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Significance\ud \ud Communicating in ways that motivate engagement in social distancing remains a critical global public health priority during the COVID-19 pandemic. This study tested motivational qualities of messages about social distancing (those that promoted choice and agency vs. those that were forceful and shaming) in 25,718 people in 89 countries. The autonomy-supportive message decreased feelings of defying social distancing recommendations relative to the controlling message, and the controlling message increased controlled motivation, a less effective form of motivation, relative to no message. Message type did not impact intentions to socially distance, but people’s existing motivations were related to intentions. Findings were generalizable across a geographically diverse sample and may inform public health communication strategies in this and future global health emergencies.\ud \ud \ud \ud Abstract\ud \ud Finding communication strategies that effectively motivate social distancing continues to be a global public health priority during the COVID-19 pandemic. This cross-country, preregistered experiment (n = 25,718 from 89 countries) tested hypotheses concerning generalizable positive and negative outcomes of social distancing messages that promoted personal agency and reflective choices (i.e., an autonomy-supportive message) or were restrictive and shaming (i.e., a controlling message) compared with no message at all. Results partially supported experimental hypotheses in that the controlling message increased controlled motivation (a poorly internalized form of motivation relying on shame, guilt, and fear of social consequences) relative to no message. On the other hand, the autonomy-supportive message lowered feelings of defiance compared with the controlling message, but the controlling message did not differ from receiving no message at all. Unexpectedly, messages did not influence autonomous motivation (a highly internalized form of motivation relying on one’s core values) or behavioral intentions. Results supported hypothesized associations between people’s existing autonomous and controlled motivations and self-reported behavioral intentions to engage in social distancing. Controlled motivation was associated with more defiance and less long-term behavioral intention to engage in social distancing, whereas autonomous motivation was associated with less defiance and more short- and long-term intentions to social distance. Overall, this work highlights the potential harm of using shaming and pressuring language in public health communication, with implications for the current and future global health challenges.

The goal of this project was to scan and reverse engineer one of three bronze cannons (41MG86 - 11900-1) recovered from the La Belle excavation, which is currently on exhibit at the Bullock Texas State History Museum in Austin, Texas. A freeform computer aided design (CAD) model was generated based upon the topology of the three-dimensional (3-D) mesh in Geomagic Design X with a desired maximum deviation of 0.1 mm between the model and the mesh. Deviations were calculated in Geomagic Control X using the surface model as the reference data, and the mesh as the measured data. A custom patch network was subsequently designed using a series of iterative revisions until the whole of the surface model met with the specified tolerance. The 3-D surface model of the cannon will be replicated in a variety of media at variable scales for use in exhibits and for educational and promotional material for the Texas Historical Commission, the Republic of France, and their partner museums.

Graph applications are common in scientific and enterprise computing. Recent research used graphics processing units (GPUs) to accelerate graph workloads. These applications tend to present characteristics that are challenging for SIMD execution. To achieve high performance, prior work studied individual graph problems, and designed device-specific algorithms and optimizations to achieve high performance. However, programmers have to expend significant manual effort, packing data and computation to make such solutions GPU-friendly. This usually is too complex for regular programmers, and the resultant implementations may not be portable and perform well across platforms. To address these concerns, we propose and implement a library of software building blocks with application examples, BelRed which allows programmers to build graph applications with ease. BelRed currently is built on top of the OpenCL™ framework and optimized for GPUs. It consists of fundamental linear-algebra building blocks necessary for graph processing. Developers can program graph algorithms with a set of key primitives. This paper introduces the API and presents several case studies on how to use the library for a variety of representative graph problems. We evaluate application performance on an AMD GPU and investigate optimization techniques to improve performance. We show that this framework is useful to provide satisfactory GPU acceleration of various graph applications and help reduce programming efforts significantly.

