Link layer multi-priority frame forwarding

With increasing demand for multimedia and real-time applications, local area network (LAN) technologies are rapidly being upgraded to support Quality-of-Service (QoS). Many QoS-enabled LANs are making use of resource allocation mechanisms that can discriminate among traffic classes of different priorities. When such LANs are interconnected by bridges to form an extended LAN, it is necessary to upgrade the bridges so that they are QoS-enabled as well. For example, the IEEE 802.1p standard defines a framework for priority queuing in bridges. Alternatively, frame forwarding decisions at the link layer may be modified to recognize frame priorities and alternate paths may be used for differentiating QoS. In this paper, we describe a novel bridge protocol that can forward frames of different priorities using different paths. Our protocol ensures that the forwarding path of a higher priority frame is never longer than the forwarding path of a lower priority frame.published_or_final_versio

Some scheduling problems with deteriorating jobs and learning effects

Author name used in this publication: T. C. E. Cheng2007-2008 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

The androgen receptor and signal-transduction pathways in hormone-refractory prostate cancer. Part 2: androgen-receptor cofactors and bypass pathways

Prostate cancer is the second leading cause of cancer related deaths in men from the western world. Treatment of prostate cancer has relied on androgen deprivation therapy for the past 50 years. Response rates are initially high (70-80%), however almost all patients develop androgen escape and subsequently die within 1-2 years. Unlike breast cancer, alternative approaches (chemotherapy and radiotherapy) do not increase survival time. The high rate of prostate cancer mortality is therefore strongly linked to both development of androgen escape and the lack of alternate therapies. AR mutations and amplifications can not explain all cases of androgen escape and post-translational modification of the AR has become an alternative theory. However recently it has been suggested that AR co-activators e.g. SRC-1 or pathways the bypass the AR (Ras/MAP kinase or PI3K/Akt) may stimulated prostate cancer progression independent of the AR. This review will focus on how AR coactivators may act to increase AR transactivation during sub-optimal DHT concentrations and also how signal transduction pathways may promote androgen escape via activation of transcription factors, e.g. AP-1, c-Myc and Myb, that induce cell proliferation or inhibit apoptosis

Higher dementia incidence in older adults with type 2 diabetes and large reduction in HbA1c

BACKGROUND: although type 2 diabetes increases risk of dementia by 2-fold, whether optimizing glycemic level in late life can reduce risk of dementia remains uncertain. We examined if achieving the glycemic goal recommended by the American Diabetes Association (ADA) within a year was associated with lower risk of dementia in 6 years. METHODS: in this population-based observational study, we examined 2246 community-living dementia-free Chinese older adults with type 2 diabetes who attended the Elderly Health Centres in Hong Kong at baseline and followed their HbA1c level and cognitive status for 6 years. In line with the ADA recommendation, we defined the glycemic goal as HbA1c < 7.5%. The study outcome was incident dementia in 6 years, diagnosed according to the 10th revision of the International Statistical Classification of Diseases and Related Health Problems (ICD-10) or Clinical Dementia Rating of 1-3. RESULTS: those with HbA1c ≥ 7.5% at baseline and HbA1c < 7.5% in 1 year were associated with higher rather than lower incidence of dementia, independent of severe hypoglycemia, glycemic variability and other health factors. Sensitivity analyses showed that a relative reduction of ≥10%, but not 5-10%, in HbA1c within a year was associated with higher incidence of dementia in those with high (≥8%) and moderate (6.5-7.9%) HbA1c at baseline. CONCLUSION: a large reduction in HbA1c could be a potential predictor and possibly a risk factor for dementia in older adults with type 2 diabetes. Our findings suggest that optimizing or intensifying glycemic control in this population requires caution

A comparison of the in- and out-patient referral patterns of four tertiary rheumatology centres in Beijing, Hong Kong, Kaohsiung and Los Angeles

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