Long-term and residual settlement behaviour of a multi-staged municipal solid waste landfill, Republic of Korea.

In this study, characteristics of the long-term landfill settlement are analysed and the starting date of residual settlement is deduced using the data of the landfill 1 of the Gimpo Metropolitan Landfill (GML) measured for 27 years. The landfill 1 is a multi-staged municipal solid waste landfill where dykes are constructed after landfilling for subsequent waste fills. The landfilling began in 1992 and finished in 2000, and the waste settlement measurement continued throughout this period. The older waste of the lower lift shows higher biodegradation and larger settlement than the waste of the upper lift, which acts as vertical load. Large settlement occurred in the lower lifts due to the collapse of waste voids caused by the overburden load of the upper lifts after biodegradation of waste in the lower lifts during long-term landfilling. In the conventional landfills, that is, mono-layer landfills, the time-dependent settlement generally occurs after the stress-dependent settlement. But, most of the time, this landfill showed mainly the time-dependent settlement. The duration, at which the biodegradation of organic matters is reduced and the residual settlement begins, was 8.8 years in average and the date range was from 7.6 to 11.7 years considering each disposed block in landfill 1. This date is obtained by calculating from the mid-point time of the landfilling duration.

Excess endocrine growth hormone in acromegaly promotes the aggressiveness and metastasis of triple-negative breast cancer.

Pituitary adenoma-induced excess endocrine growth hormone (GH) secretion can lead to breast cancer development and metastasis. Herein, we used an acromegaly mouse model to investigate the role of excess endocrine GH on triple-negative breast cancer (TNBC) growth and metastasis. Additionally, we aimed to elucidate the molecular mechanism of transcription factor 20 (TCF20)/nuclear factor erythroid 2-related factor 2 (NRF2) signaling-mediated aggressiveness and metastasis of TNBC. Excess endocrine GH induced TCF20 activates the transcription of NRF2 and NRF2-target genes to facilitate TNBC metastasis. Inhibition of GH receptor (GHR) and TCF20 activity using the GHR antagonist or small-interfering RNA-induced gene knockdown resulted in reduced tumor volume and metastasis, suggesting that excess endocrine GH stimulates TCF20/NRF2 pathways in TNBC and promotes metastasis to the lung. GHR inhibitors present an effective therapeutic strategy to prevent TNBC cell growth and metastasis. Our findings revealed functional and mechanistic roles of the GH-TCF20-NRF2 signaling axis in TBNC progression.

Comparison of waste settlement characteristics for two landfills disposed in long sequential periods.

Changes in waste management policy affect the settlement characteristics of waste landfills in which the waste disposal is operated for decades. In this study, the waste settlements were calculated by using the data measured in two multi-staged landfills for 27 years. The relationship between the changes in waste management policies and settlement characteristics is analyzed. Sequentially launched waste management policies reduced the organic matters in municipal solid waste (MSW) of the landfill. This change in turn influenced the engineering properties of landfill waste, e.g. water content, unit weight, and initial void ratio, etc. Due to the reduction of food waste in landfills, the water content decreased and the unit weight increased. The initial void ratio declined by the decrease of water content and the increase of unit weight. The annual primary and secondary compression indices, Cc and Cα, of each lift also increased/decreased due to the change in waste composition. The Cc of Phase #1 increased from an average of 0.34 to an average of 0.51 because the percentage of coal ash in MSW drastically decreased and the percentage of food, paper, and plastic, which are highly compressible, increased. On the other hand, the Cc of Phase #2 declined from an average of 0.15 to an average of 0.025 due to the decrease of the waste compressibility from the reduction of organic matters. The Cα of Phase #1 and #2 decreased by the reduction of organic matter and moisture which are needed for biodegradation of wastes in the landfill.

Efficacy of Immunohistochemistry for SDHB in the Screening of Hereditary Pheochromocytoma-Paraganglioma.

The most common genetic backgrounds of hereditary paraganglioma and pheochromocytoma (PPGL) are SDHx germline mutations. Given the fact that the immunohistochemistry (IHC) result for SDHB is always negative regardless of the type of SDHx mutation, we aimed to evaluate the efficacy of using SDHB IHC for screening SDHx mutations in PPGL cases. In total, 52 patients who underwent surgery for PPGL treatment between 2006 and 2020 and underwent genetic analysis at diagnosis were included. Tissue microarrays (TMAs) were constructed with PPGL tissues and IHC for SDHB was performed on TMA sections. All 10 patients with SDHB-negative IHC contained SDHB or SDHD mutations. The genetic test results of patients with SDHB-weakly positive IHC varied (one SDHB, two RET, one VHL, and three unknown gene mutations). There were no SDHx mutations in the SDHB-positive IHC group. Six patients with weakly positive SDHB IHC with primarily unknown genetic status were re-called and underwent next-generation sequencing. None of them had SDHx mutations. In conclusion, SDHB-negative IHC is a cost-effective and reliable method to predict SDHx mutations. However, in the case of weakly positive SDHB staining, an additional gene study should be considered.

The effect of direct communication between emergency physicians and interventional cardiologists on door to balloon times in STEMI.

We developed an institutional protocol mandating emergency physicians to contact the interventional cardiologist directly in all cases of ST-segment elevation myocardial infarction (STEMI) and hypothesized that this would reduce door-to-balloon-times (DTBT). From January 2004 to July 2006, 208 patients with STEMI were treated with primary percutaneous coronary intervention (PCI). A total of 144 patients were treated before implementing the new protocol ("before") and 64 patients were treated after the implementation ("after"). The DTBT was significantly reduced from 148+/-101 min to 108+/-56 min (p<0.05). While only 25% of the "before'' patients received PCI within 90 min after arrival, 50% of the "after'' patients received PCI within 90 min (p<0.05). There were no significant differences between two groups in other outcomes (postprocedural TIMI flow, mortality, subsequent stroke, heart failure, shock, reinfarction, length of stay in intensive care unit, and the total hospital length of stay). In conclusion, mandating emergency physicians to directly notify interventional cardiologists of all STEMI patients reduces DTBT.