Optical Absorption Enhancement by Mechanical Twins Grown Using Low Temperature Silicon Epitaxy

AbstractThis paper presents the results of thin film silicon (Si) solar cells with in-situ doped epitaxial emitter deposited on Si substrate by rapid thermal chemical vapor deposition (CVD). High resolution transmission electron microscopy (HRTEM) images reveal that low temperature Si epitaxy growth induces mechanical twins at the junction interface. The presence of the twins alters the orientation of the crystal planes, increases the optical path length of light within the epitaxy film and improves the optical absorption. On the other hand, these twins appear to be the main cause for material-induced shunting at the p-n junction. Photoluminescence (PL) mapping indicate that lower growth temperature results in better interface quality

Closing the gap: Pre-service teachers' perceptions of an ICT based, student centred learning curriculum

As technology continues to influence many aspects of our social and work lives, it is important that school experiences equip students the skills and knowledge that will enable them to develop into effective independent, creative, and lifelong learners to cope with the influx of changes. Given that teachers play a key role in the effective use of technology in education, there is a need to ensure that teacher education programs prepare teachers for the effective integration of ICT in the classrooms. We believe that there is a need to adopt a student-centered learning framework to design our ICT based Student-Centred Learning (SCL) curriculum for all pre-service teachers. In this paper, we presents parts of the findings from a curriculum review which evaluated 483 pre-service teachers' overall satisfaction level towards an ICT based SCL course. We also provide some recommendations to the ICT curriculum based on the results found. © 2007 Chwee Beng Lee, Timothy Teo, Ching Sing Chai, Doris Choy, Ashley Tan and Jimmy Seah

MENJALIN KERJASAMA DENGAN PEMUDA KARANGTARUNA UNTUK MENINGKATKAN KUALITAS LINGKUNGAN

Rendahnya kesadaran masyarakat Kelurahan Putat Jaya (eks-lokalisasi Dolly) RT 03, Kota Surabaya akan pentingnya pengelolaan sampah yang ditandai dengan siklus pembuangan sampah selama lima hari sekali menyebabkan kualitas lingkungan yang buruk. Hal ini juga diperparah dengan kualitas tempat sampah yang kurang memadai sehingga banyak sampah menumpuk dan berserakan di luar tempat sampah dan wilayah tersebut terkesan kumuh. Sebuah kegiatan untuk meningkatkan kesadaran masyarakat akan pentingnya pengelolaan sampah perlu dilaksanakan sehingga mahasiswa Universitas Kristen Petra bekerja sama dengan pemuda karangtaruna melaksanakan kegiatan service learning. Diharapkan melalui kegiatan ini, masyarakat dapat meningkatkan kesadaran akan pengelolaan sampah agar bisa menciptakan lingkungan yang bersih dan sehat. Di akhir acara diadakan makan bersama untuk mempererat hubungan dengan masyarakat. Dari survei yang dilakukan mengindikasikan 98% responden menyatakan bahwa kerjasama antara mahasiswa dan masyarakat khususnya pemuda karangtaruna pada rangkaian kegiatan service learning telah berjalan dengan baik. 100% responden juga merasa terbantu dengan diadakannya kegiatan ini dan mengharapkan agar kegiatan ini dapat terus dilakukan kembali

Genetic and bioinformatic analyses of the expression and function of PI3K regulatory subunit PIK3R3 in an Asian patient gastric cancer library

10.1186/1755-8794-5-34BMC Medical Genomics5

Mixed-location cerebral microbleeds as a biomarker of neurodegeneration in a memory clinic population