Modern accelerator programming frameworks, such as OpenCL, organise threads into work-groups. Remote-scope promotion (RSP) is a language extension recently proposed by AMD researchers that is designed to enable applications, for the first time, both to optimise for the common case of intra-work-group communication (using memory scopes to provide consistency only within a work-group) and to allow occasional inter-work-group communication (as required, for instance, to support the popular load-balancing idiom of work stealing). We present the first formal, axiomatic memory model of OpenCL extended with RSP. We have extended the Herd memory model simulator with support for OpenCL kernels that exploit RSP, and used it to discover bugs in several litmus tests and a work-stealing queue, that have been used previously in the study of RSP. We have also formalised the proposed GPU implementation of RSP. The formalisation process allowed us to identify bugs in the description of RSP that could result in well-synchronised programs experiencing memory inconsistencies. We present and prove sound a new implementation of RSP that incorporates bug fixes and requires less non-standard hardware than the original implementation. This work, a collaboration between academia and industry, clearly demonstrates how, when designing hardware support for a new concurrent language feature, the early application of formal tools and techniques can help to prevent errors, such as those we have found, from making it into silicon.

This article provides an overview of AMD's vision for exascale computing, and in particular, how heterogeneity will play a central role in realizing this vision. Exascale computing requires high levels of performance capabilities while staying within stringent power budgets. Using hardware optimized for specific functions is much more energy efficient than implementing those functions with general-purpose cores. However, there is a strong desire for supercomputer customers not to have to pay for custom components designed only for high-end high-performance computing systems. Therefore, high-volume GPU technology becomes a natural choice for energy-efficient data-parallel computing. To fully realize the GPU's capabilities, the authors envision exascale computing nodes that compose integrated CPUs and GPUs (that is, accelerated processing units), along with the hardware and software support to enable scientists to effectively run their scientific experiments on an exascale system. The authors discuss the hardware and software challenges in building a heterogeneous exascale system and describe ongoing research efforts at AMD to realize their exascale vision.

Current trends suggest that future computing platforms will be increasingly heterogeneous. While these heterogeneous processors physically integrate disparate computing elements like CPUs and GPUs on a single chip, their programmability critically depends upon the ability to efficiently support cache coherence and shared virtual memory across tightly-integrated CPUs and GPUs. However, throughput-oriented GPUs easily overwhelm existing hardware coherence mechanisms that long kept the cache hierarchies in multi-core CPUs coherent. This paper proposes a novel solution called Software Assisted Hardware Coherence (SAHC) to scale cache coherence to future heterogeneous processors. We observe that the system software (Operating system and runtime) often has semantic knowledge about sharing patterns of data across the CPU and the GPU. This high-level knowledge can be utilized to effectively provide cache coherence across throughput-oriented GPUs and latency-sensitive CPUs in a heterogeneous processor. SAHC thus proposes a hybrid software-hardware mechanism that judiciously uses hardware coherence only when needed while using software's knowledge to filter out most of the unnecessary coherence traffic. Our evaluation suggests that SAHC can often eliminate up to 98-100% of the hardware coherence lookups, resulting up to 49% reduction in runtime.

Graph applications are common in scientific and enterprise computing. Recent research studies used graphics processing units (GPUs) to accelerate graph workloads. These applications tend to present characteristics that are challenging for single instruction multiple data (SIMD) computation. To achieve high performance, prior work studied individual graph problems, and designed device-specific algorithms and optimizations to achieve high performance. However, programmers have to expend significant manual effort, packing data and computation to make such solutions GPU-friendly. Usually, they are too complex for regular programmers, and the resultant implementations may not be portable nor perform well across platforms. To address these concerns, we present a library of software building blocks, BelRed1 which allows programmers to build GPGPU graph applications with ease. BelRed is based on the prior research of graph algorithms in linear algebra, and is implemented and optimized for the GPU platform. BelRed currently is built on top of the OpenCL framework. It consists of fundamental building blocks necessary for graph processing. This paper introduces the library and presents several case studies on how to leverage it for a variety of representative graph problems. We evaluate application performance on an AMD GPU and investigate optimization approaches to improve performance.

