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1.
D. Rossi M. Omaña J. M. Cazeaux C. Metra T. M. Mak 《Journal of Electronic Testing》2014,30(1):111-123
In this paper, we show that clock faults producing duty-cycle variations, which have been proven very likely, can give rise to min or max delay violations. This mandates new, specific testing approaches for clock faults, to avoid them to compromise the system correct operation in the field, with dramatic effects on product quality and defect level. We then introduce a new scheme that can be employed to detect the clock faults causing duty-cycle variations. 相似文献
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Systemic lupus erythematosus (SLE) is an immune-complex-mediated multi-systemic autoimmune condition of multifactorial etiology, which mainly affects young women. It is currently believed that the onset of SLE and lupus flares are triggered by various environmental factors in genetically susceptible individuals. Various environmental agents and toxicants, such as cigarette smoke, alcohol, occupationally- and non-occupationally-related chemicals, ultraviolet light, infections, sex hormones and certain medications and vaccines, have been implicated to induce SLE onset or flares in a number case series, case-control and population-based cohort studies and very few randomized controlled trials. Here, we will describe some of these recognized environmental lupus triggering and perpetuating factors and explain how these factors potentially bias the immune system towards autoimmunity through their interactions with genetic and epigenetic alterations. Further in-depth exploration of how potentially important environmental factors mechanistically interact with the immune system and the genome, which trigger the onset of SLE and lupus flares, will certainly be one of the plausible steps to prevent the onset and to decelerate the progress of the disease. 相似文献
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Sau-Wa Mak 《Food and Foodways: Explorations in the History and Culture of》2014,22(4):322-347
This article provides an ethnography and analysis of the revival of the tradition of indigenous water buffalo cheese and milk product consumption in Shunde, Guangdong. Contrary to the widely held belief that dairy products are not part of the traditional Chinese diet, water buffalo cheese and milk products have been part of the food systems of Guangdong for centuries. But in the past 30 years, these indigenous milk products have been reinvented as a kind of culinary heritage, supplemented by new forms and practices. The popularity of water buffalo milk products in Shunde today has come about as a result of marketing by various agents, including cheese makers, milk merchants, chefs and the government in post-Mao China. Furthermore, the culture of milk consumption in Shunde today has been shaped by both the forces of post-reform economic development, international cultural institutions, the changing perceptions of members of different social classes, and modernity. The reinvented tradition of milk products provides people of different social classes with new ways of consuming milk products and of conducting social interactions. 相似文献
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Porous Coordination Polymers: Unveiling the Mechanism of Water‐Triggered Diplex Transformation and Correlating the Changes in Structures and Separation Properties (Adv. Funct. Mater. 41/2015) 下载免费PDF全文
Li‐Hui Cao Yong‐Sheng Wei Hong Xu Shuang‐Quan Zang Thomas C. W. Mak 《Advanced functional materials》2015,25(41):6556-6556
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Most research on natural fiber composites has been primarily conducted on randomly‐oriented fibers. This study is focused on the short‐ and long‐term performances of flax fiber‐reinforced polymer (Flax‐FRP) made from continuous unidirectional fiber mats, and compares it to Glass‐FRP composite. The study looked into the effect of number of layers on properties, comparing wet layup (WL) to vacuum bag (VB) molding, and aging in a 3.5% salt solution for up to 365 days at 23, 40, and 55°C. Results show that Flax‐FRP has a tensile strength and modulus of one third the values of Glass‐FRP. Using the VB process, Flax‐FRP showed a strength and modulus 18 and 36% higher, respectively, than WL specimens. As the number of layers increased from one to five, the strength and modulus also increased but stabilized at three layers. After 365 days of conditioning at 23, 40, and 55°C, WL specimens showed a strength retention of 81, 73, and 69%, respectively. Using the Arrhenius relationship, it was estimated that both WL and VB Flax‐FRP would retain 60% of their tensile strength after 100 years of saltwater exposure at an annual mean temperature of 10°C. POLYM. COMPOS., 37:3234–3244, 2016. © 2015 Society of Plastics Engineers 相似文献
