On the twentieth anniversary of the original publication [10], following ten years of intense activity in the research literature, hardware support for transactional memory (TM) has finally become a commercial reality, with HTM-enabled chips currently or soon-to-be available from many hardware vendors. In this paper we describe architectural support for TM added to a future version of the Power ISA™. Two imperatives drove the development: the desire to complement our weakly-consistent memory model with a more friendly interface to simplify the development and porting of multithreaded applications, and the need for robustness beyond that of some early implementations. In the process of commercializing the feature, we had to resolve some previously unexplored interactions between TM and existing features of the ISA, for example translation shootdown, interrupt handling, atomic read-modify-write primitives, and our weakly consistent memory model. We describe these interactions, the overall architecture, and discuss the motivation and rationale for our choices of architectural semantics, beyond what is typically found in reference manuals.

Shared memory concurrency relies on synchronisation primitives: compare-and-swap, load-reserve/store-conditional (aka LL/SC), language-level mutexes, and so on. In a sequentially consistent setting, or even in the TSO setting of x86 and Sparc, these have well-understood semantics. But in the very relaxed settings of IBM (R) POWER (R), ARM, or C/C++, it remains surprisingly unclear exactly what the programmer can depend on. This paper studies relaxed-memory synchronisation. On the hardware side, we give a clear semantic characterisation of the load-reserve/store-conditional primitives as provided by POWER multiprocessors, for the first time since they were introduced 20 years ago; we cover their interaction with relaxed loads, stores, barriers, and dependencies. Our model, while not officially sanctioned by the vendor, is validated by extensive testing, comparing actual implementation behaviour against an oracle generated from the model, and by detailed discussion with IBM staff. We believe the ARM semantics to be similar. On the software side, we prove sound a proposed compilation scheme of the C/C++ synchronisation constructs to POWER, including C/C++ spinlock mutexes, fences, and read-modify-write operations, together with the simpler atomic operations for which soundness is already known from our previous work; this is a first step in verifying concurrent algorithms that use load-reserve/store-conditional with respect to a realistic semantics. We also build confidence in the C/C++ model in its own terms, fixing some omissions and contributing to the C standards committee adoption of the C++11 concurrency model.

The growing complexity of hardware optimizations employed by multiprocessors leads to subtle distinctions among allowed and disallowed behaviors, posing challenges in specifying their memory models formally and accurately, and in understanding and analyzing the behavior of concurrent software. This complexity is particularly evident in the IBM® Power Architecture®, for which a faithful specification was published only in 2011 using an operational style. In this paper we present an equivalent axiomatic specification, which is more abstract and concise. Although not officially sanctioned by the vendor, our results indicate that this axiomatic specification provides a reasonable basis for reasoning about current IBM® POWER® multiprocessors. We establish the equivalence of the axiomatic and operational specifications using both manual proof and extensive testing. To demonstrate that the constraint-based style of axiomatic specification is more amenable to computer-aided verification, we develop a SAT-based tool for evaluating possible outcomes of multi-threaded test programs, and we show that this tool is significantly more efficient than a tool based on an operational specification.

Shared memory concurrency relies on synchronisation primitives: compare-and-swap, load-reserve/store-conditional (aka LL/SC), language-level mutexes, and so on. In a sequentially consistent setting, or even in the TSO setting of x86 and Sparc, these have well-understood semantics. But in the very relaxed settings of IBM®, POWER®, ARM, or C/C++, it remains surprisingly unclear exactly what the programmer can depend on. This paper studies relaxed-memory synchronisation. On the hardware side, we give a clear semantic characterisation of the load-reserve/store-conditional primitives as provided by POWER multiprocessors, for the first time since they were introduced 20 years ago; we cover their interaction with relaxed loads, stores, barriers, and dependencies. Our model, while not officially sanctioned by the vendor, is validated by extensive testing, comparing actual implementation behaviour against an oracle generated from the model, and by detailed discussion with IBM staff. We believe the ARM semantics to be similar. On the software side, we prove sound a proposed compilation scheme of the C/C++ synchronisation constructs to POWER, including C/C++ spinlock mutexes, fences, and read-modify-write operations, together with the simpler atomic operations for which soundness is already known from our previous work; this is a first step in verifying concurrent algorithms that use load-reserve/store-conditional with respect to a realistic semantics. We also build confidence in the C/C++ model in its own terms, fixing some omissions and contributing to the C standards committee adoption of the C++11 concurrency model.