Modern heterogeneous multiprocessors integrate CPU and GPU together to provide a boost to computational performance. Data sharing and communication between CPU and GPU has been a critical issue for the final speedup. With tighter integration of CPU and GPU, it has the advantage of sharing and moving data more efficiently in order to leverage the computational power that a GPU can provide. Initially, DMA or PCIe devices were used to transfer data between CPU and GPU with low efficiency and little flexibility. Recently a single address space and coherent cache hierarchies are being adopted in heterogeneous architectures to share data more efficiently. Thus it poses new challenge to understand the communication overheads in this new context and to improve communication efficiencies for these architectures. This paper proposes a novel approach called iCHAT (inter-Cache Hardware-Assistant data Transfer) to manage data transfer between the CPU cache and the GPU cache efficiently. The iCHAT technique proposed in this paper detects the communication patterns and eagerly evicts data from the owner's caches and prepares for the requestor's demand. We implement the iCHAT design in a simulator based on gem5 and an AMD in-house GPU simulator. Experimental results show that the communication related eviction traffic is reduced by an average of 40% and the total directory traffic is reduced by 8% on average. We implement a bounding experiment that provides a quantitative evaluation of inter CPU-GPU transfers and requests to communication data, which indicates that iCHAT could achieve on average 1.4x speedup for Rodinia benchmark suite and 1.2x speedup for AMD SDK APPs.

Tumour associated epilepsy (TAE) is common, debilitating and often not successfully controlled by surgical resection of the tumour and administration of multiple anti-epileptic drugs. It represents a cause of significant lost quality of life in an incurable disease and is therefore an important subject for ongoing research. The pathogenesis of TAE is likely to be multifactorial and involve, on the microscopic level, the interaction of genetic factors, changes in the peritumoural microenvironment, alterations in synaptic neurotransmitter release and re-uptake, and the excitotoxic effects of glutamate. On a macroscopic level, the occurrence of TAE is likely to be influenced by tumour size, location and interaction with environmental factors. The optimal treatment of TAE requires a multi-disciplinary approach with input from neurosurgeons, neurologists, radiologists, pathologists and basic scientists. This article reviews the current literature regarding the incidence, treatment, and aetiology of TAE.

Adenosine-enhanced ischemic preconditioning extends the protection of ischemic preconditioning by both significantly decreasing infarct size and significantly enhancing postischemic functional recovery.The effects of adenosine-enhanced ischemic preconditioning on necrosis and apoptosis were investigated in the sheep heart using models of stunning (15 minutes regional ischemia, 120 minutes reperfusion) and ischemia-reperfusion (30 and 60 minutes regional ischemia, 120 minutes reperfusion). Ischemic preconditioned hearts received 5 minutes regional ischemia, 5 minutes reperfusion before ischemia. Adenosine-enhanced ischemic preconditioned hearts received a 10 mmol/L adenosine bolus (10 mL) through the left atrium coincident with ischemic preconditioning. Adenosine hearts received a 10 mmol/L bolus (10 mL) of adenosine. Regional ischemic hearts received no pretreatment.Minimal apoptosis (45 per 3,000 myocytes) was observed in the stunning models but was significantly increased with ischemia-reperfusion in regional ischemic hearts after 30 minutes (p0.05 versus ischemic preconditioning, adenosine, or adenosine-enhanced ischemic preconditioning) and in adenosine and ischemic preconditioned hearts after 60 minutes ischemia (p0.05 versus adenosine-enhanced ischemic preconditioning). DNA laddering was apparent after 60 minutes ischemia in regional ischemia, adenosine, and ischemic preconditioning but not in adenosine-enhanced ischemic preconditioned hearts.Adenosine-enhanced ischemic preconditioning significantly ameliorates necrosis and apoptosis in the regional ischemic blood-perfused heart.

