198 research outputs found
Immigration, Cultural Adjustment, and Work Values : The Case of Korean Nail Care Workers in New York
This study addresses the significance of acculturation, known as cultural adjustment, in examining work values among Korean female nail care workers in New York. In this study, acculturation is measured by both English proficiency and personal comfort in the mainstream cultural comfort, while four indicators are used to measure work values: the subjective evaluation of the nature of the work, both perceptions of occupational status and self-development, and the consideration of quitting the current nail job. Using a sample of 312 responses, this study shows that nail care workers have evaluated the nature of the nail care work less devalued as they experience improvements in English proficiency and cultural comfort. Second, this study also supports that cultural comfort plays a positive effect on their perception of nail care work as an employment sector in a upper-middle or upper occupational status. Moreover, there is evidence that more cultural comfort tends to lower their intention of quitting the nail care job. However, this study suggests that acculturation has little to do with perception of self-development in nail care work
Ruthenium Bottom Electrode Prepared by Electroplating for a High-density DRAM Capacitor
The possibility of Ru electroplating for application as the bottom electrode in high density dynamic random access memory
~DRAM! capacitors was investigated. Prior to Ru electroplating on a TiN substrate, HF cleaning and Pd activation were performed.
Removal of Ti oxide from the TiN substrate by HF treatment enabled Pd activation, which enhanced the nucleation of Ru
on TiN substrate. Optimized pretreatments led to a continuous Ru film deposition. The surface roughness was measured to be 4.4
nm at 45 nm Ru film on the bare substrate. Moreover Ru electroplating method was also applied to a capacitor node-type TiN
wafer. The deposition rate of Ru on the patterned wafer was the same as that on a bare wafer. The film showed 93% step coverage
and good adhesion, comparable to CVD Ru films
The Impact of International Migration on Unemployment Rates in Urban America: Testing Different Theoretical Approaches
This study examines the influence of international migration on unemployment rates in urban America. For this purpose, this study first applies competition and discrimination and assimilation views in examining whether the size and composition of immigrant populations in American metropolitan areas affect urban unemployment rates. Based on local human capital and labor market views, this study also explores whether urban unemployment rates are affected by local human capital (education) and urban labor markets (employment distributions by class of workers), both of which vary with the size and compositions of local immigrant populations. Using a sample of the 301 Primary Metropolitan Statistical Areas /Metropolitan Statistical Areas (PMSAs/MSAs) in 1990 and 2000, this study employs regression models to test four hypotheses. First, the result supports to some degree competition and discrimination and assimilation views. The empirical findings show that more concentration of international migrants in urban areas, including recent immigrant cohorts, tends to increase urban unemployment rates. Second, the models of local human capital also support that growing college graduates play a role in reducing urban unemployment rates after controlling for the volume of immigrant population. However, there are conflicting impacts of local labor market (employment conditions) on urban unemployment rates
Comparison of Surgical Outcomes in Thoracolumbar Fractures Operated with Posterior Constructs Having Varying Fixation Length with Selective Anterior Fusion
PURPOSE: Surgical treatment in the case of thoracolumbar burst fractures is very controversial. Posterior instrumentation is most frequently used, however, but the number of levels to be instrumented still remains a matter of debate.
MATERIALS AND METHODS: A total of 94 patients who had a single burst fracture between T11 and L2 were selected and were managed using posterior instrumentation with anterior fusion when necessary. They were divided into three groups as follows; Group I (n = 28) included patients who were operated by intermediate segment fixation, Group II (n = 32) included patients operated by long segment fixation, and Group III (n = 34) included those operated by intermediate segment fixation with a pair of additional screws in the fractured vertebra. The mean follow-up period was twenty one months. The outcomes were analyzed in terms of kyphosis angle (KA), regional kyphosis angle (RA), sagittal index (SI), anterior height compression rate, Frankel classification, and Oswestry Disability Index questionnaire.
