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This article shares findings from evaluating a mentoring programme for Aboriginal youth on Yorta Yorta (an Aboriginal Tribal nation, north-eastern Victoria and Southern New South Wales, Australia) Country. This work is positioned in First Nations worldviews that are relational and require deep listening to youth, mentors, Elders, Country, and Ancestors. Applying a qualitative participatory action research design, methods involved attending camps on Country and research Yarning Circles. The findings demonstrate that Aboriginal mentoring programmes need to be led in their delivery and evaluation by First Nations peoples. This ensures that the programmes are culturally embedded in First Nations worldviews and that important interpretations of meanings are not overlooked. On Country experiences are a place for healing and learning. Country is a stakeholder in Aboriginal mentoring programmes. A trusting mentoring relationship creates a space where youth become part of an Aboriginal community, and where they feel strong in their identity.

Reliability at massive scale is one of the biggest challenges we face at Amazon.com, one of the largest e-commerce operations in the world; even the slightest outage has significant financial consequences and impacts customer trust. The Amazon.com platform, which provides services for many web sites worldwide, is implemented on top of an infrastructure of tens of thousands of servers and network components located in many datacenters around the world. At this scale, small and large components fail continuously and the way persistent state is managed in the face of these failures drives the reliability and scalability of the software systems. This paper presents the design and implementation of Dynamo, a highly available key-value storage system that some of Amazon's core services use to provide an "always-on" experience. To achieve this level of availability, Dynamo sacrifices consistency under certain failure scenarios. It makes extensive use of object versioning and application-assisted conflict resolution in a manner that provides a novel interface for developers to use.

Imaging studies of conscious perception using techniques such as masking often show increased neural responses in object processing regions of the brain, and accompany increased awareness of the stimulus. Imaging studies of the attentional blink, an effect where conscious awareness of the stimulus is suppressed through reduction of attentional resources, has tended to show the opposite neural response. This study examines changes in stimulus parameters such that either attention or perceptual information is limited. Findings show that under conditions of limited attention but reduced perception the BOLD response reveals increased activity when the stimulus cannot be reported; however, under conditions of reduced perception but normal attention, more activity is revealed on trials when the stimulus can be reported.

Presenting two targets for identification within a few hundred milliseconds reliably yields reduced performance on the second relative to the first. This attentional blink phenomenon has been extensively studied behaviourally but, until recently, has eluded direct investigation by functional magnetic resonance imaging. The few published imaging studies agree that the attentional blink recruits a fronto-temporo-parietal ‘attentional’ network. What remains controversial is the specific role played by the ‘object processing’ ventro-occipital regions of the brain. Two studies used different tasks and stimulus onset asynchronies leaving the cause for this divergence unknown. The present study resolves this discrepancy by examining the different methodologies. Our results suggest that task difficulty and masking must be factored in to any conclusions drawn about the brain activity during the attentional blink paradigm.

The dramatic growth of distributed computing applications is creating both an opportunity and a daunting challenge for users seeking to build applications that will play critical roles in their organization. Here, we discuss the use of a new system, Astrolabe, to automate self-configuration, monitoring, and to control adaptation. Astrolabe operates by creating a virtual system-wide hierarchical database, which evolves as the underlying information changes. Astrolabe is secure, robust under a wide range of failure and attack scenarios, and imposes low loads even under stress. To focus the discussion, we structure it around a hypothetical Web Services scenario. One of the major opportunities created by Astrolabe is to allow Web Services client systems to autonomically adapt when a data center becomes slow or unreachable.The dramatic growth of distributed computing applications is creating both an opportunity and a daunting challenge for users seeking to build applications that will play critical roles in their organization. Here, we discuss the use of a new system, Astrolabe, to automate self-configuration, monitoring, and to control adaptation. Astrolabe operates by creating a virtual system-wide hierarchical database, which evolves as the underlying information changes. Astrolabe is secure, robust under a wide range of failure and attack scenarios, and imposes low loads even under stress. To focus the discussion, we structure it around a hypothetical Web Services scenario. One of the major opportunities created by Astrolabe is to allow Web Services client systems to autonomically adapt when a data center becomes slow or unreachable.

Building very large computing systems is extremely challenging, given the lack of robust scalable communication technologies. This threatens a new generation of mission-critical but very large computing systems. Fortunately, a new generation of "gossip-based" or epidemic communication primitives can overcome a number of these scalability problems, offering robustness and reliability even in the most demanding settings. Epidemic protocols emulate the spread of an infection in a crowded population, and are both reliable and stable under forms of stress that will disable most traditional protocols. This paper describes some of the common problems that arise in scalable group communication systems and how epidemic techniques have been used to successfully address these problems.