Community College Student Engagement Patterns: A Typology Revealed Through Exploratory Cluster Analysis

This study employs survey data from the Center for Community College Student Engagement to examine the similarities and differences that exist across student-level domains in terms of student engagement in community colleges. In total, the sample used in the analysis pools data from 663 community colleges and includes more than 320,000 students. Using data-mining techniques to discover a parsimonious number of natural clusters and, in turn, a k-means cluster analysis as a means of revealing a naturally occurring typology of engagement patterns, our findings reveal that support service utilization is the most distinguishing feature of the similarities and dissimilarities across student groups, suggesting areas for further theory development and testing

Community College Student Engagement Patterns: A Typology Revealed Through Exploratory Cluster Analysis

This study employs survey data from the Center for Community College Student Engagement to examine the similarities and differences that exist across student-level domains in terms of student engagement in community colleges. In total, the sample used in the analysis pools data from 663 community colleges and includes more than 320,000 students. Using data-mining techniques to discover a parsimonious number of natural clusters and, in turn, a k-means cluster analysis as a means of revealing a naturally occurring typology of engagement patterns, our findings reveal that support service utilization is the most distinguishing feature of the similarities and dissimilarities across student groups, suggesting areas for further theory development and testing

Parathyroidectomy versus cinacalcet in the treatment of tertiary hyperparathyroidism after kidney transplantation: a retrospective study

Background Hyperparathyroidism is common in patients with chronic kidney disease with reduced renal function and has been observed after kidney transplantation. The optimal treatment for cases in which hyperparathyroidism persists after kidney transplantation has not been determined. Methods This retrospective study included 83 patients with tertiary hyperparathyroidism who underwent kidney transplantation between 2000 and 2018 at a single tertiary center in Korea. Sixty-four patients underwent parathyroidectomy and 19 patients were treated with cinacalcet following renal transplantation. Biochemical parameters and clinical outcomes were compared between the two groups. Results Serum calcium and parathyroid hormone (PTH) levels improved in both the parathyroidectomy and cinacalcet groups. One year after treatment, parathyroidectomy resulted in a lower mean serum calcium level than cinacalcet (9.7 ± 0.7 mg/dL vs. 10.5 ± 0.7 mg/dL, p = 0.001). Regarding serum PTH, the parathyroidectomy group showed a significantly lower PTH level than the cinacalcet group at 6 months (129.1 ± 80.3 pg/mL vs. 219.2 ± 92.5 pg/mL, p = 0.002) and 1 year (118.8 ± 75.5 pg/mL vs. 250.6 ± 94.5 pg/mL, p < 0.001). There was no statistically significant difference in the incidence of kidney transplant rejection, graft failure, cardiovascular events, fracture risk, or bone mineral density changes between the two groups. Conclusion Parathyroidectomy appears to reduce PTH and calcium levels effectively in tertiary hyperparathyroidism. However, creatinine level and allograft rejection should be monitored closely

A New Recycling Process for Tungsten Carbide Soft Scrap That Employs a Mechanochemical Reaction with Sodium Hydroxide

WC soft scrap, including Co used as a binder, thermally oxidized at 600 °C, was subjected to grinding with NaOH in a mechanochemical reaction, followed by water leaching to establish an effective recycling process. Na2WO4 was synthesized through a mechanochemical (MC) reaction with oxidized scrap, and Na2CO3 was formed when the mixing ratio of NaOH increased. These as-synthesized compounds were water-soluble. When the weight ratio of soft scrap to NaOH was 1:0.5, 99.2% W was extracted by water leaching, while the extraction yield of Co was limited to 3.57% under the same conditions

A Numerical Study for Performance Prediction of a Metal Hydride Thermal Energy Conversion System Elaborating the Superadiabatic Condition