RESULTS: In Groups II and III, the correction values of KA, RA, and SI were much better than in Group I. At the final follow up, the correction values of KA (6.3 and 12.1, respectively) and SI (6.2 and 12.0, respectively) were in Groups II and III found to be better in the latter.
CONCLUSION: The intermediate segment fixation with an additional pair of screws at the fracture level vertebra gives results that are comparable or even better than long segment fixation and gives an advantage of preserving an extra mobile segment.ope
Occurrence of microplastics in municipal sewage treatment plants: a review
Municipal sewage treatment plants (STPs) are thought to be important point sources of microplastics in freshwater systems and many peer-reviewed articles have been published on this issue since mid-2010s. In this review, we summarize existing literature on the occurrence of microplastics in STPs and experimental methods used for isolation and identification of microplastics. The number concentrations of microplastics in STP influents were 15.1-640 L-1, whereas those in the STP effluents were highly variable and ranged from not detectable to 65 L-1. For most of cases, conventional STPs are removing microplastics very effectively. Fragments and fibers are dominant shapes of microplastics. Thermoplastics (polyethylene and polypropylene) and polyester are the predominant materials recovered. Although further research is needed, size distribution of microplastics in STPs is likely to follow a power law, implying that different studies using different size cutoffs may be compared after establishing a power law relationship
The Risk of Cytomegalovirus Infection in Non-myeloablative Peripheral Stem Cell Transplantation Compared with Conventional Bone Marrow Transplantation
Non-myeloablative allogeneic peripheral stem cell transplantation (NST) is a novel therapeutic strategy for patients with hematologic malignancies. Whether non-myeloablative transplants are associated with increased risk of cytomegalovirus (CMV) infections is unknown. To clarify this issue, we compared the outcome of CMV infection following 24 allogeneic non-myeloablative peripheral blood stem cell transplants and 40 conventional bone marrow transplants (CBT). The NST regimen consisted of busulfan (4mg/kg/day), fludarabine (30mg/m2) and anti-thymocyte globulin (10 mg/kg). Twelve patients (50%) in the NST group and 17 (43%) in the CBT group developed positive antigenemia before day 100 (p=0.60). The time to the first appearance of positive antigenemia was not different between these two groups (p=0.40), and two groups showed similar initial and maximal antigenemia values (p=0.56 and p=0.68, respectively). Only one case of CMV colitis developed in the CBT group whereas CMV disease did not develop in the NST group. Although statistically insignificant, the treatment response against CMV antigenemia using ganciclovir was in favor of NST group. In conclusion, there was no difference in the risk of CMV infection between NST group and CBT group. Further prospective and controlled study is needed to clarify the impact of non-myeloablative procedure on the outcome of CMV infection
Pulsed Electromagnetic Field Stimulates Cellular Proliferation in Human Intervertebral Disc Cells
โThe authors have no financial conflicts of interest. Purpose: The purpose of this study is to investigate the mechanism of cellular proliferation of electromagnetic field (EMF) on human intervertebral disc (IVD) cells. Materials and Methods: Human IVD cells were cultured three-dimensionally in alginate beads. EMF was exposed to IVD cells with 650 ฮช, 1.8 millitesla magnetic flux density, 60 Hz sinusoidal wave. Cultures were divided into a control and EMF group. Cytotoxicity, DNA synthesis and proteoglycan synthesis were measured by MTT assay, [ 3 H]-thymidine, and [ 35 S]-sulfate incorporation. To detect phenotypical expression, reverse transcription-polymerase chain reactions (RT-PCR) were performed for aggrecan, collagen type I, and type II mRNA expression. To assess action mechanism of EMF, IVD cells were exposed to EMF with N G-Monomethyl-L-arginine (NMMA) and acetylsalicylic acid (ASA). Results: There was no cytotoxicity in IVD cells with the EMF group in MTT assay. Cellular proliferation was observed in the EMF group (p < 0.05). There was no difference in newl
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