Cerebral microbleeds (CMBs) in the lobar and deep locations are associated with two distinct pathologies: cerebral amyloid angiopathy and hypertensive arteriopathy. However, the role of mixed-location CMBs in neurodegeneration remains unexplored. We investigated the associations between strictly lobar, strictly deep and mixed-location CMBs with markers of neurodegeneration. This study recruited 477 patients from a memory clinic who underwent 3T MRI scans. CMBs were categorized into strictly lobar, strictly deep and mixed-location. Cortical thickness, white matter volume and subcortical structural volumes were quantified using Free-Surfer. Linear regression models were performed to assess the association between CMBs and cerebral atrophy, and the mean difference (β) and 95% confidence intervals (CIs) were reported. In the regression analyses, mixed-location CMBs were associated with smaller cortical thickness of limbic region [β=-0.01; 95% CI=-0.02,-0.00, p=0.007) as well as with smaller accumbens volume [β=-0.01; 95% CI=-0.02,-0.00, p=0.004) and presubiculum region of hippocampus [β=-0.01; 95% CI=-0.02,-0.00, p=0.002). Strictly lobar CMBs were associated with smaller total white matter volume [β=-0.03; 95% CI=-0.04,-0.01, p<0.001] and with region specific white mat

Cost-benefit analysis of introducing next-generation sequencing (metagenomic) pathogen testing in the setting of pyrexia of unknown origin

Pyrexia of unknown origin (PUO) is defined as a temperature of >38.3°C that lasts for >3 weeks, where no cause can be found despite appropriate investigation. Existing protocols for the work-up of PUO can be extensive and costly, motivating the application of recent advances in molecular diagnostics to pathogen testing. There have been many reports describing various analytical methods and performance of metagenomic pathogen testing in clinical samples but the economics of it has been less well studied. This study pragmatically evaluates the feasibility of introducing metagenomic testing in this setting by assessing the relative cost of clinically-relevant strategies employing this investigative tool under various cost and performance scenarios using Singapore as a demonstration case, and assessing the price and performance benchmarks, which would need to be achieved for metagenomic testing to be potentially considered financially viable relative to the current diagnostic standard. This study has some important limitations: we examined only impact of introducing the metagenomic test to the overall diagnostic cost and excluded costs associated with hospitalization and makes assumptions about the performance of the routine diagnostic tests, limiting the cost of metagenomic test, and the lack of further work-up after positive pathogen detection by the metagenomic test. However, these assumptions were necessary to keep the model within reasonable limits. In spite of these, the simplified presentation lends itself to the illustration of the key insights of our paper. In general, we find the use of metagenomic testing as second-line investigation is effectively dominated, and that use of metagenomic testing at first-line would typically require higher rates of detection or lower cost than currently available in order to be justifiable purely as a cost-saving measure. We conclude that current conditions do not warrant a widespread rush to deploy metagenomic testing to resolve any and all uncertainty, but rather as a front-line technology that should be used in specific contexts, as a supplement to rather than a replacement for careful clinical judgement

Control of immune cell entry through the tumour vasculature: a missing link in optimising melanoma immunotherapy?

Metastatic melanoma remains a fatal disease to many worldwide, even after the breakthrough introduction of targeted therapies such as BRAF inhibitors and immune checkpoint blockade therapies such as CTLA-4 and PD-1 inhibitors. With advances in our understanding of this disease, as well as the increasing data gathered from patient studies, the significance of the host immune response to cancer progression and response to treatment is becoming clear. More specifically, the presence of intratumoral CD8⁺ cytotoxic T-cells correlates with better prognosis whereas the accumulation of monocytes/macrophages and neutrophils in the tumour is often associated with worse prognosis. Access and infiltration of circulating leukocytes into the tumour is governed by adhesion molecules and chemokines expressed by the endothelial cells of the vasculature. This review focuses on the adhesion molecules and chemokines which control the homing of CD8⁺ cytotoxic T-cells, monocytes and neutrophils to peripheral tissues, including tumours. We discuss the role of these leukocyte subsets in regulating melanoma growth, and detail the mechanisms used by tumours to selectively recruit or exclude these leukocytes for their own advantage. In doing so, we bring to light an underappreciated component of tumour biology which should be considered in combination with current treatments to selectively alter the leukocyte composition of tumours and ultimately enhance treatment outcome.Lih Yin Tan, Carmela Martini, Zvi G Fridlender, Claudine S Bonder, Michael P Brown and Lisa M Eber