In this study, we investigate a numerical-modeling method uniquely performing analyses of 50 different metal hydrides to find the optimized thermal effect. This paper presents a metal-hydride thermal energy conversion method, which offers an alternative approach to the traditional vapor-compression heat pump associated with conventional heating, ventilation, and air conditioning (HVAC). The authors have developed an innovative heat pump applicable to non-vapor compression-based systems, which are in compliance with low-temperature heat source requirements for operation. The new heat pump has a high-energy savings potential for both heating and cooling that featured two different metal-hydrides, that are distributed inside parallel channels filled with porous media. Thermal energy conversion is developed as a set of successive thermal waves. The numerical-modeling results present the enhanced thermal effect, which is attained in a synchronous motion of the thermal waves and the heat source (or sink) inside paired porous media channels, which accompanies the phase transition in the succession of unit metal-hydride heat pumps. The results present in a form convenient for the prediction of thermal energy efficiency based on the proposed thermal-conversion method in real devices that were experimentally verified in previous work. The non-vapor technologies will be operational with low energy input, which makes it possible to utilize waste heat or low-level heat often found in the environment such as solar radiation, exhaust gas from a heat engine, or high-temperature fuel cell system

Seed Germination and Seedling Growth of Four Bedding Plants in Substrate Containing Coal Bottom Ash Mixed with Coir Dust

Coal bottom ash (BA) is a by-product of coal-fired power generation and can be utilized as a growing substrate for ornamental plants. The physical and hydraulic properties of BA-mixed substrates (coir dust:BA, 10:0, 9:1, 8:2, 7:3, and 6:4, v/v) and commercial germinating media (BM2; Berger Peatmoss) were investigated, and the effects of the substrate mixtures on seed germination, seedling growth, and heavy metal concentrations (Cd and Pb) were evaluated for four common bedding plants (periwinkle (Catharanthus roseus), globe amaranth (Gomphrena globose), impatiens (Impatiens walleriana), and petunia (Petunia multiflora)). As the BA:coir dust increased, the air space rate in the substrate increased from 25.5 to 28.0%, providing the substrate with sufficient porosity. However, the container capacity and amount of easily available water decreased from 63.1 to 53.7% as BA proportions increased. In the final germination percentage and days to germination of the four bedding plants, no significant differences were detected among the substrate mixtures. Although the impatiens and petunias displayed poor growth (46–55% and 42–56% of dry weight, respectively) in the BA-mixed substrates compared to the BM2, no apparent differences in the seedling growth of periwinkles and globe amaranths were found between 7:3 (coir dust:BA) substrate and BM2. These results indicated that the BA-mixed substrates had the potential to replace the commercial germinating media. The plants grown in the BA-mixed substrates contained Cd, but it was unlikely to be derived from the BA

Effect of Mechanical Activation on the Kinetics of Copper Leaching from Copper Sulfide (CuS)

The effect of mechanical activation on the copper leaching of copper sulfide, CuS, in 1 M HNO3 (slurry density: 10 g/L) was investigated by analysis of the leachability and the apparent activation energy. Mechanical activation produced an increase in the leachability and a decrease of the activation energy in this leaching reaction. The leachability increased proportionally to the degree of mechanical activation, reaching 96.6% leaching within 60 min at 80 °C from CuS ground at 700 rpm for 15 min. This leaching process was controlled by surface chemical reaction following the shrinking-core model. The apparent activation energy of leaching for CuS (71.5 kJ/mol) in the range of 50 to 80 °C decreased with an increase of the degree of mechanical activation, reaching 44.3 kJ/mol for Cu leaching from CuS ground at 700 rpm for 15 min

2-O-Methylhonokiol Suppresses HCV Replication via TRAF6-Mediated NF-kB Activation

Hepatitis C virus (HCV) is associated with various liver diseases. Chronic HCV infection is characterized by an abnormal host immune response. Therefore, it is speculated that to suppress HCV, a well-regulated host immune response is necessary. 2-O-methylhonokiol was identified by the screening of anti-HCV compounds using Renilla luciferase assay in Huh 7.5/Con 1 genotype 1b replicon cells. Here, we investigated the mechanism by which 2-O-methylhonokiol treatment inhibits HCV replication using real-time PCR. Our data shows that treatment with 2-O-methylhonokiol activated innate immune responses via nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB) pathway. Additionally, the immunoprecipitation result shows that treatment with 2-O-methylhonokiol augmented tumor necrosis factor receptor (TNFR)-associated factor 6 (TRAF6) by preventing p62 from binding to TRAF6, resulting in reduced autophagy caused by HCV. Finally, we reproduced our data with the conditioned media from 2-O-methylhonokiol-treated cells. These findings strongly suggest that 2-O-methylhonokiol enhances the host immune response and suppresses HCV replication via TRAF6-mediated NF-kB activation