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Oi Wei Mak Nursyafikah Seman Nor Hamizah Harun Rusnah Syahila Duali Hussen Nasrulzamani Mohd Rodzi Thorsten Heidelberg 《Journal of surfactants and detergents》2015,18(6):973-980
A biantennary surfactant based on a synthetic C16‐maltoside was chosen to prepare vesicles for a potential vesicular drug delivery system. The synthesis comprised of three stages: Initial synthesis of β‐d ‐maltose octaacetate was followed by glycosidation of 2‐hexyl‐decanol and final glycolipid deacetylation. Both α‐ and β‐anomers were prepared and their anomeric purity was evaluated by 1H NMR. Owing to the low water solubility of the glycolipid, addition of ionic co‐surfactants was believed to promote the surfactant distribution, thus leading to smaller and more uniform vesicles. The assembly behavior of the surfactant systems was studied by contact penetration under an optical polarizing microscope, while interfacial properties were determined by surface tension measurements. Vesicles were prepared by injection of an ethanolic solution into bulk water and investigated by dynamic light scattering and field emission scanning electron microscopy. Contact of the surfactant mixtures with water indicated a high tendency to exhibit the lamellar phase and confirmed the expected low molecular solubility. These findings suggest a potential of the surfactant to form stable vesicles. Injection of an ethanolic surfactant solution into bulk water gave sub‐micrometer sized vesicles with a narrow size distribution. Application of ionic co‐surfactants reduced the vesicle size. In particular ~20 % of anionic SDS proved highly effective, lowering the vesicle size by nearly one decade, thus accessing nano‐sized vesicles. Encapsulation of a water‐soluble drug was achieved in a 76 ± 10 % efficiency. 相似文献
9.
Siping Zhou Bevis W. L. Mak Echo Leong Kan Hon-Shing Ip Shu-kuen Liu Tze-Kwan 《Water and Environment Journal》2010,24(2):140-146
Stability of sludge blanket is a critical factor controlling the performance of clarifiers. A three-dimensional computational fluid dynamics (CFD) model was applied to optimize the clarifier design at the Tai Po Sewage Treatment Works, Hong Kong. Validated by field data, the CFD model evaluated the key clarifier design elements including side-water depth, centre-feed inlet, flocculation well and returned activated sludge (RAS) flow. Based on field observations and modelling results, the new design aims at eliminating the strong turbulence typical of centre-feed inlets in the clarifier, thus creating a better flocculation environment, and reducing disturbance to the sludge blanket. The modelling results also demonstrated a marked improvement in clarifier performance after the increase in clarifier depth and hence sludge storage capacity. The increased storage capacity reduces the risk of high sludge blanket levels upsetting the clarified effluent quality under high flow or solids loading conditions. 相似文献
10.
Ka-Meng Lei Pui-In Mak Rui P. Martins 《Analog Integrated Circuits and Signal Processing》2013,77(2):277-284
A dynamic latched comparator can suffer from three non-idealities: offset voltage, random noise and kickback noise. Specifically in an analog-to-digital converter (ADC) the kickback noise of a comparator can noticeably affect the settling time and accuracy of the decision. This work offers an analytical treatment of kickback noise generation, and proposes a synchronized kickback noise cancellation technique, which is achieved via placing clocked NMOS-PMOS capacitors at the proper nodes to cancel out effectively those unwanted charges (electrons or holes) under different operating regions of the MOS devices. The technique is clock-rate insensitive and particularly suitable for the SAR-type ADC as it will not alter the charge stored in the capacitor array. Optimized in 65-nm CMOS the kickback noise is <±0.3 mV in 30× Monte–Carlo simulations at both 50- and 500-MHz clock rates. For 10-bit resolution in a full scale of 1 Vpp, the kickback noise of the proposed comparator comparing with the conventional one is improved by 48×, from 6.27 to 0.13 LSB. 相似文献