THERMAL PERFORMANCE EVALUATION AND ANALYSIS OF THE EFFICIENT and SUSTAINABILITY SHELL AND TUBE HEAT EXCHANGER SYSTEM

Shell and tube heat exchanger (STHE) is one of the most attractive heat exchanger types and widely used in many industrial processes, power generation, and chemical process industries because of the STHE suits the high-pressure applications and harsh environment. STHE porotype consists of a shell with a bundle of tubes and several baffles inside it. The objective of the study is to model and analysis of thermal performance and heat transfer in the advanced STHE system by using ANSYS Fluent along with the experiment. The advanced computational simulation tool, ANSYS Fluent, and AutoCAD were used to model the STHE system along with the one shell (8” diameter), five tubes (1” diameter) and four baffles. In this study, steel was selected for shell materials, copper and brass was compared to select better performance materials for tubes. The constructed STHE model has meshed and analyzed under two mediums (water and biogas) with different thermal conditions. Besides, the experiment results from the STHE prototype were used to investigate conversion efficiency and analyze heat transfer. The analysis of variance (ANOVA) method was used to analyze the significant effect of hot water flow rate and inlet temperature on heat transfer of the STHE prototype. Results from simulation and Karen’s method indicated the heat release of the brass is lower than the copper in the system. Under various operating conditions, experimental results showed the conversion efficiency of the lab-scale STHE is a high range of 0.80-0.86. In addition, ANOVA results indicated that the hot water inlet temperature has a significant effect on heat transfer of STHE prototype

EVALUATION AND ANALYSIS OF THE SUSTAINABLE WASTE-TO-ENERGY SYSTEM PERFORMANCE FOR THE POULTRY FARM

Poultry litter is one type of biomass and waste generated from the poultry farms. However, excess land application of poultry litter caused eutrophication problems of surface waters coming from the watershed and destroyed the aquatic ecology. Co-combustion of poultry litter and coal were widely studied in fluidized bed combustor as an alternative disposal method during last two decades. However, there are severe environmental problems (i.e., gaseous emissions) and public health impact associated with the poultry litter and coal co-combustion process. In this study, poultry litter and natural gas co-combustion was investigated in the lab-scale waste-to-energy system to provide a sustainable and cost-effective disposal route for poultry farms. This waste-to-energy system integrates the Stirling Engine (SE), Shell-Tube Heat Exchanger (STHE) and the lab-scale Swirling Fluidized Bed Combustor (SFBC) with other systems (e.g., cyclone, air supply system, fuel feeding system). Measures of heat transfer effect, electricity output and gas emissions levels were used to evaluate the lab-scale waste-to-energy system performance. Results indicated that lab-scale waste-to-energy system can produce electricity (close to 1 kW) and hot water (57.2°C) while reducing NOx and SO2 emissions during the poultry litter and natural gas co-combustion process. In addition, energy flow analysis indicated that SE and STHE system might use 14.7% and 21.0% of total energy input in fuels, respectively, to generate useful energy.  In addition, a sustainable life cycle of poultry litter was built and suggested to process poultry wastes in the poultry farms

DESIGN, FABRICATION AND TESTING OF A LAB-SCALE HYBRID MOBILE COOLING SYSTEM FOR OYSTER INDUSTRY

Cooling system is critical to maintain freshness of oysters and avoid contamination by bacteria. However, there is no persistent and efficient temperature control mechanism for cooling and storing of oysters in its supply chain from oyster farmer to the end consumers (e.g., market, restaurants). The aim of this project is to design, fabricate, and evaluate a lab-scale hybrid mobile cooling system for oyster aquaculture. This innovative hybrid cooling system integrated 110 volts AC cooling unit and 12 volts DC cooling unit with six individual chambers. These special features it to work under different power source. Even after power off, it can still run for several hours with battery (i.e., outage). So, it can be moved from boat to customers without change the storage condition of oysters. Six individual chambers have a potential to reduce energy loss and improve cooling performance because removing oyster baskets from one chamber will not affect temperatures in the other chambers. In this study, cooling system was fabricated in the laboratory based on the 2D design and 3D model. The performance of this cooling system was tested under various air circulation conditions (e.g., no vent open, two vents open, two vents open and air circulation fan on). Both cooling speed and the stand deviation of chamber temperature were used to evaluate the system cooling performance. Results indicated that the additional of air fan and two open vents in the divider has better cooling performance than the other two operating conditions. Hybrid cooling system with two vents and air circulation fan on can effectively cool down the oyster temperature from 21.1 º C to 5.6 º C within three hours. The stand deviation of the temperatures in six individual chambers can be reduced to 0.83 º C in four hours

