bluuebunny/crossref_metadata_2025 huggingface dataset:
HMF
Authors: Leijen Daan
Published: September 2008

HMF is a conservative extension of Hindley-Milner type inference with first-class polymorphism. In contrast to other proposals, HML uses regular System F types and has a simple type inference algorithm that is just a small extension of the usual Damas-Milner algorithm W. Given the relative simplicity and expressive power, we feel that HMF can be an attractive type system in practice. There is a reference implementation of the type system available online together with a technical report containing proofs (Leijen 2007a,b).
FPH
Authors: Vytiniotis Dimitrios , Weirich Stephanie , Peyton Jones Simon
Published: September 2008

Languages supporting polymorphism typically have ad-hoc restrictions on where polymorphic types may occur. Supporting "firstclass" polymorphism, by lifting those restrictions, is obviously desirable, but it is hard to achieve this without sacrificing type inference. We present a new type system for higher-rank and impredicative polymorphism that improves on earlier proposals: it is an extension of Damas-Milner; it relies only on System F types; it has a simple, declarative specification; it is robust to program transformations; and it enjoys a complete and decidable type inference algorithm.
Mixin' up the ML module system
Authors: Dreyer Derek , Rossberg Andreas
Published: September 2008

ML modules provide hierarchical namespace management, as well as fine-grained control over the propagation of type information, but they do not allow modules to be broken up into mutually recursive, separately compilable components. Mixin modules facilitate recursive linking of separately compiled components, but they are not hierarchically composable and typically do not support type abstraction. We synthesize the complementary advantages of these two mechanisms in a novel module system design we call MixML.

A MixML module is like an ML structure in which some of the components are specified but not defined. In other words, it unifies the ML structure and signature languages into one. MixML seamlessly integrates hierarchical composition, translucent MLstyle data abstraction, and mixin-style recursive linking. Moreover, the design of MixML is clean and minimalist; it emphasizes how all the salient, semantically interesting features of the ML module system (as well as several proposed extensions to it) can be understood simply as stylized uses of a small set of orthogonal underlying constructs, with mixin composition playing a central role.
Compiling self-adjusting programs with continuations
Authors: Ley-Wild Ruy , Fluet Matthew , Acar Umut A.
Published: September 2008

Self-adjusting programs respond automatically and efficiently to input changes by tracking the dynamic data dependences of the computation and incrementally updating the output as needed. In order to identify data dependences, previously proposed approaches require the user to make use of a set of monadic primitives. Rewriting an ordinary program into a self-adjusting program with these primitives, however, can be difficult and error-prone due to various monadic and proper-usage restrictions, some of which cannot be enforced statically. Previous work therefore suggests that self-adjusting computation would benefit from direct language and compiler support.

In this paper, we propose a language-based technique for writing and compiling self-adjusting programs from ordinary programs. To compile self-adjusting programs, we use a continuation-passing style (cps) transformation to automatically infer a conservative approximation of the dynamic data dependences. To prevent the inferred, approximate dependences from degrading the performance of change propagation, we generate memoized versions of cps functions that can reuse previous work even when they are invoked with different continuations. The approach offers a natural programming style that requires minimal changes to existing code, while statically enforcing the invariants required by self-adjusting computation.

We validate the feasibility of our proposal by extending Standard ML and by integrating the transformation into MLton, a whole-program optimizing compiler for Standard ML. Our experiments indicate that the proposed compilation technique can produce self-adjusting programs whose performance is consistent with the asymptotic bounds and experimental results obtained via manual rewriting (up to a constant factor).
NixOS
Authors: Dolstra Eelco , Löh Andres
Published: September 2008

Existing package and system configuration management tools suffer from an
imperative model
, where system administration actions such as upgrading packages or changes to system configuration files are stateful: they destructively update the state of the system. This leads to many problems, such as the inability to roll back changes easily, to run multiple versions of a package side-by-side, to reproduce a configuration deterministically on another machine, or to reliably upgrade a system. In this paper we show that we can overcome these problems by moving to a
purely functional system configuration model
. This means that all static parts of a system (such as software packages, configuration files and system startup scripts) are built by pure functions and are immutable, stored in a way analogously to a heap in a purely function language. We have implemented this model in
NixOS
, a non-trivial Linux distribution that uses the
Nix package manager
to build the entire system configuration from a purely functional specification.
Experience report
Authors: Duke David J. , Borgo Rita , Runciman Colin , Wallace Malcolm
Published: September 2008