One aim of this study was to determine the incidence of new radiographic pulmonary abnormalities during hospitalization after cardiac surgery. Another aim was to determine if such abnormalities are more common among patients who had left internal mammary artery (LIMA) grafting. The predictive value of radiographic abnormalities for clinically important pulmonary morbidity was also determined. The anteroposterior chest radiographs of 152 patients obtained by portable equipment were evaluated to determine the incidence of new postoperative radiographic pulmonary abnormalities such as atelectasis, consolidation, infiltrate, and pleural effusion. Clinically important pulmonary morbidity was defined as a delay in tracheal extubation or discharge from the hospital because of a pulmonary reason. Among the 89 patients who had LIMA grafting and left pleurotomy, there was an 88% incidence of left-sided pulmonary abnormalities; a 73% incidence of left-sided atelectasis; and a 55% incidence of left-sided effusion. Among the 63 patients who had saphenous vein grafting only and/or valvular surgery, the respective incidences were 68%, 54%, and 35%, which were lower (P less than or equal to 0.05) than those in the patients who had LIMA grafting. There was no significant difference in abnormalities between the saphenous vein grafting and the valvular surgery groups. The 35% incidence of left-sided pleural effusion when LIMA grafting and pleurotomy were not performed was unexpectedly high. There was no association between radiographic abnormalities and age, the duration of cardiopulmonary bypass, and the duration of aortic occlusion, indicating that cardiopulmonary bypass was not a primary etiology of these radiographic abnormalities.(ABSTRACT TRUNCATED AT 250 WORDS)

In brief Although popular reporting would indicate otherwise, overall injury rates in youth hockey have decreased during the past decade. Most injuries that do occur are not serious, but those that are demand prompt and skillful attention: The alarming increase in head, neck, and spine injuries, in addition to the death of a young player struck in the anterior chest by a high-velocity puck, emphasizes the need for a structured on-ice approach to stabilizing and managing injuries ranging from musculoskeletal to life-threatening. More injuries could be avoided by analyzing more injury data, improving both protective equipment and rink design, teaching injury prevention, and strictly enforcing the rules.

The large working sets of commercial and scientific workloads stress the L2 caches of Chip Multiprocessors (CMPs). Some CMPs use a shared L2 cache to maximize the on-chip cache capacity and minimize off-chip misses. Others use private L2 caches, replicating data to limit the delay due to global wires and minimize cache access time. Recent hybrid proposals use selective replication to balance latency and capacity, but their static replication rules result in performance degradation for some combinations of workloads and system configurations. This paper proposes Adaptive Selective Replication (ASR), a mechanism that dynamically monitors workload behavior to control replication. ASR replicates cache blocks only when it estimates the benefit of replication (lower L2 hit latency) exceeds the cost (more L2 misses). Full-system simulations of 8-processor CMPs show that ASR provides robust performance: improving performance by as much as 29% versus shared caches, 19% versus private caches, and 12% versus CMP-NuRapid [9] and Victim Replication [41]. Furthermore, while ASR does not improve the performance of all workloads, it provides performance stability by always performing at least comparably to the best alternative including Cooperative Caching [8].

One key advantage of solar power over more traditional power sources is its modular nature, allowing it to be used in remote locations or as a supplementary source of power. Recent studies show fuel cell technology as a good means of providing a continuous supply of electricity from a solar array, eliminating drawbacks caused by solar energy's cyclical nature. The high power density of such a system makes it ideal for use in areas such as unmanned aerial vehicles and space exploration. Due to the complexity and relatively high initial cost of current fuel cells, however, optimization of such a system is critical. This paper examines a dynamic model of a solar regenerative fuel cell system built in MATLAB Simulink. The system uses a polymer electrolyte membrane (PEM) fuel cell, running on stored hydrogen and oxygen, to produce power when solar energy is insufficient. It uses a PEM based electrolyzer to produce hydrogen and oxygen from water when solar energy exceeds demand. The mathematical model includes modules for each component, including solar cells, fuel cell, electrolyzer, and auxiliary systems. Models were built based on fundamental physics to the extent practical. The individual modules were first tested for their performances and then were integrated to form an integrated solar powered regenerative fuel cell system. The simulations were carried out for a day and night cycle and the results show that the closed loop system can be operated providing continuous supply of electric power.