COMPARATIVE STUDY OF A SUSTAINABLE HYBRID HEATING SYSTEM IN A GREEN INFRASTRUCTURAL BUILDING

Traditional energy production from fossil fuel conversion process creates negative environmental impact and affects human health. Thus, the usage of solar space heating piques the interest of several countries and organizations because it can reduce fossil energy consumption and is environmentally friendly. This paper conducted a comparative study between the advantages and impacts of using a sustainable Hybrid Heating System (HHS) and a Conventional Heating System (CHS) in an infrastructural building. The Centre for the Built Environment and Infrastructure Studies (CBEIS), a GOLD LEED-certified building of Morgan State University (MSU) is currently using an HHS for heating and cooling of electricity production. Several testing and analysis were used to compare and evaluate the performance and advantages of the HHS. The results showed that HHS has a significant edge over the CHS and was able to reduce the annual cost of the electric bill for almost $25,000. The statistical results and Analysis of Variance (ANOVA) confirmed that there was a significant difference during the months of winter and summer season in determining how much Kilowatt (kW) produced during the process

The Myxoma Poxvirus Protein, M11L, Prevents Apoptosis by Direct Interaction with the Mitochondrial Permeability Transition Pore

M11L, an antiapoptotic protein essential for the virulence of the myxoma poxvirus, is targeted to mitochondria and prevents the loss of mitochondrial membrane potential that accompanies cell death. In this study we show, using a cross-linking approach, that M11L physically associates with the mitochondrial peripheral benzodiazepine receptor (PBR) component of the permeability transition (PT) pore. Close association of M11L and the PBR is also indicated by fluorescence resonance energy transfer (FRET) analysis. Stable expression of M11L prevents the release of mitochondrial cytochrome c induced by staurosporine or protoporphyrin IX (PPIX), a ligand of the PBR. Transiently expressed M11L also prevents mitochondrial membrane potential loss induced by PPIX, or induced by staurosporine in combination with PK11195, another ligand of the PBR. Myxoma virus infection and the associated expression of early proteins, including M11L, protects cells from staurosporine- and Fas-mediated mitochondrial membrane potential loss and this effect is augmented by the presence of PBR. We conclude that M11L regulates the mitochondrial permeability transition pore complex, most likely by direct modulation of the PBR

Cryptopleurine Targets NF-κB Pathway, Leading to Inhibition of Gene Products Associated with Cell Survival, Proliferation, Invasion, and Angiogenesis

Cryptopleurine, a phenanthroquinolizidine alkaloid, was known to exhibit anticancer activity; however, the underlying mechanism is poorly understood. Because the nuclear factor-κB (NF-κB) transcription factors control many physiological processes including inflammation, immunity, and development and progression of cancer, we investigated the effects of cryptopleurine on tumor necrosis factor alpha (TNF-α)-induced NF-κB activation pathway and on the expression of NF-κB-regulated gene products associated with many pathophysiological processes.MDA-MB231, MDA-MB435, MCF-7, HEK293, RAW264.7 and Hep3B cells were used to examine cryptopleurine's effect on the NF-κB activation pathway. Major assays were promoter-reporter gene assay, electrophoretic mobility shift assay (EMSA), in vitro immune complex kinase assay, real-time PCR, Western blot analysis, and Matrigel invasion assay. Experiments documenting cell proliferation and apoptosis were analyzed by MTT method and flow cytometry, respectively. The results indicated that cryptopleurine suppressed the NF-κB activation through the inhibition of IκB kinase (IKK) activation, thereby blocking the phosphorylation and degradation of the inhibitor of NF-κB alpha (IκBα) and the nuclear translocation and DNA-binding activity of p65. The suppression of NF-κB by cryptopleurine led to the down-regulation of gene products involved in inflammation, cell survival, proliferation, invasion, and angiogenesis.Our results show that cryptopleurine inhibited NF-κB activation pathway, which leads to inhibition of inflammation, proliferation, and invasion, as well as potentiation of apoptosis. Our findings provide a new insight into the molecular mechanisms and a potential application of cryptopleurine for inflammatory diseases as well as certain cancers associated with abnormal NF-κB activation