Scientific visualization is the transformation of data into images. The
pipeline model
is a widely-used implementation strategy. This term refers not only to linear chains of processing stages, but more generally to demand-driven networks of components. Apparent parallels with functional programming are more than superficial: e.g. some pipelines support streams of data, and a limited form of lazy evaluation. Yet almost all visualization systems are implemented in imperative languages. We challenge this position. Using Haskell, we have reconstructed several fundamental visualization techniques, with encouraging results both in terms of novel insight and performance. In this paper we set the context for our modest rebellion, report some of our results, and reflect on the lessons that we have learned.
Report on the tenth ICFP programming contest
Authors: Dolstra Eelco , Hage Jurriaan , Heeren Bastiaan , Holdermans Stefan , Jeuring Johan , Löh Andres , Löh Clara , Middelkoop Arie , Rodriguez Alexey , van Schie John
Published: September 2008

The ICFP programming contest is a 72-hour contest, which attracts thousands of contestants from all over the world. In this report we describe what it takes to organise this contest, the main ideas behind the contest we organised, the task, how to solve it, how we created it, and how well the contestants did.

This year's task was to reverse engineer the DNA of a stranded alien life form to enable it to survive on our planet. The alien's DNA had to be modified by means of a
prefix
that modified its meaning so that the alien's phenotype would approximate a given "ideal" outcome, increasing its probability of survival. About 357 teams from 39 countries solved at least part of the contest. The language of choice for discriminating hackers turned out to be C++.
Review of combinatorial optimization
Authors: Cornuéjols Gérard
Published: September 2008

This book is based on a series of ten lectures given by Cornuéjols at a CBMS-NSF regional conference in 1999. It is a monograph on the polyhedral combinatorics of packing and covering problems. The fundamental approach is to formulate a combinatorial optimization problem as an integer linear programming problem and then determine conditions under which the feasible region of the linear programming (LP) relaxation of the problem has integral vertices. In such cases, the problem can be solved efficiently by simply solving the LP relaxation.
Can quantum mechanics help distributed computing?
Authors: Broadbent Anne , Tapp Alain
Published: September 2008

We present a brief survey of results where quantum information processing is useful to solve distributed computation tasks. We describe problems that are impossible to solve using classical resources but that become feasible with the help of quantum mechanics. We also give examples where the use of quantum information significantly reduces the need for communication. The main focus of the survey is on communication complexity but we also address other distributed tasks.
Gem #10: limited types in Ada 2005
Authors: Duff Bob
Published: September 2008

Ada Gem #10 -- An extended_return_statement may be used to give a name to the result object being created by a function.
Gem #11: limited types in Ada 2005
Authors: Duff Bob
Published: September 2008

Ada Gem #11 We show here how limited constructor functions can be used in various contexts to build new limited objects in place.
Gem #12: limited types in Ada 2005
Authors: Duff Bob
Published: September 2008

Ada Gem #12 -- We show how the <> notation in aggregates may be used to make better use of record-component default values, thus avoiding duplication of code.
Gem #13: interrupt handling idioms (part 1)
Authors: Rogers Pat
Published: September 2008

Ada Gem #13 -- There are two design idioms commonly used when handling interrupts with Ada. One has more of the characteristics associated with good software engineering, the other somewhat better performance. We explore these two idioms in this gem.
Gem #14: interrupt handling idioms (part 2)
Authors: Rogers Pat
Published: September 2008

Ada Gem #14 -- There are two design idioms commonly used when handling interrupts with Ada. One has more of the characteristics associated with good software engineering, the other somewhat better performance. We explore these two idioms in this gem.
Gem #15: timers
Authors: Vo Anh
Published: September 2008

Ada Gem #15 -- Timers are essential software elements of embedded and real-time systems. Thus, making an intuitive and easy way to create timers helps in the software design process.
Gem #17: pragma no_return, part 2 (functions)
Authors: Duff Bob
Published: September 2008

Ada Gem #17 -- GNAT warns about functions that might reach their "end", and sometimes these warnings are false alarms. Pragma No_Return can be used to suppress such false alarms.
Gem #18: warnings in GNAT
Authors: Duff Bob
Published: September 2008

Ada Gem #18 -- This "gem" is not about the Ada language, but about a set of GNAT-specific features related to warnings. We discuss how to make the best use of GNAT's warnings.
Gem #21: how to parse an XML text
Authors: Briot Emmanuel
Published: September 2008