In response to increasing (relative) wire delay, architects have proposed various technologies to manage the impact of slow wires on large uniprocessor L2 caches. Block migration (e.g., D-NUCA and NuRapid) reduces average hit latency by migrating frequently used blocks towards the lower-latency banks. Transmission Line Caches (TLC) use on-chip transmission lines to provide low latency to all banks. Traditional stride-based hardware prefetching strives to tolerate, rather than reduce, latency. Chip multiprocessors (CMPs) present additional challenges. First, CMPs often share the on-chip L2 cache, requiring multiple ports to provide sufficient bandwidth. Second, multiple threads mean multiple working sets, which compete for limited on-chip storage. Third, sharing code and data interferes with block migration, since one processor's low-latency bank is another processor's high-latency bank. In this paper, we develop L2 cache designs for CMPs that incorporate these three latency management techniques. We use detailed full-system simulation to analyze the performance trade-offs for both commercial and scientific workloads. First, we demonstrate that block migration is less effective for CMPs because 40-60% of L2 cache hits in commercial workloads are satisfied in the central banks, which are equally far from all processors. Second, we observe that although transmission lines provide low latency, contention for their restricted bandwidth limits their performance. Third, we show stride-based prefetching between L1 and L2 caches alone improves performance by at least as much as the other two techniques. Finally, we present a hybrid design-combining all three techniques-that improves performance by an additional 2% to 19% over prefetching alone.

Recent advances in global positioning system (GPS) technology have made it possible to detect millimeter scale changes in the Earth’s surface. Using these systems it has been possible to detect relative motion between the large plates of the outer most rigid layer of Earth. These motions previously had only been inferred from indirect evidence of the plates’ motions. A remarkable result from these studies is that the plate motions are nearly continuous and not an episodic process, even on human time scales. Analyses of these motions indicate that much of the motion between plates occurs without producing earthquakes (1). In addition to monitoring interplate motions, GPS arrays are making it possible to study present deformation occurring within mountain belts. The strain rate models obtained from the GPS arrays then can be used to test specific theories of crustal deformation in mountain belts.

Twenty-four patients required an intra-aortic balloon pump placed through the aortic arch during cardiac operations from 1985 to 1993. The operative procedures of the 24 patients requiring arch balloon pumps included aortocoronary bypass (14), redo aortocoronary bypass (3), valve replacement (3), aortocoronary bypass with concomitant ventricular septal defect repair (1), heart transplantation (2), and aortic to right ventricle fistula repair (1). Mortality was 54%. Morbidity included cerebral vascular accident (17%), acute renal failure (29%), left ventricular thrombus (4%), sternal wound infection (4%), and mediastinal exploration secondary to bleeding from the balloon pump site (4%). This review suggests that (1) mortality for patients requiring arch balloon is significant, (2) complications of cerebral vascular accident and renal failure may be increased, and (3) severe peripheral vascular disease is associated with arch balloon placement and subsequent increased morbidity and mortality.

The aim of this investigation was to compare the effectiveness of several different methods of root instrumentation by measuring and comparing the amount of residual stained material following treatment. Also, 2 different methods of quantitating residual stained material were compared. A total of 90 periodontally-involved teeth were extracted and randomly assigned to 1 of 8 treatment groups or to the untreated control group. Experimental treatments consisted of one or a combination of the following: Columbia 13-14 curet, P-10 ultrasonic instrument, diamond-coated P-10 ultrasonic instrument, or antiformin/citric acid chemical treatment. Selected samples were examined using light microscopy in order to determine the amount of cementum removed during root instrumentation. Residual stained material was quantitated using a method of grid-square analysis as well as by the use of photographs and a digitizing tablet. Following instrumentation, it was noted in histologic sections that the complete removal of cementum was rare, although all of the cementum was removed by some experimental treatments in some areas. All mechanical methods of root instrumentation were found to be essentially equal in effectiveness with respect to the removal of plaque and calculus. Chemical debridement alone was found to be ineffective. It was further noted that the grid-square method of analysis produced measurements that were 2 to 8 times higher than measurements produced by the digitizing tablet.