Background: Trauma is the leading cause of death in children, accounting for half of all deaths in patients between birth and 18 years of age, and is the cause of a significant number of hospital admissions. We reviewed our experience at a Level I pediatric trauma center with a 2-level trauma activation (TA) system for mobilization of personnel over a 3-year period. The aim was to assess severity of injury of the trauma patients, resource use, and outcome.Methods: After obtaining institutional review board approval, a retrospective analysis of all trauma patients between January 2006 and December 2008 was performed. Data analyzed included number of admissions, level of TA (STAT vs ALERT), mechanism of injury, intensive care unit (ICU) admission, injury severity score (ISS), need for operative intervention, and survival.Results: In 3 years, there were 4502 patients entered. Trauma activation was initiated in 1315 patients (29.2%), divided between 211 STATs (4.7%) and 1104 ALERTs (24.5%). Mean patient age was 5.9 +/- 4.1 years, 65% of the patients were boys, and blunt trauma accounted for 92% of the admissions. An ICU admission was required in 736 (16.3%) of the entire group, whereas 502 (38.2%) patients in the TA group were admitted to the ICU(1). The 154 STAT (21%) and 348 ALERT (47%) patients accounted for 68% of all ICU admissions(1). An ISS listed as severe (16-24) or very severe (>24) was found in 468 (10.4%) and 232 (5.2%) patients, respectively. An ISS listed as 16 or higher was found in 144 (68.2%) of the STATs and 264 (23.9%) of the ALERTs(1). Operative intervention was required in 2118 patients (47%). The overall mortality rate was 1.9%, and this increased to 5.8% in the TA group(1). There were 48 deaths (22.7%) in the STAT group, 29 deaths (2.6%) in the ALERT group, and 9 deaths (0.28%) in patients with no TA(1). When emergency department deaths were excluded, the remaining 60 deaths resulted in a mortality rate of 1.3%.Conclusions: Our Level I pediatric trauma center manages a large volume of patients with significant acuity and, evidenced by a TA in 29% of the patients, a severe or very severe ISS in 16% of the patients, 16% of the patients requiring ICU admission, and 47% requiring operative intervention. The TA patients had markedly higher rates of ICU admission, ISS, and mortality. Deaths in the study were lower by almost an order of magnitude comparing TA STATs with TA ALERTs and TA ALERT patients with patients without TA.The TA criteria are in many ways very helpful and is integral to a Level I trauma center. However, opportunities were identified for improvement because of areas of "overutilization" and discordance between TA and ISS. (C) 2011 Elsevier Inc. All rights reserved.

Exploiting today's multiprocessors requires high-performance and correct concurrent systems code (optimising compilers, language runtimes, OS kernels, etc.), which in turn requires a good understanding of the observable processor behaviour that can be relied on. Unfortunately this critical hardware/software interface is not at all clear for several current multiprocessors. In this paper we characterise the behaviour of IBM POWER multiprocessors, which have a subtle and highly relaxed memory model (ARM multiprocessors have a very similar architecture in this respect). We have conducted extensive experiments on several generations of processors: POWER G5, 5, 6, and 7. Based on these, on published details of the microarchitectures, and on discussions with IBM staff, we give an abstract-machine semantics that abstracts from most of the implementation detail but explains the behaviour of a range of subtle examples. Our semantics is explained in prose but defined in rigorous machine-processed mathematics; we also confirm that it captures the observable processor behaviour, or the architectural intent, for our examples with an executable checker. While not officially sanctioned by the vendor, we believe that this model gives a reasonable basis for reasoning about current POWER multiprocessors. Our work should bring new clarity to concurrent systems programming for these architectures, and is a necessary precondition for any analysis or verification. It should also inform the design of languages such as C and C++, where the language memory model is constrained by what can be efficiently compiled to such multiprocessors.

The software suite we will demonstrate at AAAI'06 was designed around planning with factored Markov decision processes (MDPs). It is a user-friendly suite that facilitates domain elicitation, preference elicitation, planning, and MDP policy display. The demo will concentrate on user interactions for domain experts and those for whom plans are made.

To examine the link between bone material properties and skeletal fragility, we analyzed the mechanical, histological, biochemical, and spectroscopic properties of bones from a murine model of skeletal fragility (SAMP6). Intact bones from SAMP6 mice are weak and brittle compared with SAMR1 controls, a defect attributed to reduced strength of the bone matrix. The matrix weakness is attributed primarily to poorer organization of collagen fibers and reduced collagen content.Introduction: The contribution of age-related changes in tissue material properties to skeletal fragility is poorly understood. We previously reported that bones from SAMP6 mice are weak and brittle versus age-matched controls. Our present objectives were to use the SAMP6 mouse to assess bone material properties in a model of skeletal fragility and to relate defects in the mechanical properties of bone to the properties of demineralized bone and to the structure and organization of collagen and mineral.Materials and Methods: Femora from 4- and 12-month-old SAMR1 (control) and SAMP6 mice were analyzed using bending and torsional mechanical testing of intact bones, tensile testing of demineralized bone, quantitative histology (including collagen fiber orientation), collagen cross-links biochemistry, and Raman spectroscopic analysis of mineral and collagen.Results: Intact bones from SAMP6 mice have normal elastic properties but inferior failure properties, with 60% lower fracture energy versus SAMR1 controls. The strength defect in SAMP6 bones was associated with a 23% reduction in demineralized bone strength, which in turn was associated with poorer collagen fiber organization, lower collagen content, and higher hydroxylysine levels. However, SAMP6 have normal levels of collagen cross-links and normal apatite mineral structure.Conclusions: Bones from SAMP6 osteoporotic mice are weak and brittle because of a defect in the strength of the bone matrix. This defect is attributed primarily to poorer organization of collagen fibers and reduced collagen content. These findings highlight the role of the collagen component of the bone matrix in influencing skeletal fragility.