Ada Gem #21 -- The World Wide Web Consortium (W3C) develops various specifications around the XML file format. In particular, it specifies various APIs to load, process and write an XML file. Although these APIs are not specified for Ada, XML/Ada tries to conform as closely as possible to them. This gem describes how to use XML/Ada to parse an XML file.
Blogosphere
Authors: Agarwal Nitin , Liu Huan
Published: September 2008

Weblogs, or Blogs, have facilitated people to express their thoughts, voice their opinions, and share their experiences and ideas. Individuals experience a sense of community, a feeling of belonging, a bonding that members matter to one another and their niche needs will be met through online interactions. Its open standards and low barrier to publication have transformed information consumers to producers. This has created a plethora of open-source intelligence, or "collective wisdom" that acts as the storehouse of over-whelming amounts of knowledge about the members, their environment and the symbiosis between them. Nonetheless, vast amounts of this knowledge still remain to be discovered and exploited in its suitable way. In this paper, we introduce various state-of-the-art research issues, review some key elements of research such as tools and methodologies in Blogosphere, and present a case study of identifying the influential bloggers in a community to exemplify the integration of some major aspects discussed in this paper. Towards the end, we also compare and contrast the blogosphere and social networks and the research therein.
Data mining with cellular automata
Authors: Fawcett Tom
Published: September 2008

A cellular automaton is a discrete, dynamical system composed of very simple, uniformly interconnected cells. Cellular automata may be seen as an extreme form of simple, localized, distributed machines. Many researchers are familiar with cellular automata through Conway's Game of Life. Researchers have long been interested in the theoretical aspects of cellular automata. This article explores the use of cellular automata for data mining, specifically for classification tasks. We demonstrate that reasonable generalization behavior can be achieved as an emergent property of these simple automata.
A privacy-aware trajectory tracking query engine
Authors: Gkoulalas-Divanis Aris , Verykios Vassilios S.
Published: September 2008

Advances in telecommunications and GPS sensors technology have made possible the collection of data like time series of locations, related to the movement of individuals. The analysis of this, so-called trajectory data, is beneficial both for the individuals (e.g., through location-based services) and for the community as a whole (e.g., decision support for urban planning or traffic control). However, because of the very nature of this data, strict safeguards must be enforced to ensure the privacy of the individuals, whose movement is recorded.

In this paper, we present a privacy-aware trajectory tracking query engine that offers strict guarantees about what can be observed by untrusted third parties. Through the query engine, subscribed users can gain restricted access to an in-house trajectory data warehouse, to perform certain analysis tasks. In addition to regular queries involving non-spatial non-temporal attributes, the engine supports a variety of spatiotemporal queries, including range queries, nearest neighbor queries and queries for aggregate statistics. The query results are augmented with fake trajectory data (dummies) to fulfil the requirements of
K
-anonymity. Through qualitative analysis, we prove the effectiveness of our approach towards blocking certain types of attacks, while minimally distorting the dataset.
8
th
French-speaking conference on knowledge discovery and management (EGC2008)
Authors: Guillet Fabrice , Trousse Brigitte
Published: September 2008

In this paper, we provide a report about the 8th French-speaking conference on Knowledge Discovery and Management (EGC'2008) [1] held in Sophia Antipolis, France, from January 29
th
to February 1
st
, 2008. Since 2001, this annual conference has been supported by the French-speaking association (EGC Association) which aims at promoting Data Mining and Knowledge Management for both research issues and applications in companies. EGC2008 may be summarized in some key figures: 130 submitted papers, 40 accepted long papers (33% selection ratio) published in a special issue of a review and completed with 30 short papers, 15 posters, and 8 software demonstrations; 9 joined workshops and 2 tutorials; 4 keynote talks; a best paper contest rewarded by 2 prizes of 1500 euros each; and 250 participants from 14 countries.

The 9th EGC conference will be held in Strasbourg, France, in January 27-30, 2009 [2].
Role of Glucosinolates in Insect-Plant Relationships and Multitrophic Interactions
Authors: Hopkins Richard J. , van Dam Nicole M. , van Loon Joop J.A.
Published: September 2008