A patient was monitored prior to, during, and after cardiac arrest with a Holter monitor and an electrocardiograph. The arrest occurred without any premonitory signs on the ECG. At the onset of the arrest, torsades de pointes ventricular tachycardia occurred, which quickly degenerated into ventricular fibrillation. After a successful second defibrillation, the patient developed Osborn waves, which subsided within a few minutes.

retrosternally, using the costoclavicular ligament as a fulcrum. Posterior dislocation may compromise structures of the thoracic outlet and anterior mediastinal space, including the trachea, esophagus, nerves (brachial plexus, recurrent laryngeal), and the great vessels (superior vena cava, aorta). Posterior dislocations are commonly reduced in the operating room if a cardiothoracic surgeon is readily available. Because the medial epiphysis is the last to ossify and close (approximately at 19 years and between 23 and 25 years, respectively), clavicle shaft displacements seen with physeal disruptions at the medial end of the clavicle in adolescents and young adults may mimic sternoclavicular dislocations [2]. Conventional radiographic diagnosis of sternoclavicular dislocations may be difficult because radiographic‐anatomic superimposition precludes an “ideal” lateral image. Nonetheless, many unique views have been proposed, including the Rockwood (serendipity), Hobb, Kattan [4], and Heinig views. On nonrotated frontal radiographs, a difference in relative craniocaudal positions of the medial clavicles greater than 50% of the width of the heads of the clavicles suggests dislocation. When the diagnosis remains unclear (Figs. 2 and 3), adjunctive imaging is indicated for surgical planning of combined medial clavicle fracture‐dislocations and to examine potential neurovascular and tracheal injuries in posterior dislocations. Thin-section ( ≤ 3‐mm collimation) axial CT is the standard for the diagnosis of sternoclavicular joint dislocations.

Excerpt To the Editors:Deep vein thrombophlebitis ("crural phlebitis") associated with acupuncture has been previously reported (1). I report another such occurrence. A 64-year-old healthy, active ...

In many patients with peripheral vascular disease, conventional arteriograms are not adequate to make proper preoperative decisions. In the past, these inadequate studies led to surgical exploration of vessels and intraoperative angiography to determine operability. Such efforts prolonged operating time and potentially had adverse effects on amputation levels. Recently, intra-arterial digital subtraction angiography (IDSA) has provided an excellent means to further evaluate these patients preoperatively. We presently have 30 patients in whom IDSA supplemented routine aortography and runoff studies. When standard angiographic studies were considered inadequate, the catheter was positioned appropriately and IDSA was obtained. Inadequate lower extremity distal runoff in 23 patients and no proximal or distal runoff in seven patients prompted the IDSA. The IDSA study yielded further information on all patients, and 26 of 30 patients underwent successful bypass operation. In all 17 patients having femoropopliteal or femorotibial bypass, the IDSA was confirmed by an intraoperative (after bypass) angiogram. Nine patients had inflow procedures, and operative findings corroborated the IDSA. Two patients refused surgery and two patients were not candidates for revascularization. The IDSA study provided an accurate "road map," eliminated unnecessary vessel exploration, saved vital operative time, and prevented compromise of potential amputation levels.

A left ventricular aneurysm developed in 3 patients sustaining blunt chest injury. Evidence of an acute myocardial infarction on the electrocardiogram and enzyme analysis prompted cardiac catheterization, which revealed total occlusion of the left anterior descending coronary artery in 2 of the 3 patients. Ventricular aneurysmectomy was performed in each patient. A review of the literature revealed 32 previously reported patients with left ventricular aneurysm caused by blunt trauma. Clinical features, catheterization or autopsy findings, and outcome are examined.

For decades, the preparation of a hyperthyroid patient for surgery took several weeks or months utilizing thyroid blocking agents and iodine. In 1973, a preliminary report of 20 patients with hyperthyroidism treated with propranolol and thyroidectomy was presented. It was found that a thyrotoxic patient could be prepared for surgery, in an emergency, by intravenous propranolol in less than an hour, or electively by oral propranolol within 24 hours. Since then, 140 additional patients have been similarly treated. It continues to be true at this institution that propranolol, a beta-adrenergic blocking agent, effectively neutralizes the symptoms of autonomic hyperactivity, including sweating, tremor, fever, dilation of blood vessels, and increased pulse rate without significantly affecting thyroid function. An average dose of 160 mg/day was used, with a range of 40 to 320 mg/day. In none of these patients was iodine used; in fact, its use with propranolol is considered unnecessary. A subtotal, near total, or total thyroidectomy was done in all patients, resulting in a 55% incidence of hypothyroidism. There was no postoperative thyroid storm, nerve injury, or permanent hypoparathyroidism. It is believed that the administration of propranolol alone provides a rapid, safe, and effective preparation of the thyrotoxic patient for thyroidal or extrathyroidal surgical procedures during the perioperative period.

