3D integration of micro- and nanostructures into bio-analytical devices

This study aims to develop a process which allows 3D integration of micro and nanostructures in microchannels. A fabrication process was established for the large area integration of hierarchical micro and nanostructures in microchannels. This novel process, which is called 3D molding, takes advantage of an intermediate thin flexible stamp such as PDMS from soft lithography and a hard mold such as brass from hot embossing process. However, the use of a thin intermediate polydimethylsiloxane (PDMS) stamp inevitably causes dimensional changes in the 3D molded channel, with respect to those in the brass mold protrusion and the intermediate PDMS stamp structures. We have investigated the deformation behavior of the 3D molded poly(methyl methacrylate) (PMMA) substrate and the intermediate PDMS stamp in 3D molding through both experimentation and numerical simulation. It was found that for high aspect ratio brass mold protrusion, the maximum strain of the intermediate layer occurs in the bottom center of the 3D channels. However, with decreasing the aspect ratio of brass mold protrusion the highest elongation occurs at the bottom corners of the channel causing less elongation of the intermediate PDMS stamp and imprinted structures on the bottom surface of the 3D channel. A modified 3D molding process which is called 3D nanomolding is developed which allows nanopatterning the surface of small microfeatures. Using 3D nanomolding process and solvent assisted bonding microdevices with no side, one side, three sides and four sides patterned were fabricated. To characterize 3D flow patterns induced by the surface structures on microdevices, confocal microscopy was used as dyed water and undyed water injected from separate inlets of micromixer were mixed along the microchannel at flow rates of 10 and 40 μL/min. The standard deviation of the normalized intensity measured in the confocal image of the cross section of the channel was used for quantifying the degree of mixing and evaluating the mixing performance of all four different microdevices. Experimental and simulation results show that by patterning the surface of the micromixer, flow patterns can be manipulated, which can improve mixing through stretching and folding of fluid elements and therefore increasing the interfacial area between fluids and cutting down the diffusion length. The effect of increasing velocity on increasing standard deviation (decreasing mixing) was also found to be less for the micromixers whose surfaces are patterned compared to the plain channel

LearningCare sebagai Sistem Pengurusan Pembelajaran : amalan dan tahap kepuasan pelajar kursus teknologi pendidikan Universiti Utara Malaysia

LearningCare merupakan satu Sistem Pengurusan Pembelajaran (Learning Management System) atau sistem pembelajaran elektronik (e-pembelajaran) yang berasaskan lnternet dan diintegrasikan sepenuhnya dengan sistem akademik Universiti Utara Malaysia. la mula digunakan pada bulan November 2002. Sistem ini membolehkan tenaga akademik meletak bahan pengajaran untuk dicapai oleh pelajar di mana jua dan pada bila-bila masa (anywhere and anytime). Selain itu LearningCare juga membenarkan tenaga akademik berinteraksi dengan pelajar melalui forum dalam talian, menghebahkan pengumuman, menjalankan ujian atau kuiz secara dalam talian serta berupaya mengesan dan memantau penglibatan pelajar dalam menggunakan LearningCare. LearningCare dan proses pengajaran perlu diintergarsikan dengan sebaiknya untuk menghasilkan proses pengajaran dan pembelajaran yang berkesan. Kajian ini dijalankan untuk melihat amalan dan tahap kepuasan pelajar kursus Teknologi Pendidikan Universiti Utara Malaysia dalam menggunakan LearningCare bagi membantu proses pembelajaran mereka. Dapatan kajian menjelaskan, pelajar sangat berpuas hati dengan perkhidmatan yang disediakan di dalam LearningCare dan ianya banyak menbantu pelajar dalam proses pembelajaran mereka

Multimedia Interaktif Dalam Pembelajaran Teknologi Maklumat Kurikulum Baru Sekolah Menengah Peringkat Sijil Pelajaran Malaysia

Computer in education refers to the use of computer as a tool to help and enrich the teaching and learning process. The objective is of course to preserve the quality of education by improving the effectiveness of teaching and learning. Interactive Multimedia in Information Technology learning in KBSM at the SPM level consists of two main parts. First, the development of Interactive Multimedia Software Prototype for teaching and learning process of Information technology under the topic of Computer System. The second part on the other hand, covers the testing process on software prototypes i.e. whether it is suitable to be used in class. For this purpose a survey has been carried out among the students of Kolej Matrikulasi Perlis. The results however show that there is no significant prove or evidence that interactive multimedia technology can replace teaching and learning in class while at the same time get students' interest to learn information technology. Nevertheless, the combination of multimedia elements used is helpful in the information explanation process. But as a whole, the average agrees that the questionnaire in the survey has done justice

Distractibility in daily life is reflected in the structure and function of human parietal cortex

We all appreciate that some of our friends and colleagues are more distractible than others. This variability can be captured by pencil and paper questionnaires in which individuals report such cognitive failures in their everyday life. Surprisingly, these self-report measures have high heritability, leading to the hypothesis that distractibility might have a basis in brain structure. In a large sample of healthy adults, we demonstrated that a simple self-report measure of everyday distractibility accurately predicted gray matter volume in a remarkably focal region of left superior parietal cortex. This region must play a causal role in reducing distractibility, because we found that disrupting its function with transcranial magnetic stimulation increased susceptibility to distraction. Finally, we showed that the self-report measure of distractibility reliably predicted our laboratory-based measure of attentional capture. Our findings distinguish a critical mechanism in the human brain causally involved in avoiding distractibility, which, importantly, bridges self-report judgments of cognitive failures in everyday life and a commonly used laboratory measure of distractibility to the structure of the human brai

Monitoring hate speech and the limits of current definition

Current definitions of hate speech are inadequate as the basis for monitoring hate speech targeted at groups. First, they do not capture escalating group-targeted negative speech which can be a precursor to more extreme forms of hate speech such as dehumanization, demonization, and incitement to violence. While not hate speech, such negative speech is an early warning that could be helpful for a hate speech monitoring system to track, as responses and interventions, especially to the offline harms of hate speech, can take time to operationalize. Second, current definitions of hate speech do not capture hateful rhetoric aimed at groups not traditionally included in hate speech definitions (those without immutable qualities), such as groups targeted for hate based on profession-based identity like journalists. This chapter presents some suggestions for addressing these issues, including a hate speech intensity scale