UK hospitals have been instructed to ensure that all staff understand the institution's resuscitation policy. Using a questionnaire, we determined the level of knowledge about the hospital's 'do not attempt resuscitation' (DNAR) policy amongst a range of staff. Six hundred and seventy-seven questionnaires were returned. 91.4% of responders did not know the correct overall percentage survival to hospital discharge following an in-hospital cardiac arrest. 19.3% of doctors, 10.6% of nurses, and 8.9% of health care support workers (HCSW) gave answers in the correct range (i.e., 15-25%). Most doctors (93.5%), nurses (93.5%), and HCSW (78.9%) correctly identified that cardiopulmonary resuscitation (CPR) should be the default position, when a DNAR decision does not exist. The majority of doctors (78.5%), nurses (73.2%) and HCSW (65.8%) appreciated that the hospital policy allowed a senior trainee doctor (specialist registrar; SpR) to make the initial decision without consultation with more senior medical staff. Knowledge of who was ultimately responsible for the DNAR decision was also good, with 100% of doctors, 100% of midwives, 98.3% of nurses and 78.9% of HCSW responding correctly. Ten percent of doctors, 15% of nurses and 10.5% of HCSW believed that the next of kin could demand resuscitation or a DNAR status. There was inconsistency about what information staff felt should be included in DNAR documentation and what, if any, continuing care should be given to patients who are not for resuscitation. Our study demonstrates that there is room for improvement in the awareness of staff about the DNAR process. The local DNAR policy is being reviewed to ensure that its messages are clear and a specific DNAR educational programme has been commenced.

This article studies the efforts of the Ecuadorian government between 1861 and 1875 to construct a "truly catholic nation". It examines the implementation and engagement of centralized initiatives of morality and religiosity, and reflects on its implications for the repositioning of state-society boundaries. Specifically, it considers the government's efforts after 1869 to centrally coordinate the institutions of municipal government and Church, and to redeploy them for national moralizing ends. it assesses the substantial achievements and limits of this model for strengthening state power and for disseminating "national" meanings of citizenship and progress.

New Zealand GeographerVolume 47, Issue 1 p. 41-41 PREHISTORY IN THE PACIFIC ISLANDS DEREK WILLIAMS, DEREK WILLIAMS Department of Geography Massey UniversitySearch for more papers by this author DEREK WILLIAMS, DEREK WILLIAMS Department of Geography Massey UniversitySearch for more papers by this author First published: April 1991 https://doi.org/10.1111/j.1745-7939.1991.tb01986.xAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume47, Issue1April 1991Pages 41-41 RelatedInformation

Interview data from a two and a half year study of 20 District General Managers (DGMs) from a wide variety of backgrounds confirmed the view that there has been widespread dissatisfaction about the work of the District Medical Officer (DMO). This dissatisfaction was often mirrored by the DMOs themselves. We therefore supplemented the interviews with a questionnaire listing 16 principal functions of community medicine and asked the DGMs and their DMOs independently to rate the amount of attention devoted by the DMO to each function both currently and ideally. We found a contrast between the overall uncertainty and concern expressed about community medicine during discussions, and the enthusiasm for the itemized community medical functions. There was close correlation between the DGMs' and DMOs' mean rates, which were always higher in the ideal than the current rating, and particularly so for the DMO's work in information and assessment of need, in service evaluation, and — only among the DMOs' responses — in the independent advocacy of public health. We present the detailed results for all the functions, and discuss the implications of these and our interview data for the implementation of the Acheson Report and for the managerial education of public health physicians.

Journal of Management StudiesVolume 6, Issue 3 p. 346-365 USES OF ROLE THEORY IN MANAGEMENT AND SUPERVISORY TRAINING Derek Williams, Derek WilliamsSearch for more papers by this author Derek Williams, Derek WilliamsSearch for more papers by this author First published: October 1969 https://doi.org/10.1111/j.1467-6486.1969.tb00602.xCitations: 3Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat Citing Literature Volume6, Issue3October 1969Pages 346-365 RelatedInformation