Concomitant coronary revascularization and implantation of the automatic cardioverter/defibrillator is an increasingly common procedure. To determine whether cardioversion/defibrillation thresholds measured after weaning patients from cardiopulmonary bypass are sufficient to justify immediate implantation of the pulse generator, we prospectively compared postpump values to those obtained 1 week later in five patients. R-wave amplitudes during both sinus rhythm and ventricular tachycardia, lead impedance, defibrillation thresholds and cardioversion thresholds remained stable or improved from the postpump to the 1 week values. Five other patients had the generator implanted at the time of revascularization. Immediate postbypass cardioversion thresholds (mean 10 +/- 8 joules) in these ten patients did not significantly differ from those of 20 nonpump implantations (VT mean 7 +/- joules; VF 15 +/- 4 joules and defibrillation thresholds mean 17 +/- 6 joules). These findings suggest that the residual effects of cardioplegia, core-cooling and operative ischemia have no significant effects on intraoperative testing of implanted defibrillators. This clinical experience supports the practice of immediate implantation of the pulse generator at the time of revascularization.

Battery Energy Storage Test (BEST) Facility experiences with utility-sited and operated battery energy storage produce information about shipment, installation, safety, operation, maintenance, efficiency, capacity, responsiveness and power quality of the systems tested. This paper presents information in each of these categories derived from baseline testing of 500 kWh developmental zinc chloride and peak-shaving demonstration lead-acid batteries, and from one-year of cycling the BEST Facility's 1.8 MWh lead-acid, facility shakedown battery. Conclusions from testing are guiding the further development of these technologies.

Iatrogenic aortic injury occurring during either coronary bypass grafting or valve replacement is a well-recognized complication of cardiac surgery. We retrospectively reviewed our experience and found 11 cases occurring in a case load of 8,945 hearts (incidence of 0.12%). All 11 cases were repaired, with 10 patients surviving. The type of repair used usually was determined by when the diagnosis was made. When an intraoperative diagnosis was made, a local repair was done in four of six cases. If a postoperative diagnosis was made, then all five patients needed the ascending aorta replaced. With early diagnosis and rapid repair, good surgical results can be achieved.

A method of APT programming and postprocessor design has been developed which permits more efficient data preparation for numerical control (NC) machine tools and then allows this data to be quickly and easily exchanged among different NC machines. This is accomplished through rigorous specification of the APT post-processor language based upon new ANSI standards for APT plus a comprehensive definition of the machining functions which should result from the use of each APT language statement. Individual postprocessors are modified to process each statement in the same manner. This document sets forth minimum specifications for the procurement of APT Postprocessors consistent with the standardized postprocessing language concept. It is expected that these specifications will be used in future machine tool procurements. The concept was successfully demonstrated in production by processing a single APT data package on three different milling-drilling type machine tools. A 23% increase in NC manufacturing efficiency is projected. (Author)

Twenty-two open-heart operations have been performed on 21 patients receiving chronic renal dialysis. These cases include 16 aortocoronary bypasses and six valve replacements. The average time on dialysis prior to surgery was 26 months; 18 of 21 patients were in NYHA grade 3 or 4. Twenty-seven postoperative complications occurred, with six requiring further surgery and 21 treated nonsurgically. Two perioperative deaths occurred, both due to sepsis. Long-term follow-up was achieved on all hospital survivors. Ten patients remain alive with a mean follow-up of 21 months. At a mean of 16.5 months after surgery, nine deaths occurred, with only two due to known cardiac problems. In summary, indicated cardiac surgery can be performed on chronic renal dialysis patients with a reasonable morbidity and mortality; however, the long-term survival of our patients has not been assured by a successful cardiac operation.