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Managing woody biomass transportation for improved biomass economics
With rising fuel costs and enhanced environmental concerns, the use of renewable energy has been steadily considered and widely expounded as a solution to the challenges of global energy security and climate change. The use of woody biomass, in particular, has received considerable attention for energy production due to the potential availability of large volumes from fuel reduction thinning operations and healthy forest restoration plans. However, woody biomass utilization is not as economically attractive as fossil fuel due to the high production and transportation costs compared to the relatively low market values of these materials. Therefore, identifying or developing cost effective production and transportation systems has become an economically critical issue to expand biomass utilization. In woody biomass production, the transportation of wood raw materials from the sources to the conversion facilities is the largest single component of production costs for many suppliers around the world. Therefore, small increases in transportation efficiency could significantly reduce the overall production costs. The purpose of this study was to provide new knowledge which leads to improvements in the economic feasibility of using woody biomass for energy through reductions in transportation costs.
This dissertation:
• Developed prediction models to estimate the travel times including terminal (loading and unloading) times to haul woody biomass from non-forest sources to conversion facilities in western Oregon and determined the effects of off-forest road classes on transportation times and costs. The travel time prediction model developed was shown to be a good predictor for travel time through a validation procedure. The average percent difference between actual and predicted travel times was only 6 percent.
• Developed a computer model, named BIOTRANS, to estimate the biomass transportation productivity and cost and evaluated the effects on transportation costs of different truck configurations, transported material types, and travel route characteristics. Different truck configurations and transported material types significantly affected transportation costs. A 4 axle truck and single trailer was the most cost efficient hauling configuration for the conditions studied and shavings have 30 percent higher trucking costs than other material types.
• Developed an optimization model to solve a truck scheduling problem for transporting four types of woody biomass in western Oregon. For an actual 50-load order size, the truck scheduling model produced significant improvements in solution values within 18 seconds. The average reductions in transportation cost and total travel time were 18% and 15%, respectively.
• Reviewed collaborative management systems and described the potential implementation of collaborative transportation management in the woody biomass transportation industry.Keywords: Transportation costs, Truck scheduling, Collaborative transportation, Road classification system, Woody biomass, Prediction model
Comparison of total body irradiation-based or non-total body irradiation-based conditioning regimens for allogeneic stem cell transplantation in pediatric leukemia patients
Purpose : This study aims to compare the outcome of total body irradiation (TBI)- or non-TBI-containing conditioning regimens for leukemia in children. Methods : We retrospectively evaluated 77 children conditioned with TBI (n=40) or non-TBI (n=37) regimens, transplanted at Chonnam National University Hospital between January 1996 and December 2007. The type of transplantation, disease status at the time of transplant, conditioning regimen, engraftment kinetics, development of graft-versus-host disease (GVHD), complications, cause of deaths, overall survival (OS), and event-free survival (EFS) were compared between the 2 groups. Results : Among 34 patients with acute lymphoblastic leukemia (ALL), 28 (82.4%) were in the TBI group, while 72.7% (24/33) of patients with myeloid leukemia were in the non-TBI group. Although the 5-year EFS of the 2 groups was similar for all patients (62% vs 63%), the TBI group showed a better 5-year EFS than the non-TBI group when only ALL patients were analyzed (65% vs 17%; P =0.005). In acute myelogenous leukemia patients, the non-TBI group had better survival tendency (73% vs 38%; P=0.089). The incidence of GVHD, engraftment, survival, cause of death, and late complications was not different between the 2 groups. Conclusion : The TBI and non-TBI groups showed comparable results, but the TBI group showed a significantly higher 5-year EFS than the non-TBI group in ALL patients. Further prospective, randomized controlled studies involving larger number of patients are needed to assess the late-onset complications and to compare the socioeconomic quality of life
Validating of the pre-clinical mouse model for metastatic breast cancer to the mandible
Metastatic breast carcinoma has a great tendency to spread to the mandible. It is concomitantly associated with bone destruction, food intake disorder, and a poorer prognosis. Appropriate animal models need to be developed for a better understanding of the mechanisms underlying the metastatic process of breast cancer cells to mandible and to test the effects of potential lead compounds. Here, we assessed the metastasis model of intracardiac injection using luciferase-transfected metastatic breast cancer cells (MDA-MB-231Luc+) by determining the incidences of metastasis, mCT images, and histopathological results. A high bioluminescence signal mainly detected mandibular lesions with less frequent distal femora and proximal tibiae lesions. Extensive mandibular bone destruction occurred in nude mice grafted with metastatic breast cancer cells. This type of animal model might be a useful tool in assessing therapeutic implications and the efficacy of anti-cancer drugs for osteolytic cancers
Collagen Immobilization on Ultra-thin Nanofiber Membrane to Promote In Vitro Endothelial Monolayer Formation
The endothelialization on the poly (epsilon-caprolactone) nanofiber has been limited due to its low hydrophilicity. The aim of this study was to immobilize collagen on an ultra-thin poly (epsilon-caprolactone) nanofiber membrane without altering the nanofiber structure and maintaining the endothelial cell homeostasis on it. We immobilized collagen on the poly (epsilon-caprolactone) nanofiber using hydrolysis by NaOH treatment and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/sulfo-N-hydroxysulfosuccinimide reaction as a cost-effective and stable approach. NaOH was first applied to render the poly (epsilon-caprolactone) nanofiber hydrophilic. Subsequently, collagen was immobilized on the surface of the poly (epsilon-caprolactone) nanofibers using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide/sulfo-N-hydroxysulfosuccinimide. Scanning electron microscopy, Fourier transform infrared spectroscopy, transmission electron microscopy, and fluorescence microscopy were used to verify stable collagen immobilization on the surface of the poly (epsilon-caprolactone) nanofibers and the maintenance of the original structure of poly (epsilon-caprolactone) nanofibers. Furthermore, human endothelial cells were cultured on the collagen-immobilized poly (epsilon-caprolactone) nanofiber membrane and expressed tight junction proteins with the increase in transendothelial electrical resistance, which demonstrated the maintenance of the endothelial cell homeostasis on the collagen-immobilized-poly (epsilon-caprolactone) nanofiber membrane. Thus, we expected that this process would be promising for maintaining cell homeostasis on the ultra-thin poly (epsilon-caprolactone) nanofiber scaffolds.11Ysciescopu
Two Cases of Giant Epidermal Cyst Occurring in the Neck
Epidermal cysts are the most common cysts of the skin. Aconventional epidermal cyst rarely reaches a size of more than 5 cm in diameter. We report on two cases of giant epidermal cyst occurring in the neck. One patient had a cyst measuring 12×9×9 cm and the other patient had a non-pulsatile, dome-shaped lesion in the neck, which measured 6×5×3 cm. The lesions were totally excised. Histopathologically, both were confirmed as giant epidermal cysts
Chylothorax in Gorham's disease.