Glucosinolates present classical examples of plant compounds affecting insect-plant interactions. They are found mainly in the family Brassicaceae, which includes several important crops. More than 120 different glucosinolates are known. The enzyme myrosinase, which is stored in specialized plant cells, converts glucosinolates to the toxic isothiocyanates. Insect herbivores may reduce the toxicity of glucosinolates and their products by excretion, detoxification, or behavioral adaptations. Glucosinolates also affect higher trophic levels, via reduced host or prey quality or because specialist herbivores may sequester glucosinolates for their own defense. There is substantial quantitative and qualitative variation between plant genotypes, tissues, and ontogenetic stages, which poses specific challenges to insect herbivores. Even though glucosinolates are constitutive defenses, their levels are influenced by abiotic and biotic factors including insect damage. Plant breeders may use knowledge on glucosinolates to increase insect resistance in Brassica crops. State-of-the-art techniques, such as mutant analysis and metabolomics, are necessary to identify the exact role of glucosinolates.
New Insights on Intravenous Fluids, Diuretics and Acute Kidney Injury
Authors: Townsend Derek R. , Bagshaw Sean M.
Published: September 2008

Acute kidney injury (AKI) is commonly and increasingly encountered in patients with critical illness. Fluid therapy is the cornerstone for the prevention and management of critically ill patients with AKI. New data have emerged that have raised concern that specific types of fluid (i.e. hydroxyethylstarch) may either contribute to or exacerbate AKI. Additional data have accumulated to indicate that the unnecessary accumulation of fluid and volume overload can negatively impact clinical outcomes. This finding may be further compounded in patients with oliguric AKI where solute and free water elimination are impaired. Diuretic therapy in AKI remains controversial. However, diuretic use is common, despite a paucity of evidence to show improved clinical outcomes. There are few therapeutic interventions proven to impact the clinical course and outcome of critically ill patients with established AKI. Current management strategies center largely on supportive care, with rapid resuscitation, removal of the stimulus contributing to AKI, judicious avoidance of complications, and allowing time for recovery. In this review, we explore recent insights on intravenous fluid therapy, volume overload, and diuretic therapy in the context of the critically ill patients with AKI.
Chemical Composition of Baboon Plant Foods: Implications for the Interpretation of Intra- and Interspecific Differences in Diet
Authors: Barton R.A , Whiten A. , Byrne R.W. , English M.
Published: September 2008

Information on the chemical composition of baboon foods from the Laikipia Plateau, Kenya, is presented. Despite some differences in methods, results of analyses performed on the same foods at different sites were found to be extremely consistent, encouraging the view that meaningful intra- and interspecific comparisons of diet selection are feasible. Contrary to assumptions in the literature, no relationship between the abundance of food types and their chemical composition was found, nor was the foliage eaten by the baboons found to be a low-quality or high-fibre item in comparison with fruits and storage organs. Emphasis is placed on the need for caution in the use of simplistic dietary taxonomies which imply phyto-chemical and ecological homogeneity within broad food categories. Comparisons between three species revealed marked differences in the chemical composition of their diets; in particular, baboon diets were found to be higher in protein and lower in fibre than those of either lowland gorillas or Malaysian leaf monkeys, and differences in condensed tannin levels were also found. The relationship between these differences and the socio-ecology of the three species is discussed.
Development of Behaviour in a Young Aye-Aye (Daubentonia madagascariensis) in Captivity
Authors: Winn Renée M.
Published: September 2008

This paper provides descriptive and quantitative information on the development of a young aye-aye in captivity during its first 10 months of life. The mother’s behaviour was observed to provide an adult standard against which to evaluate the young male’s development. Early development of the young aye-aye (including early vocalizations, locomotion and manipulation, acquisition of independence from the mother, threat/ defence and alarm) is described in qualitative terms. Quantitative data on a number of other behaviours were collected using focal-animal sampling. Overall, this study indicated that the young aye-aye is relatively poorly developed during the 2-month nest phase but shows rapid development in comparison to other primates once it has left the nest.
Distribution of Ruffed Lemurs (Varecia variegata) in Ranomafana National Park, Madagascar
Authors: White Frances J. , Overdorff Deborah J. , Balko Elizabeth A. , Wright Patricia C.
Published: September 2008

The distribution of Varecia variegata at 3 sites in Ranomafana National Park is consistent with the hypothesis that this specialized frugivore is the most susceptible of 12 sympatric lemur species to habitat disruption brought about by selective logging. Varecia is most abundant at the least disturbed site and absent from the most intensively logged site. The logged area showed lower values for overall tree basal area, crown diameters and tree height and an increase in the number of trees, presumably because of growing saplings. Varecia select large food trees of species that are preferentially logged. Although tree species diversity may be higher after logging, many Varecia food trees were absent from disturbed forests.
Muscle Fibre Composition and Innervation Ratios of the Extensor Digitorum and Extensor Hallucis Brevis Muscles in the Crab-Eating Macaque (Macaca fascicularis)
Authors: Mcitsumura Akiyoshi , Inokuchi Seiicliiro
Published: September 2008

