• 제목/요약/키워드: University of Cambridge

검색결과 216건 처리시간 0.036초

A Pilot Examination of Oxidative Stress in Trichotillomania

  • Grant, Jon E.;Chamberlain, Samuel R.
    • Psychiatry investigation
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    • 제15권12호
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    • pp.1130-1134
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    • 2018
  • Objective Trichotillomania is a relatively common illness whose neurobiology is poorly understood. One treatment for adult trichotillomania, n-acetyl cysteine (NAC), has antioxidative properties, as well as effects on central glutamatergic transmission. Preclinical models suggest that excessive oxidative stress may be involved in its pathophysiology. Methods Adults with trichotillomania provided a blood sample for analysis of compounds that may be influenced by oxidative stress [glutathione, angiotensin II, ferritin, iron, glucose, insulin and insulin growth factor 1 (IGF1), and hepcidin]. Participants were examined on symptom severity, disability, and impulsivity. The number of participants with out-of-reference range oxidative stress measures were compared against the null distribution. Correlations between oxidative stress markers and clinical measures were examined. Results Of 14 participants (mean age 31.2 years; 92.9% female), 35.7% (n=5) had total glutathione levels below the reference range (p=0.041). Other oxidative stress measures did not have significant proportions outside the reference ranges. Lower levels of glutathione correlated significantly with higher motor impulsiveness (Barratt Impulsiveness Scale sub-score) (r=0.97, p=0.001). Conclusion A third of patients with trichotillomania had low levels of glutathione, and lower levels of glutathione correlated significantly with higher motor impulsiveness. Because NAC is a precursor for cysteine, and cysteine is a rate limiting step for glutathione production, these results may shed light on the mechanisms through which NAC can have beneficial effects for impulsive symptoms. Confirmation of these results requires a suitable larger follow-up study, including an internal normative control group.

풍자 잡지 「펀치」를 통해 본 19세기 영국 사회의 수학에 대한 인식 변화 : 수학 시험의 확대와 수학 교육의 수요 변화를 중심으로 (Changes in England society's perception of mathematics in the 19th century through the satirical magazine Punch: Focusing on the expansion of mathematics tests and changes in demand for mathematics education)

  • 조수남
    • 한국수학사학회지
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    • 제35권1호
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    • pp.19-39
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    • 2022
  • This paper aims to examine how the public perception of mathematics changed in England in the 19th century. As rapid industrial and social developments took place in the 19th century, the educational environment underwent great changes, and the value and public perception of mathematics also changed. Mathematics took a new position in the terrain of educational reform in the late 19th century. In this study, I analyzed the actual condition of mathematics education in elementary and secondary schools, popular educational institutions, and universities in England in the first half, middle, and second half of the 19th century, and compared what values and usefulness of mathematics education were justified in each institution. I also examined how satirical magazine Punch satirized the public understanding or view on mathematics at each period. It is to be hoped that this study will have significant implications for raising the public's positive perception of mathematics in modern society.

Formation of globular clusters in cosmological radiation hydrodynamic simulation

  • Yi, Sukyoung K.;Kimm, Taysun
    • 천문학회보
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    • 제41권2호
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    • pp.36.1-36.1
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    • 2016
  • This is a presentation of the paper published as Kimm et al. 2016, ApJ, 823, 52. We investigate the formation of metal-poor globular clusters (GCs) at the center of two dark matter halos with $Mhalo{\sim}4{\times}107Msun$ at z>10 using cosmological radiation-hydrodynamics simulations. We find that very compact (${\leq}1$ pc) and massive (${\sim}6{\times}105Msun$) clusters form rapidly when pristine gas collapses isothermally with the aid of efficient $Ly{\alpha}$ emission during the transition from molecular-cooling halos to atomic-cooling halos. Because the local free-fall time of dense star-forming gas is very short (${\ll}1Myr$), a large fraction of the collapsed gas is turned into stars before stellar feedback processes blow out the gas and shut down star formation. Although the early stage of star formation is limited to a small region of the central star-forming disk, we find that the disk quickly fragments due to metal enrichment from supernovae. Sub-clusters formed in the fragmented clouds eventually merge with the main cluster at the center. The simulated clusters closely resemble the local GCs in mass and size but show a metallicity spread that is much wider than found in the local GCs. We discuss a role of pre-enrichment by Pop III and II stars as a potential solution to the latter issue. Although not without shortcomings, it is encouraging that a naive blind (not tuned) cosmological simulation presents a possible channel for the formation of at least some massive GCs.

