Quality Assurance for Caltrans Bridge Shear Retrofit Projects

A quality assurance (QA) process is proposed to prevent the possibility of legal issues for a multibridge retrofit project recently conducted by the California Department of Transportation (Caltrans) to increase the horizontal shear resistance of decks. Providing a solution requires determining an appropriate number of samples with the corresponding sampling scheme to ensure 95% compliance with the specification requirements. The determination of the appropriate sample size must recognize the practical considerations of cost, time, statistical simulation results, and the binomial distribution theory. It is not uncommon for many agencies to base quality assurance on just three samples. Using a binomial distribution, a discussion is also presented why it is not appropriate to take this limited number of samples for quality assurance. With the selection of sample size for each bridge, a representative sampling scheme that is random and unbiased was developed using the concept of uniform design as sampling strategy. The recommended acceptance criteria are specified based on the hypothesis testing results with the normal approximation of a binomial distribution

Warm-Mix Asphalt Study: Test Track Construction and FirstLevel Analysis of Phase 3b HVS and Laboratory Testing (Rubberized Asphalt, Mix Design #2)

This is one of two reports describing the third phase of a warm-mix asphalt study that compares the performance of two rubberized asphalt control mixes with that of seven mixes produced with warm-mix technologies. The control mixes were produced and compacted at conventional hot-mix asphalt temperatures (>300 F [150°C]), while the warm-mixes were produced and compacted at temperatures between 36°F (20°C) and 60°F (35°C) lower than the controls. The mixes, test track, Heavy Vehicle Simulator (HVS) and laboratory testing are discussed. Key findings from the study include: Adequate compaction can be achieved on rubberized warm-mixes at lower temperatures. Optimal compaction temperatures will differ. Equal and potentially better rutting performance can be achieved provided that standard specified limits for hot-mix asphalt are met. Test results indicate that use of the warm-mix technologies did not significantly influence performance when compared to control specimens. However, the mixes produced with chemical surfactant technologies did appear to be influenced in part by the lower mix production and construction temperatures, which would have resulted in less oxidation of the binder and consequent lower stiffness of the mix. Rutting performance, fatigue performance and moisture sensitivity did not appear to be affected. The warm-mixes produced using water-foaming technologies appeared to have lower moisture resistance compared to the other warm-mixes. Smoke and odors are significantly reduced on warm-mixes compared to hot-mixes, while workability is considerably better on warm-mixes compared to hot-mixes. The HVS and laboratory testing completed in this phase have provided no results to suggest that warm-mix technologies should not be used in rubberized asphalt in California

Teaching topographic map skills and geomorphology concepts with Google Earth in a one-computer classroom

Teaching high-school geomorphological concepts and topographic map reading entails many challenges. This research reports the applicability and effectiveness of Google Earth in teaching topographic map skills and geomorphological concepts, by a single teacher, in a one-computer classroom. Compared to learning via a conventional instructional method, students learning with Google Earth do not have different geomorphological concepts development because both settings enable students to learn with similar static representation. However, students learning with Google Earth improve topographic map skills significantly compared to the conventional instructional method. This is because of the 3D landscape visualization and prior knowledge connections available with Google Earth

Attenuated Cardiac Mitochondrial-Dependent Apoptotic Effects by Li-Fu Formula in Hamsters Fed with a Hypercholesterol Diet

Apoptosis involves in the pathogenesis of various cardiac abnormalities. This study intends to evaluate the effects of Li-Fu formula on cardiac apoptosis induced by hyper-cholesterol diet. Twenty-four male Golden Syrian hamsters were randomly divided into Control, Cholesterol and Li-Fu formula groups. Histopathological analysis, western blotting and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assays were performed to measure the effects of Li-Fu formula on left ventricle. Significantly reduced TUNEL-positive cells and mitochondria- dependent apoptosis were observed in the left ventricle of hamsters from Li-Fu formula group compared to the Cholesterol group. Additionally, induced cardiac insulin like growth factor I receptor (IGFIR)-dependent survival pathway was detected in the Li-Fu formula group compared to the Cholesterol group. Besides, minor fibrosis, increased collagen deposition, and myofibril disarray was detected in the Cholesterol group, whereas the reductions of collagen deposition and myofibril disarray were observed in the Li-Fu formula group. This study demonstrated that Li-Fu formula not only reduced the mitochondria-dependent apoptosis and fibrosis, but also enhanced the IGF-I survival pathway in the left ventricle from high cholesterol-fed hamsters. We suggest the protective effects of Li-Fu formula on cardiac apoptosis and therapeutic potentials against cardiovascular disease

Ameliorate Effects of Li-Fu Formula on IL-6-Mediated Cardiac Hypertrophy in Hamsters Fed with a Hyper-Cholesterol Diet