The morphological and functional characteristics of the extensor digitorum and hallucis brevis muscles, the sole intrinsic muscles of the dorsum of the foot in the macaque, were investigated through dissection, the examination of muscle fibre composition, and counts of axon numbers. The total number of muscle fibers contained within the extensor digitorum (EHB) and extensor hallucis brevis (EDB) was almost 21,100. The population ratios of the three muscle fibre types of white, intermediate and red were 39, 23 and 38%, respectively, for EDB and 40, 23 and 37%, respectively, for EHB. The mean cross-sectional area of each fibre type (white, intermediate, red) tended to be larger in the EHB (2,098, 1,480 and 911 μm2) than in the EDB (1,695, 1,310 and 822 μm2) and the value were significantly different for white fibres of males. The percentage area of the three muscle fibre types and the ratio of the white, intermediate and red areas, were similar between the EHB (55, 23 and 22%, respectively) and the EDB (52, 23 and 25%, respectively). The white area was dominant with the value showing a somewhat larger figure in the EHB compared to that of the EDB. The number of motor units was estimated to be 197–234 on average and the innervation ratio was calculated as between 91 and 109. These results suggest that the muscle fibre composition and innervation ratio of the EHB and EDB, especially the EHB, might relate to the arboreal locomotion of the crab-eating macaque.
Ontogeny of the Knee Joint in Humans, Great Apes and Fossil Hominids: Pelvi-Femoral Relationships during Postnatal Growth in Humans
Authors: Tardieu Christine , Preitschoft Holger
Published: September 2008

Results of a study of the femoral bicondylar angle in adult and juvenile humans and great apes are presented. These results raise the question of whether or not the measurement reference of this angle is valid. This is because humans and great apes have a very different growth process of the distal epiphyseal suture of the femur during the period between birth and adulthood. The approximately 3 million years old juvenile femoral diaphyses attributed to Australopithecus afarensis (AL 333-110 and AL 333-111) were also studied. These specimens show an insertion of the diaphysis into the epiphysis of the simplified type typical of modern humans. This region is more convoluted in nonhuman anthropoids. Pelvifemoral interrelations are investigated through both longitudinal and cross-sectional radiographic studies of 23 human children. Growth changes in bicondylar and collo-diaphyseal angles, total femoral and femoral neck lengths, and interacetabular distance are correlated with age and to each other. These results are used to demonstrate the distinctive features of the Australopithecus afarensis fossil, AL 288–1.
Ontogenetic Variation in Small-Bodied New World Primates: Implications for Patterns of Reproduction and Infant Care
Authors: Garber Paul A. , Leigh R.
Published: September 2008

This paper explores relations of ontogeny, life history strategies and patterns of infant care in 11 species of small-bodied New World monkeys. Analysis of these data suggests that differences in the social systems of Aotus, Callicebus, Saimiri, Callimico, Saguinus, Leontopithecus, Cehuella and Callithrix are closely tied to both the costs of reproduction and to the ontogenetic requirements of maturing young. In Saimiri, both rapid prenatal body weight and perinatal brain growth result in relatively high metabolic costs to breeding females. These costs, coupled with minimal nonmaternal assistance in caregiving, appear to favor a reproductive strategy that limits offspring production to a single birth at 2-year intervals. In contrast, tamarins and marmosets are capable of producing twins twice in the same year. Prenatal investment in each offspring is relatively low, and the potentially high postnatal costs of nursing 2 infants are minimized by the evolution of a social system involving extensive extramaternal care-giving. Cooperative infant care in callitrichins (tamarins and marmosets) serves to distribute the metabolic costs of infant ontogeny among several group members. Callimico is also characterized by a high reproductive output, with females capable of producing a single infant twice during the year. Infants continue to grow rapidly after weaning. Patterns of infant development in Callimico are similar to those found in tamarins and marmosets and support a close phylogenetic relationship among these taxa. Aotus and Callicebus are characterized by an alternative strategy. In these taxa, a monogamous mating system is associated with paternal certainty, male parental care, and provisioning of the young. The transfer of male energetic resources to a single offspring allows night and titi monkeys to maintain a comparatively short interbirth interval (1 year). Ecological and social factors, such as predation and feeding competition, do not appear to adequately explain much of the observed variation in infant development and preadult growth rates in these platyrrhines. Instead, reproductive strategies are strongly linked to ontogenetic patterns and life histories.
Experimental Field Study of Spatial Memory and Learning in Wild Capuchin Monkeys (Cebus capucinus)
Authors: Garber P.A. , Paciulli L.M.
Published: September 2008