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Effects of Temperature and Heavy Metals on Extractable Lipofuscin in the Blue Crab, Callinectes sapidus

  • Ju, Se-Jong;Harvey, H.R.
    • Journal of the korean society of oceanography
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    • 제37권4호
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    • pp.232-241
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    • 2002
  • The potential role of environmental factors on extractable lipofuscin accumulation rate in the blue crab was studied by examining the effect of temperature on laboratory reared blue crabs and the effect of trace metals from samples collected at impacted sites (Baltimore Harbor) and a relatively pristine site (outdoor ponds at Horn Point Laboratory, Cambridge, MD, USA). Lipofuscin levels did not significantly related with sampling sites or heavy metal concentrations in the crab tissue. Heavy metal body burden was highly variable among sampling sites and tissue types but significantly higher for both impacted areas (Curtis Creek and Inner Harbor) in comparison to the reference site. Among tissue types, gills showed the highest metal concentrations with the exception of Hg, which was highest in muscle tissue. For two groups of crabs that were held at either ambient (4 to 1$0^{\circ}C$) or heated seawater (19$^{\circ}C$) for two months, normalized-lipofuscin levels were significantly different (P-0.001). Results suggest that temperature may affect lipofuscin accumulation (=0.25ng-lipofuscin/mg-protein/temperature-degree day). Therefore, temperature should be considered for accurate age calibration of crab populations using lipofuscin.

조현병 환자와 발병하지 않은 형제에게서 연성신경학적 징후 연구 (A Study of Neurological Soft Signs in Patients with Schizophrenia and Their Unaffected Siblings)

  • 조장원;김석현;이유상
    • 생물정신의학
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    • 제23권4호
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    • pp.179-184
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    • 2016
  • Objectives This study was conducted to investigate the possibility of neurological soft signs as an endophenotype for schizophrenia by examining neurological soft signs in patients, their unaffected siblings and normal comparison subjects. Methods The study sample consisted of 32 patients, 25 of their unaffected siblings and 30 normal comparison subjects. Neurological soft signs were evaluated using the Cambridge Neurological Inventory Part 2. soft sign assessment. Results The patients were significantly more impaired than normal comparison subjects (p = 0.047) on primitive reflex. The patients were significantly more impaired than siblings (p = 0.004) and normal comparison subjects (p = 0.021) on motor coordination. The siblings performed better on sensory integration than the patients (p = 0.020) and normal comparison subjects (p = 0.036). Conclusions This study suggests that neurological soft signs might be a potential biomarker for schizophrenia, but might not be an endophenotype for schizophrenia.

The Mathematical Knowledge of Elementary School Teachers: A Comparative Perspective

  • Wong, Ngai-Ying;Rowland, Tim;Chan, Wing-Sum;Cheung, Ka-Luen;Han, Ngai-Sze
    • 한국수학교육학회지시리즈D:수학교육연구
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    • 제14권2호
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    • pp.173-194
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    • 2010
  • This study examines the differences and similarities of mathematics teachers' subject matter knowledge among England, the Chinese mainland and Hong Kong. Data were collected from a ten-item test in the SKIMA subject matter audit instrument [Rowland, T.; Martyn, S.; Barber, P. & Heal, C. (2000). Primary teacher trainees' mathematics subject knowledge and classroom performance. In: T. Rowland & C. Morgan (eds.), Research in Mathematics Education, Volume 2 (pp.3-18). ME 2000e.03066] from over 500 participants. Results showed that participants from England performed consistently better, with those from Hong Kong being next and then followed by those from the Chinese mainland. The qualitative data revealed that participants from Hong Kong and the Chinese mainland were fluent in applying routines to solve problems, but had some difficulties in offering explanations or justifications.

