission fluxes, using surface methane concentration and gauge pressure, by analyzing the influence of gauge pressure on the methane emission flux and the surface methane concentration, as well as the correlation between the methane emission flux and surface methane concentrations. The surface methane concentration was measured using a laser methane detector. Our results show a positive linear relationship between the surface methane concentration and the methane emission flux.

Acceleration of aged-landfill stabilization by combining partial nitrification and leachate recirculation: a field-scale study.

Leachate recirculation for rapid landfill stabilization can result in the accumulation of high-strength ammonium. An on-site sequencing batch reactor (SBR) was therefore, applied to oxidize the ammonium to nitrite, which was then recirculated to the landfill for denitrification to nitrogen gas. At relatively higher ammonium levels, nitrite accumulated well in the SBR; the nitrite was denitrified stably in the landfill, despite an insufficient biodegradable carbon source in the leachate.

Loss of heterozygosity of tumor suppressor genes (p16, Rb, E-cadherin, p53) in hypopharynx squamous cell carcinoma.

Objective: Microsatellite alterations, especially those that cause loss of heterozygosity (LOH), have recently been postulated as a novel mechanism of carcinogenesis and a useful prognostic factor in many kinds of malignant tumors. However, few studies have focused on a specific site, hypopharynx. The aim of this study was to evaluate the relationship between LOH and hypopharyngeal squamous cell carcinoma (HPSCC).

Comparison of clinical characteristics between primary and secondary paranasal mucoceles.

Purpose: Paranasal sinus mucocele is a benign, expansile mass which can occur as a result of trauma or spontaneous obstruction of a sinus tract. The purpose of this study was to describe and compare the clinical characteristics of primary mucoceles occurring in patients with no previous sinus surgery history or known cause of mucoceles and secondary mucoceles resulting as a complication following endoscopic sinus surgery or the Caldwell-Luc operation.

Materials And Methods: We performed a retrospective chart review of 33 cases of primary mucoceles and 60 cases of secondary mucoceles which were diagnosed and surgically corrected between 1996 and 2008.