Despite a large body of data on diet and ranging patterns in prosimians, monkeys and apes, little is known regarding the types of information that non-human primates use when making foraging decisions. In a series of controlled field experiments, we tested the ability of wild capuchins (Cebus capucinus) at La Suerte Biological Research Station in north-eastern Costa Rica to remember the spatial positions of 13 feeding platforms and use olfactory and visual cues to identify baited (real bananas) versus sham (plastic bananas) feeding sites. The results indicate that when ‘place’ was predictable, the capuchins learned the spatial locations of food and non-food sites rapidly (one-trial learning). In a second experiment, the positions of baited feeding sites were random. In the absence of other information, the capuchins used the presence of a local landmark cue (yellow block) placed at reward platforms to select feeding sites. In a final experiment, there was evidence that expectations regarding the amount of food available at a platform (2 bananas vs. 1/2banana) had a significant influence on capuchin foraging decisions. Although the capuchins were sensitive to changes in experimental conditions, when they were given conflicting cues, spatial information was predominant over other information in selecting feeding sites.
Can Spider Monkeys (Ateles geoffroyi) Discriminate Vocalizations of Familiar Individuals and Strangers?
Authors: Teixidor Patricia , Byrne Richard W.
Published: September 2008

In a field experiment, tape-recorded vocalizations of spider monkeys (Ateles geoffroyi) were played back to investigate whether individuals were able to discriminate between group members and strangers. Monkeys responded remarkably similarly in the two cases, with no significant difference found between the numbers of calls given by an individual, or the types of call given. However, a group was more likely to give some vocal reaction when hearing a stranger’s call than when hearing one from an individual of their own community. Further, the only instances in which agonistic territorial behaviours occurred were in reaction to strangers’ playbacks. No significant effects on the response given were produced by the sex of the caller, the location and time of day of the broadcast, the size of the subgroup hearing the call or the activity in which they were involved. These results are discussed with respect to acoustic, social and ecological factors that may lead to the apparent lack of vocal discrimination of strangers within the community range.
Responses of Smooth Muscle to Quick Load Change Studied at High Time Resolution
Authors: Johansson Börje , Hellstrand Per , Uvelius Bengt
Published: September 2008

Quick-release and quick-stretch experiments have been performed on preparations of smooth muscle from rat portal vein and rabbit urinary bladder. The low equivalent mass of the isotonic lever (8 mg) implied that inertial oscillations were limited to the first 5–10 msec after the load step. The high time resolution achieved in this way enabled us to separate three components in the length response to a step change in force: (1) an immediate passive elastic recoil, (2) an isotonic velocity transient lasting 50–75 msec and (3) shortening of the contractile element after its full adjustment to the new load. The maximal series elastic recoil was about 10% of the total muscle length in portal vein but only some 3% in urinary bladder. Stiffness of series elasticity increased in proportion to force and was about 3 times higher in bladder than in portal vein at any force level. Force-velocity relations for loads less than Po could be fitted to Hill’s equation; Vmax in 4 AC-stimulated portal veins was 0.53 ± 0.03 muscle lengths/sec and in 8 K+-activated bladder preparations 0.18 ± 0.01 muscle lengths/sec. Application of loads greater than Po produced rates of lengthening greater than expected from an extrapolation of Hill’s hyperbola. The nature of the transient component is discussed in the light of recent studies of force and velocity transients in skeletal muscle.
The Reactivity of Iliac Vascular Strips from Spontaneously Hypertensive and Normotensive Rats
Authors: Swamy V.C. , Triggle D.J.
Published: September 2008

Comparison of responses to norepinephrine (NE) and KC1 of iliac arterial strips from spontaneously hypertensive rats (SHR) and three strains of normotensive rats (NR) were made in tissues obtained from 5- to 7- and 15- to 17-week-old animals. The systolic blood pressures of young rats were essentially similar while the 15- to 17-week-old SHR had markedly higher blood pressures than their normotensive counterparts. The contractility and sensitivity of strips to NE from SHR were less than those from NR in both age groups. Relaxation of NE-induced responses in normal physiological or calcium-free solutions was consistently more rapid with SHR tissues. In calcium-free solution, the fast component of responses to NE was smaller in young SHR; no difference in dependence on calcium was seen in tissues from older rats. Differences in KCl-induced responses were seen only in young animals, where reduced contractility and slower relaxation in normal physiological solutions were obtained with strips from SHR. We conclude that the iliac artery from SHR differs intrinsically from those of NR since the differences in responses were evident in young rats prior to the development of stable hypertensive state in the SHR.
Intra- and Extraneuronal Monoamine Oxidase
Authors: Fowler Christopher J. , Magnusson Olle , Ross Svante B.
Published: September 2008

