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Research support: models and professionalisation
This presentation was given by Mr Simon Kerridge, Secretary of the Association of Research Managers and Administrators (ARMA), at the BRAM-NET Annual Event on the 17th February 2011. The event was organised by Dr Rosa Scoble and hosted at Brunel University. BRAM-NET (The Brunel Research Administrators & Managers Network) is a forum to share best practice and information on new initiatives between colleagues supporting research in the centre and academic areas at Brunel University
Architectures for RF Frequency synthesizers
Frequency synthesizers are an essential building block of RF communication products. They can be found in traditional consumer products, in personal communication systems, and in optical communication equipment. Since frequency synthesizers are used in many different applications, different performance aspects may need to be considered in each case. The main body of the text describes a conceptual framework for analyzing the performance of PLL frequency synthesizers, and presents optimization procedures for the different performance aspects. The analysis of the PLL properties is performed with the use of the open-loop bandwidth and phase margin concepts, to enable the influence of higher-order poles to be taken into account from the beginning of the design process. The theoretical system analysis is complemented by descriptions of innovative system and building block architectures, by circuit implementations in bipolar and CMOS technologies, and by measurement results. Architectures for RF Frequency Synthesizers contains basic information for the beginner as well as in-depth knowledge for the experienced designer. It is widely illustrated with practical design examples used in industrial products.\ud
Written for:\ud
Electrical and electronic engineer
Chondrogenic potential of human articular chondrocytes and skeletal stem cells: a comparative study
Regenerative medicine strategies have increasingly focused on skeletal stem cells (SSCs), in response to concerns such as donor site morbidity, dedifferentiation and limited lifespan associated with the use of articular chondrocytes for cartilage repair. The suitability of SSCs for cartilage regeneration, however, remains to be fully determined. This study has examined the chondrogenic potential of human STRO-1-immunoselected SSCs (STRO-1+ SSCs), in comparison to human articular chondrocytes (HACs), by utilising two bioengineering strategies, namely ‘‘scaffold-free’’ three-dimensional(3-D) pellet culture and culture using commercially available, highly porous, 3-D scaffolds with interconnected pore networks. STRO-1+ SSCs were isolated by magnetic-activated cell sorting from bone marrow samples of haematologically normal osteoarthritic individuals following routine hip replacement procedures. Chondrocytes were isolated by sequential enzymatic digestion of deep zone articular cartilage pieces dissected from femoral heads of the same individuals. After expansion in monolayer cultures, the harvested cell populations were centrifuged to form high-density 3-D pellets and also seeded in the 3-D scaffold membranes, followed by culture in serum-free chondrogenic media under static conditions for 21 and 28 days, respectively. Chondrogenic differentiation was determined by gene expression,histological and immunohistochemical analyses. Robust cartilage formation and expression of hyaline cartilage-specific markers were observed in both day-21 pellets and day-28 explants generated using HACs. In comparison, STRO-1+ SSCs demonstrated significantly lower chondrogenic differentiation potential and a tendency for hypertrophic differentiation in day-21 pellets. Culture of STRO-1+ SSCs in the 3-D scaffolds improved the expression of hyaline cartilage-specific markers in day-28 explants, however, was unable to prevent hypertrophic differentiation of the SSC population. The advantages of application of SSCs in tissue engineering are widely recognised; the results of this study, however, highlight the need for further development of cell culture protocols that may otherwise limit the application of this stem cell population in cartilage bioengineering strategies
Low-Jitter Clock Multiplication: a Comparioson between PLLs and DLLs
This paper shows that, for a given power budget, a practical phase-locked loop (PLL)-based clock multiplier generates less jitter than a delay-locked loop (DLL) equivalent. This is due to the fact that the delay cells in a PLL ring-oscillator can consume more power per cell than their counterparts in the DLL. We can show that this effect is stronger than the notorious jitter accumulation effect that occurs in the voltage-controlled oscillator (VCO) of a PLL. First, an analysis of the stochastic-output jitter of the architectures, due to the most important noise sources, is presented. Then, another important source of jitter in a DLL-based clock multiplier is treated, namely the stochastic mismatch in the delay cells which compose the DLL voltage-controlled delay line (VCDL). An analysis is presented that relates the stochastic spread of the delay of the cells to the output jitter of the clock multiplier. A circuit design technique, called impedance level scaling, is then presented which allows the designer to optimize the noise and mismatch behavior of a circuit, independently from other specifications such as speed and linearity. Applying this technique on a delay cell design yields a direct tradeoff between noise induced jitter and power usage, and between stochastic mismatch induced jitter and power usage
Rational design and dynamics of self-propelled colloidal bead chains: from rotators to flagella
The quest for designing new self-propelled colloids is fuelled by the demand
for simple experimental models to study the collective behaviour of their more
complex natural counterparts. Most synthetic self-propelled particles move by
converting the input energy into translational motion. In this work we address
the question if simple self-propelled spheres can assemble into more complex
structures that exhibit rotational motion, possibly coupled with translational
motion as in flagella. We exploit a combination of induced dipolar interactions