A 25-yr-old woman presented with a right pleural effusion. Destruction of 9th through 12th ribs, adjacent vertebral bodies, and transverse processes was noted on plain radiograph and a large low-attenuated, irregular shaped mass lesion with peripheral rim enhancement, destroying vertebral body and transverse process, was revealed on the computed tomographic scan. Magnetic resonance imaging showed high signal on T1- weighted image and iso- and low signal on T2-weighted image for the mass lesion replacing the vertebral bony cortex and marrow space. An open rib biopsy revealed the histopathological changes of Gorham's disease (essential osteolysis), even though only bloody fluid filling the empty space and rib and vertebral transverse process destruction were grossly observed on operation. Even though there was no definite response to radiotherapy and pleurodesis, the patient showed stable condition up to 20 months after diagnosis
Bilateral Traumatic Anterior Dislocation of the Hip with an Unstable Lumbar Burst Fracture
Traumatic anterior dislocation of the hip is rare. Bilateral traumatic anterior dislocation is an even rarer injury; indeed, only 5 cases have been reported in the English literature. We describe a case of a bilateral traumatic anterior dislocation of the hip and a concomitant unstable lumbar burst fracture following a mechanism of injury distinctly different from other reports
Spontaneous HBsAg loss in Korean patients: relevance of viral genotypes, S gene mutations, and covalently closed circular DNA copy numbers
Background/AimsOccult HBV infection can persist following HBsAg loss and be transmitted, but the virological features are not well defined.MethodsHere we investigated 25 Korean patients who lost HBsAg during follow up, either spontaneously or subsequent to therapy.ResultsWhereas subtype adr (genotype C) was found in 96% of HBsAg positive patients, 75 % of patients who lost HBsAg spontaneously were seemed to be infected with the ayw subtype with sequence similar to genotype D. Mutations in the major hydrophilic region (MHR) of HBsAg were found in 7 patients who lost HBsAg spontaneously. The mutations include T123S, M125I/N, C139R, D144E, V177A, L192F, and W196L, some of which have not been reported before. Functional analysis via transfection experiments indicate that the C139R and D144E mutations drastically reduced HBsAg antigenicity, while the Y225del mutation found in one interferon-treated patient impaired HBsAg secretion.ConclusionsLack of detectable HBsAg in patient serum could be explained by low level of ccc DNA in liver tissue, low antigenicity of the surface protein, or its secretion defect
Randomized Comparison of Four-Times-Daily versus Once-Daily Intravenous Busulfan in Conditioning Therapy for Hematopoietic Cell Transplantation
AbstractSixty patients were randomized to receive intravenous busulfan (iBU) either as 0.8 mg/kg, over 2 hours 4 times a day (BU4 arm) or 3.2 mg/kg, over 3 hours once a day (BU1 arm) in conditioning therapy for hematopoietic cell transplantation. The complete pharmacokinetic parameters for the first busulfan dose were obtained from all patients and were comparable between the 2 arms: for the BU4 and BU1 groups, elimination half-life (mean ± SD) was 2.75 ± 0.22 versus 2.83 ± 0.21 hours, estimated daily AUC was 6058.0 ± 1091.9 versus 6475.5 ± 1099.4 μM·min per day, and clearance was 2.05 ± 0.36 versus 1.91 ± 0.31 mL/min/kg, respectively. Times to engraftment after transplantation were similar between the 2 arms. No significant differences were evident in the occurrence of acute graft-versus-host disease (aGVHD) and hepatic veno-occlusion disease (VOD). Moreover, other toxicities observed within 100 days after transplantation were not significantly different between the 2 arms. The cumulative incidence of nonrelapse mortality was 20.8% in BU4 arm and 13.3% in BU1 arm. In conclusion, our randomized study demonstrates that the pharmacokinetic profiles and posttransplant complications are similar for once-daily iBU and traditional 4-times-daily iBU
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