By use of monoamine reuptake inhibitors, it is possible to study the intra- and extraneuronal components of monoamine deamination in brain. In both man and rat, the ratios of activities of MAO-A/MAO-B are higher intra- than extraneuronally. As a result of this difference in cellular localisation in the brain, loss of neurones produces a change in the ratios of activities of MAO-A/MAO-B. It is also possible selectively to inhibit the activity of MAO-A within a given neurone population. The α-methyl substituted monoamine amiflamine has been shown to inihibit MAO-A within serotoninergic neurones at lower doses than are required for inhibition in other neurones. The usefulness of this compound in the elucidation of the functions of intra- and extraneuronal MAO are discussed.
Reactivity of Small Vessels from Mature to Senescent Female Rabbits
Authors: Owen Thomas Lon
Published: September 2008

In order to determine if there are differences in reactivity of small arteries of cutaneous and skeletal muscle vascular beds taken from rabbits of different ages, vascular smooth muscle strips were tested in vitro with a variety of drugs. Arteries from the ear and hind limb skeletal muscle were removed from adult female rabbits, aged 6–48 months. Developed force of the vessel strips was measured during exposure to cumulative concentrations of norepinephrine, norepinephrine following propranolol, angiotensin II (skeletal muscle artery only) and histamine (ear artery only). Comparable segments of arteries from rabbits of different ages showed no significant differences in size or in maximum developed force attributable to age. A lack of beta-adrenoceptor activity was indicated in the ear arteries of all adult age groups studied, while propranolol enhanced contractile responses to norepinephrine in skeletal muscle arteries independent of age. Likewise, there were no consistent, age-related changes in the reactivity of either vessel type to norepinephrine, histamine, or angiotensin. This study indicates that small cutaneous and skeletal muscle arteries from mature female rabbits do not undergo any appreciable change in adrenergic and nonadrenergic sensitivity with age.
Release of Endogenous ATP from Rat Caudal Artery
Authors: Westfall David P. , Sedaa Khaled , Bjur Richard A.
Published: September 2008

Electrical field stimulation of the rat caudal artery (0.5-ms pulses at 8 Hz for 3 min) results in the release of norepinephrine (quantified by HPLC-electrochemical detection) and adenyl purines including ATP, ADP and AMP (quantified by HPLC-fluorescence detection). The amount of ATP released from the tissue exceeded the amount of norepinephrine. Because postjunctional α1-adrenoceptor stimulation with methoxamine also causes release of ATP, both neuronal and extraneuronal sites may contribute to the overflow of ATP. Results with the α1-adrenoceptor antagonist prazosin lend support to this notion. Prazosin (10–6M) completely blocked the release of ATP by methoxamine but only partially reduced the release of ATP by field stimulation.
One-Year Costs in Patients With a History of or at Risk for Atherothrombosis in the United States
Authors: Mahoney Elizabeth M. , Wang Kaijun , Cohen David J. , Hirsch Alan T. , Alberts Mark J. , Eagle Kim , Mosse Frederique , Jackson Joseph D. , Steg P. Gabriel , Bhatt Deepak L.
Published: September 2008

Background—

Atherothrombosis is the underlying cause of cardiovascular, cerebrovascular, and peripheral arterial disease and is the leading cause of death in the industrialized world. The objectives of the present study are (1) to examine the annual costs associated with vascular events and interventions that require hospitalization, as well as long-term medication use for the management of associated risk factors, in a US population of outpatients with multiple atherothrombotic risk factors or a history of symptomatic disease and (2) to compare costs across patient subgroups defined according to specific arterial bed(s) affected and the number of affected arterial beds.