Hypercholesterolemia diets are considered as major sources to cause cardiac hypertrophy. This study intends to evaluate the effects of Li-Fu formula on cardiac hypertrophy induced by hypercholesterolemia diet. Twenty-four male Golden Syrian hamsters were randomly divided into control, cholesterol and Li-Fu formula groups and fed with different experimental diets for 2 months. Histopathological analysis and western blotting were performed to measure the myocardial architecture, and various cardiac hypertrophy-associated molecules in the excised left ventricle from hamsters. The ratios of whole heart weight/body weight (BW) and left ventricle weight/BW were significantly higher in the cholesterol group but significantly lower in the Li-Fu formula group. The protein levels of both atrial natriuretic peptide and brain natriuretic peptide were significantly increased in the cholesterol group but significantly reduced in the Li-Fu formula group. Additionally, significantly increased interleukin-6, STAT3, MEK5, p-ERK5 and non-cardiomyocyte proliferate signal molecules such as p-MEK and p-ERK, were detected in the cholesterol group but significantly reduced in the Li-Fu formula group. Notably, no significant variations of inflammatory signaling molecules, including p-P38 and p-JNK, were detected in all groups. Our experimental results demonstrated the significant reductions of cardiac hypertrophy and related eccentric hypertrophy signaling, non-cardiomyocyte proliferate signaling in the excised left ventricle of hamsters from the Li-Fu formula. We suggested the protective effects of Li-Fu formula on cardiac hypertrophy that may be useful in prevention or treatment of hypertrophy-associated cardiovascular diseases

Garlic Oil Alleviates MAPKs- and IL-6-mediated Diabetes-related Cardiac Hypertrophy in STZ-induced DM Rats

Garlic oil has been reported to protect the cardiovascular system; however, the effects and mechanisms behind the cardioprotection of garlic oil on diabetes-induced cardiaomyopathy are unclear. In this study, we used streptozotocin (STZ)-induced diabetic rats to investigate whether garlic oil could protect the heart from diabetes-induced cardiomyopathy. Wistar STZ-induced diabetic rats received garlic oil (0, 10, 50 or 100 mg kg_1 body weight) by gastric gavage every 2 days for 16 days. Normal rats without diabetes were used as control. Cardiac contractile dysfunction and cardiac pathologic hypertrophy responses were observed in diabetic rat hearts. Cardiac function was examined using echocardiography. In addition to cardiac hypertrophy-related mitogen-activated protein kinases (MAPK) pathways (e.g., p38, c-Jun N-terminal kinases (JNK) and extracellularly responsive kinase (ERK1/2)), the IL-6/MEK5/ERK5 signaling pathway was greatly activated in the diabetic rat hearts, which contributes to the up-regulation of cardiac pathologic hypertrophy markers including atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP), and leads to cardiac contractile dysfunction. Garlic oil treatment significantly inhibited the up-regulation in MAPK (e.g., p38, JNK and ERK1/2) and IL-6/MEK5/ERK5 signaling pathways in the diabetic rat hearts, reducing the levels of cardiac pathologic hypertrophy markers such as ANP and BNP, and improving the cardiac contractile function. Collectively, data from these studies demonstrate that garlic oil shows the potential cardioprotective effects for protecting heart from diabetic cardiomyopathy

Advantage of laparoscopic surgery in patients with generalized obesity operated for colorectal malignancy: A retrospective cohort study

BackgroundBecause of the progression of minimally invasive surgery skills and obesity in colorectal surgery, we aimed to evaluate the short-term outcomes of colorectal cancer resections in patients with generalized obesity at a single teaching hospital with mature surgical techniques and training programs.MethodsA total of 537 patients were diagnosed with CRC and had a body mass index ≥30 kg/m2 between January 2009 and December 2019 at a single institution. 265 patients underwent open surgery and 272 patients underwent laparoscopic surgery. Data were analysed to explore the independent risk factors for postoperative complications.ResultsThe laparoscopic group had less blood loss (73 ± 128 vs. 148 ± 290 ml, p < 0.001) and a shorter postoperative hospital stay (10.8 ± 17.1 vs. 11.7 ± 6.8 days, p < 0.001) than the open group. The number of harvested lymph nodes did not significantly differ between the two groups (30.9 ± 18.3 vs. 30.2 ± 15.3, p = 0.981). Although anastomotic leakage was significantly higher in the laparoscopic group (1.5% vs. 4.8%, p = 0.030), there were also similar overall postoperative morbidity and mortality rates between the open and laparoscopic groups for CRC patients with generalized obesity who underwent surgery.ConclusionLaparoscopic surgery can reduce blood loss, decrease the length of hospital stay, obtain a similar number of harvested lymph nodes, and achieve an acceptable conversion rate for CRC patients with generalized obesity. We suggest that laparoscopic surgery could become a standard method for CRC treatment in patients with generalized obesity