How Firms Develop Linkages for Development and Growth - Cases in Malaysian Greenfield and Brownfield Technology Parks

  • Mohan, Avvari V.;Ismail, Isshamudin
    • World Technopolis Review
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    • 제4권2호
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    • pp.87-103
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    • 2015
  • This paper aims to explore how firms develop and grow in regional clusters based in a developing country. The argument is that start-ups / small and large firms are able to grow by developing linkages or networks for resources within clusters - and this tenet is based on studies of firms that are based from such clusters as Silicon Valley in the US, Cambridge in UK and other clusters from which have evolved over long periods of time. Most of the time we hear narratives from the developed world where there are brownfield cluster development efforts. In developing countries governments are making efforts to develop clusters from scratch - which in this paper we term as greenfield cluster versus a brownfield development, which is where the cluster is developed based on existing and new organisations in a region. In this paper, we believe the context of clusters can be important in determining the way firms develop linkages for their growth - and we look at two contexts in Malaysia ie. A greenfield cluster and a brownfield cluster. The paper presents findings from case studies of firms in a greenfield cluster (Cyberjaya) and a brown field cluster (Penang) in Malaysia. The cases reveal fairly different approaches to development of linkages or networks, which we hope will provides insights to cluster development officials and policy makers and implications to researchers for developing studies of clusters and innovation systems.

효율적인 가시광 활성 음이온 도핑 광촉매 (Efficient Visible Light Activated Anion Doped Photocatalysts)

  • 인수일
    • Korean Chemical Engineering Research
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    • 제49권5호
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    • pp.505-509
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    • 2011
  • 가시광 영역에서 활성을 보이는 광촉매는 태양광을 이용한 광촉매분해, $CO_2$ 변환을 위한 융합 시스템과 물로부터 수소를 생산하는 분야에 있어서의 높은 실현 가능성 때문에 최근 많은 주목을 받고 있다. 현재의 합성방법은 높은 비용과 비재현성, 도핑 물질의 양을 조절하는 어려움 그리고 대량 생산의 불안정성 때문에 상용화의 어려움을 겪고 있다. 본 총설에서는 케임브리지 대학 Lambert 그룹에서 개발된 재현가능하고 컨트롤이 용이한 자연광 활성 음이온 도핑 $TiO_2$ 광촉매에 관해서 요약하였다.

The Impact of Word of Mouth on Customer Perceived Value for the Malaysian Restaurant Industry

  • Oluwafemi, Adebusoye Shedrack;Dastane, Omkar
    • Asian Journal of Business Environment
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    • 제6권3호
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    • pp.21-31
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    • 2016
  • Purpose - The purpose of this research is to determine the impact of word of mouth on customer perceived value for restaurants in Malaysia. The objectives of this research include determining how word of mouth (WoM) factors - frequency of word of mouth messages, reputation of word of mouth messenger, richness of word of mouth message, dispersion of word of mouth conversations and manner of word of mouth delivery impact customer perceived value in Malaysian restaurant industry. Research Design, Data, and Methodology - The research follows causal / explanatory research method based on quantitative data. A sample of 150 restaurant customers in Kuala Lumpur, Malaysia was selected using convenience sampling technique. Likert scale questionnaire is used to collect data and data is analysed using regression analysis through SPSS 22. Results - The statistical analysis revealed that independent variable 'manner of delivery' significantly and positively impacts customer perceived value for restaurants in Malaysia. Conclusions - To build strong positive customer perception, Malaysian restaurants can enhance word of mouth campaigns' 'manner of delivery' by making them passionate, exciting and with high emotional appeal.

Effective Interdiffusion of Co/Pd multilayers

  • Kim, Jai-Young;Jan E. Evetts
    • Journal of Magnetics
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    • 제2권3호
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    • pp.86-92
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    • 1997
  • An artificially modulated magnetic Co/Pd multilayer is one of the promising candidates for high density magneto-optic (MO) recording media in the wavelength of a blue laser beam, due to large Kerr rotation angle. However, since the Co/Pd multilayer is a non-equilibrium state in terms of free energy and MO recording is a kind of thermal recording which is conducted around Curie temperature (Tc) of the recording media, the assessment of the thermal stability in the Co/Pd multilayer is crucially important both for basic research and applications. As the parameter of the thermal stability in this research, effective interdiffusion coefficients (Deff) perpendicular to the interface of the Co/Pd multilayers are measured in terms of Ar sputtering pressure and heat treatment temperature. From the results of the research, we find out that the magnetic exchange energy between Co and Pd sublayers strongly affects Deff of the Co/Pd multilayers. This discovery will provide the understanding of the magnetic exchange energy in the effective interdiffusion process of a magnetic multilayer structure and suggest the operating temperature range for MO recording in the Co/Pd multilayer for the basic research and applications, respectively.

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