Modeling, Simulation, and Automatic Control for Optimum Drying and Storage of Rough Rice in a Bin System.

A study on modeling, simulation, and automatic control for optimum drying and storage of rough rice in a farm-bin system was conducted to address some aspects of rice post-harvest technology. Resistance-type moisture sensors and temperature and humidity sensors were evaluated for continuously monitoring the conditions of air and grain. Models to predict rice moisture models during drying and storage were developed. Based on accuracy and predictability, the use of the capacitance-type humidity sensor is recommended over the resistance-type moisture sensor. A pressure drop model of airflow through rough rice was developed to aid in determining the optimum size and type of fan for aeration. The effect of rice moisture on the pressure drop was statistically significant at the 5% level. A respiration model for rough rice was developed to predict the carbon dioxide produced during storage and to determine the dry matter loss of the stored rice. The effects of gas modulating control and air recirculation on the energy savings in a bin-drying system of rough rice were analyzed by a computer simulation using SLAM II/PC. The gas modulating system saved 25% of total energy in August, and 8% in December, while the effect of air recirculation without dehumidification was negative in saving energy. Air recirculation with dehumidification saved much more drying energy in December as the air recirculation ratio increased, but the air recirculation was never necessary during August due to high drying potential in southwest Louisiana. The control criteria for an automatic aeration system of rough rice based on the temperature of air and grain, relative humidity of air, rice moisture, deterioration index, and dry matter loss were determined. This aeration control criteria adequately controlled air and rice conditions, and maintained the rice at a high level quality. The total economic benefits could add to more than 30 million dollars annually to the rice industry in the U.S. if the systems developed in this research for optimum drying and storage of rough rice are applied to the existing on-farm rice drying and storage

A study to determine the effectiveness of employee hiring programs in the catering business in the south Florida area

The purpose of this study was to determine the effectiveness of employee hiring programs in the catering business in the South Florida area. The descriptive survey method was used for the gathering of the primary data source. The study was conducted by supporting the hypothesis. The hypothesis stated that employee hiring programs in the catering business in the South Florida area are generally ineffective

A Patterned Single Layer Graphene Resistance Temperature Sensor

Micro-fabricated single-layer graphenes (SLGs) on a silicon dioxide (SiO2)/Si substrate, a silicon nitride (SiN) membrane, and a suspended architecture are presented for their use as temperature sensors. These graphene temperature sensors act as resistance temperature detectors, showing a quadratic dependence of resistance on the temperature in a range between 283 K and 303 K. The observed resistance change of the graphene temperature sensors are explained by the temperature dependent electron mobility relationship (~T−4) and electron-phonon scattering. By analyzing the transient response of the SLG temperature sensors on different substrates, it is found that the graphene sensor on the SiN membrane shows the highest sensitivity due to low thermal mass, while the sensor on SiO2/Si reveals the lowest one. Also, the graphene on the SiN membrane reveals not only the fastest response, but also better mechanical stability compared to the suspended graphene sensor. Therefore, the presented results show that the temperature sensors based on SLG with an extremely low thermal mass can be used in various applications requiring high sensitivity and fast operation

Hepatic resection of metastatic tumor from serous cystadenocarcinoma of the ovary.

Metastatic carcinomas are the largest group of malignant tumors of the liver. But parenchymal liver metastasis from cystic ovarian adenocarcinoma is very rare. We report a case in which the resection of metastatic liver neoplasm from ovarian serous cystadenocarcinoma was done 7 yr after initial treatment. A 48-yr-old oriental housewife complained of easy fatigability and right lower quadrant discomfort. The hepatic mass was detected by ultrasonographic examination. Serum albumin, bilirubin, and aspartate aminotransferase/alanine aminotransferase were normal. Alkaline phosphatase level was slightly increased at 146 IU/L. A tumor marker study showed alpha-fetoprotein 0.97 IU/mL, carcinoembryonic antigen 0.965 ng/mL, cancer antigen 125 1,267 ng/mL and CA 19-9 106.1 ng/mL. The operation involved cholecystectomy and segmentectomy VI and VII of the liver. The patient recovered from the surgery without any complication. On the 10th postoperative day, the patient received a single-regimen chemotherapy with paclitaxel (Taxol, 155 mg/m(2) BSA) and was discharged. She has been carefully followed-up without any evidence of recurrence after completion of the remaining 5 cycles of chemo-therapy, at intervals of three weeks

Dental stem cell therapy with calcium hydroxide in dental pulp capping

Calcium hydroxide has been extensively and steadily used for direct pulp capping in modern clinical dentistry. As it was known to have potential to induce hard tissue repair, this chemical has been applied to the exposed dental pulp and the hard tissue is expected to be regenerated above the pulp. During the reparative process of exposed pulp, primary odontoblasts that were lost as a result of extensive damage are replaced with newly differentiated odontoblast-like cells. This process is known to follow the sequential steps of proliferation, migration, and differentiation of progenitor cells. This research will examine the relationship between calcium hydroxide and the recruitment, proliferation, and mineralization of postnatal dental stem cells, obtained from an immature dental tissue of beagle dogs. Immunocytochemical staining and reverse transcriptase-polymerase chain reaction were used to identify the putative stem cell markers. Immunoblot analysis, wound healing assay, cell migration assay, and alizarin red staining were used to evaluate proliferation, migration, and mineralization capacity of the calcium hydroxide-treated stem cells. As an in vivo study, a combination of calcium hydroxide and autologous dental pulp stem cells (DPSCs) was applied for the treatment of intentionally created tooth defects on the premolars and the molars in beagle dogs to observe dentin regeneration. Ex vivo expanded DPSCs and periodontal ligament stem cells expressed STRO-1 and CD146, the mesenchymal stem cell markers. It was evident that calcium hydroxide increased recruitment, migration, proliferation, and mineralization of the DPSCs and periodontal ligament stem cells. Such results are valuable for future availability of DPSCs, which are recently focused as the stem cell reservoir for regeneration of dentin upon tooth injury, as well as for elucidation of the role of calcium hydroxide in pulp capping therapy.This work was supported by grants from the National Research Foundation of Korea (NRF) grant funded by the Korean government (MEST) (No. 2009-0066366) to Pill-Hoon Choung and by the Ministry of Health and Welfare, the Republic of Korea, through the Musculoskeletal Bioorgans Center Program (no. 0405-BO01-0204-0006)

Molecular Responses in Osteogenic Differentiation of Mesenchymal Stem Cells Induced by Physical Stimulation

Mesenchymal stem cells (MSCs) have been recognized as a great source of stem cells in the field of regenerative medicine and regulation of MSCs such as differentiation into specific cells. Particular interest is the use of physical stimulation for the expression of the osteoblast-specific genes from MSCs for bone tissue regeneration. The mechanical forces on MSCs, such as fluid flow, enhance the mineralized matrix and specific gene expressions. This process called mechanotransduction comprises of the steps of mechanoreception, biochemical coupling, transmission of signal and effector cell response. Physical stimuli effectively regulate extracellular and intracellular signaling pathways to enhance the expression of specific transcription factors, and the release of osteocytes, ultimately expedite the production of active osteoblasts. Thus understating, identification and functional characterization of the mechanotransduction underlying the physical stimulation of MSCs is a critical issue for devising new bone regenerative treatments for bone-related diseases. In this review, we focus on the molecular mechanism responsible for the mechanotransduction of osteogenic differentiation of MSCs induced by physical stimulation.