Sliding motion of a two-dimensional Wigner crystal in a strong magnetic field

We study the sliding state of a two-dimensional Wigner crystal in a strong magnetic field and a random impurity potential. Using a high-velocity perturbation theory, we compute the nonlinear conductivity, various correlation functions, and the interference effects arising in combined AC + DC electric effects, including the Shapiro anomaly and the linear response to an AC field. Disorder is found to induce mainly transverse distortions in the sliding state of the lattice. The Hall resistivity retains its classical value. We find that, within the large velocity perturbation theory, free carriers which affect the longitudinal phonon modes of the Wigner crystal do not change the form of the nonlinear conductivity. We compare the present sliding Wigner crystal in a strong magnetic field to the conventional sliding charge-density wave systems. Our result for the nonlinear conductivity agrees well with the $I-V$ characteristics measured in some experiments at low temperatures or large depinning fields, for the insulating phases near filling factor $\nu$ = 1/5. We summarize the available experimental data, and point out the differences among them.Comment: appeared in RPB vol. 50, 4600 (1994); LaTex file; 3 figures available from [email protected]

An Active Learning Approach for Rapid Characterization of Endothelial Cells in Human Tumors

Currently, no available pathological or molecular measures of tumor angiogenesis predict response to antiangiogenic therapies used in clinical practice. Recognizing that tumor endothelial cells (EC) and EC activation and survival signaling are the direct targets of these therapies, we sought to develop an automated platform for quantifying activity of critical signaling pathways and other biological events in EC of patient tumors by histopathology. Computer image analysis of EC in highly heterogeneous human tumors by a statistical classifier trained using examples selected by human experts performed poorly due to subjectivity and selection bias. We hypothesized that the analysis can be optimized by a more active process to aid experts in identifying informative training examples. To test this hypothesis, we incorporated a novel active learning (AL) algorithm into FARSIGHT image analysis software that aids the expert by seeking out informative examples for the operator to label. The resulting FARSIGHT-AL system identified EC with specificity and sensitivity consistently greater than 0.9 and outperformed traditional supervised classification algorithms. The system modeled individual operator preferences and generated reproducible results. Using the results of EC classification, we also quantified proliferation (Ki67) and activity in important signal transduction pathways (MAP kinase, STAT3) in immunostained human clear cell renal cell carcinoma and other tumors. FARSIGHT-AL enables characterization of EC in conventionally preserved human tumors in a more automated process suitable for testing and validating in clinical trials. The results of our study support a unique opportunity for quantifying angiogenesis in a manner that can now be tested for its ability to identify novel predictive and response biomarkers

BMP-2 Up-Regulates PTEN Expression and Induces Apoptosis of Pulmonary Artery Smooth Muscle Cells under Hypoxia

To investigate the role of bone morphogenetic protein 2 (BMP-2) in regulation of phosphatase and tensin homologue deleted on chromosome ten (PTEN) and apoptosis of pulmonary artery smooth muscle cells (PASMCs) under hypoxia.Normal human PASMCs were cultured in growth medium (GM) and treated with BMP-2 from 5-80 ng/ml under hypoxia (5% CO(2)+94% N(2)+1% O(2)) for 72 hours. Gene expression of PTEN, AKT-1 and AKT-2 were determined by quantitative RT-PCR (QRT-PCR). Protein expression levels of PTEN, AKT and phosph-AKT (pAKT) were determined. Apoptosis of PASMCs were determined by measuring activities of caspases-3, -8 and -9. siRNA-smad-4, bpV(HOpic) (PTEN inhibitor) and GW9662 (PPARγ antagonist) were used to determine the signalling pathways.Proliferation of PASMCs showed dose dependence of BMP-2, the lowest proliferation rate was achieved at 60 ng/ml concentration under hypoxia (82.2±2.8%). BMP-2 increased PTEN gene expression level, while AKT-1 and AKT-2 did not change. Consistently, the PTEN protein expression also showed dose dependence of BMP-2. AKT activity significantly reduced in BMP-2 treated PASMCs. Increased activities of caspase-3, -8 and -9 of PASMCs were found after cultured with BMP-2. PTEN expression remained unchanged when Smad-4 expression was inhibited by siRNA-Smad-4. bpV(HOpic) and GW9662 (PPARγ inhibitor) inhibited PTEN protein expression and recovered PASMCs proliferation rate.BMP-2 increased PTEN expression under hypoxia in a dose dependent pattern. BMP-2 reduced AKT activity and increased caspase activity of PASMCs under hypoxia. The increased PTEN expression may be mediated through PPARγ signalling pathway, instead of BMP/Smad signalling pathway