and a bonding step to create permanent linear bead chains, composed of
self-propelled Janus spheres, with a well-controlled internal structure. Next,
we study how flexibility between individual swimmers in a chain can affect its
swimming behaviour. Permanent rigid chains showed only active rotational or
spinning motion, whereas longer semi-flexible chains showed both translational
and rotational motion resembling flagella like-motion, in the presence of the
fuel. Moreover, we are able to reproduce our experimental results using
numerical calculations with a minimal model, which includes full hydrodynamic
interactions with the fluid. Our method is general and opens a new way to
design novel self-propelled colloids with complex swimming behaviours, using
different complex starting building blocks in combination with the flexibility
between them.Comment: 27 pages, 10 figure
Pola Asuh Orangtua Pada Anak Tuna Rungu Di Kelurahan Sail Kecamatan Tenayan Raya
This research was conducted in Kelurahan Sail Tenayan Raya District. This study clims to know the prential care patterns in Kelurahan Sail Tenayan Raya District was eximined by qualitative descriptive analysis. In this study, the writer collected the data by direct interview technique in research location. The responden in this study amount 7 people, namely 5 the mother of the deaf children, a teacher and a doctor. The instruments used in this study are the questions as interview materials, photos and video recording too. The result of this study indicate that the parenting tendenas applied by parent to deaf children is permissive, which provide loose supervision to the children to something without adequate supervision from their parents. The parenting implemented through family function. The deafness which is happened by children make the parents difficullty for keeping even communicating with the deaf children. The deaf children use sign language and action as a communication between parent and other peolple around them. The role of teachers in the school is that continue to educate children, shaping the character, the child personality and improve the language or intellectual ability of the child. The role of doctors is very important in the people handlig with hearing impairment including children who are deafned. Doctors play a role in dealing with deaf children
Functional Architecture for Disparity in Macaque Inferior Temporal Cortex and Its Relationship to the Architecture for Faces, Color, Scenes, and Visual Field
Binocular disparity is a powerful depth cue for object perception. The computations for object vision culminate in inferior temporal cortex (IT), but the functional organization for disparity in IT is unknown. Here we addressed this question by measuring fMRI responses in alert monkeys to stimuli that appeared in front of (near), behind (far), or at the fixation plane. We discovered three regions that showed preferential responses for near and far stimuli, relative to zero-disparity stimuli at the fixation plane. These “near/far” disparity-biased regions were located within dorsal IT, as predicted by microelectrode studies, and on the posterior inferotemporal gyrus. In a second analysis, we instead compared responses to near stimuli with responses to far stimuli and discovered a separate network of “near” disparity-biased regions that extended along the crest of the superior temporal sulcus. We also measured in the same animals fMRI responses to faces, scenes, color, and checkerboard annuli at different visual field eccentricities. Disparity-biased regions defined in either analysis did not show a color bias, suggesting that disparity and color contribute to different computations within IT. Scene-biased regions responded preferentially to near and far stimuli (compared with stimuli without disparity) and had a peripheral visual field bias, whereas face patches had a marked near bias and a central visual field bias. These results support the idea that IT is organized by a coarse eccentricity map, and show that disparity likely contributes to computations associated with both central (face processing) and peripheral (scene processing) visual field biases, but likely does not contribute much to computations within IT that are implicated in processing color.National Institutes of Health (U.S.) (Grant EY023322)National Science Foundation (U.S.) (Grant 1353571
PHYSICAL EDUCATION AS A MEDIUM TO MENTALLY RETARDED STUDENTS’ SELF DEVELOPMENTS
This study aims to (1) Obtain the phenomenon overview of mentally retarded students in everyday life. (2) Determine the motion behaviors of mentally retarded students outside and inside physical education activities. (3) Figure out the mentally retarded students’ ability in joining the activities of physical education and any obstacles faced by them. (4) Figure out how teachers give the treatments to mentally retarded students while they are doing sports activities in physical education. (5) Figure out the activities of physical education for students’ self-developments. Subject of this research are mentally retarded students at Special Education School with Multiple Disabilities of Bina Sejahtera Surakarta. This study was using qualitative methods Life story-Case Study with four criteria used; the degree of confidence (credibility), transferability, dependability, and certainty (conformability). The degree of confidence was examined by using triangulation of data from the informant who was considered as a person who was close enough to the mentally retarded students. The analysis in this study was carried out within five stages, namely: (1) data reduction, (2) data display, (3) conclusion drawing, (4) results validity enhancement and (5) narrative analysis results. The results of this research show that physical education can be a medium for mentally retarded students’ personal development, which includes some aspects of them, such as; physical education is proven to enhance the students’ concentrations and focuses, increase their self-confidences and physical activities can help students to interact socially well and improve their self-developments. Article visualizations
Identifying and Imposing Partial Equilibrium in Chemically Reacting Systems
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/76236/1/AIAA-2003-667-389.pd
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