Methods and Results—

The international REduction of Atherothrombosis for Continued Health (REACH) Registry enrolled outpatients ≥45 years of age who had established coronary artery, cerebrovascular, or peripheral artery disease or ≥3 atherothrombotic risk factors. Data on risk factors, associated medications, and vascular hospitalizations and interventions were collected. Of the total 68 236-patient REACH cohort, 25 763 were enrolled from US sites. Complete 1-year data were available for 23 974 (93%) of the US patients. Annualized medication costs ranged from $2401 to $3481. Mean annual hospitalization costs per patient were $1344, $2864, $4824, and $8155 for patients with 0 (n=6145), 1 (n=14 353), 2 (n=3106), and 3 (n=370) affected arterial beds at baseline (
P
<0.0001 for trend). Among patients with 1 affected arterial bed, mean hospitalization costs were $2999, $2010, and $3911 for patients with coronary artery disease (n=11 063), cerebrovascular disease (n=2613), and peripheral arterial disease (n=677), respectively. Annualized medication costs ranged from $2401 to $3481.

Conclusions—

These results reveal the high economic burden of atherothrombosis-related clinical events and procedures and the especially high economic burden associated with polyvascular disease.
Converting the Informed Consent From a Perfunctory Process to an Evidence-Based Foundation for Patient Decision Making
Authors: Arnold Suzanne V. , Decker Carole , Ahmad Homaa , Olabiyi Olawale , Mundluru Surya , Reid Kimberly J. , Soto Gabriel E. , Gansert Sarah , Spertus John A.
Published: September 2008

Background—

Standard consent forms result in highly variable communication between patients and physicians. To enhance the consent process and facilitate shared decision making, we developed a World Wide Web–based program, PREDICT (Patient Refined Expectations for Deciding Invasive Cardiac Treatments), to systematically embed patient-specific estimates of death, bleeding, and restenosis into individualized percutaneous coronary intervention informed consent documents. We then compared patients’ experiences with informed consent before and after implementation of PREDICT.

Methods and Results—

Between August 2006 and May 2007, patients undergoing nonemergent cardiac catheterization who received the original consent form (n=142) were interviewed and compared with those who received the PREDICT consent form (n=193). Hierarchical modified Poisson regression models were used to adjust for clustering of patients within physicians. Compared with the original consent group, those in the PREDICT group reported higher rates of reading the consent form (72% versus 44%, relative risk [RR] 1.64, 95% confidence interval [CI] 1.24 to 2.16), increased perception of shared decision making (67% versus 45%, RR 1.48, 95% CI 0.99 to 2.22), and decreased anxiety (35% versus 55%, RR 0.70, 95% CI 0.53 to 0.91). Although there were no differences between groups in patients’ ability to name complications of percutaneous coronary intervention, among patients who identified either death or bleeding as a potential complication, more patients in the PREDICT group recalled being informed of their estimated risk of that complication (death: 85% versus 62%, RR 1.37, 95% CI 1.03 to 1.82; bleeding: 92% versus 71%, RR 1.28, 95% CI 1.06 to 1.56).

Conclusions—

In this preliminary, single-center experience, individualized consent forms with patient-specific risks were associated with improved participation in the consent process, reduced anxiety, and better risk recall. PREDICT is one potential strategy for improving the current practice of obtaining informed consent for percutaneous coronary intervention.
Hypertension Subtype and Risk of Cardiovascular Disease in Chinese Adults
Authors: Kelly Tanika N. , Gu Dongfeng , Chen Jing , Huang Jian-feng , Chen Ji-chun , Duan Xiufang , Wu Xigui , Yau C. Lillian , Whelton Paul K. , He Jiang
Published: September 2008

Background—

We examined the relationship between hypertension subtype and cardiovascular disease incidence and mortality in Chinese adults.

Methods and Results—

We conducted a prospective cohort study in a nationally representative sample of 169 871 Chinese men and women aged ≥40 years. Data on systolic (SBP) and diastolic blood pressure (DBP) and other variables were obtained at a baseline examination in 1991 with the use of standard protocols. Follow-up evaluation was conducted in 1999–2000, with a response rate of 93.4%. Hypertension subtypes were defined as combined systolic and diastolic hypertension (SBP ≥140 and DBP ≥90 mm Hg), isolated systolic hypertension (SBP ≥140 and DBP <90 mm Hg), isolated diastolic hypertension (SBP <140 and DBP ≥90 mm Hg), and 2 categories of treated hypertension (SBP <140 and DBP <90 mm Hg or SBP ≥140 and/or DBP ≥90 mm Hg). After participants with missing BP values were excluded, 169 577 adults were included in the analyses. Compared with normotensives, relative risks (95% CIs) of cardiovascular disease incidence and mortality were 2.73 (2.60 to 2.86) and 2.53 (2.39 to 2.68) for combined systolic and diastolic hypertension, 1.78 (1.69 to 1.87) and 1.68 (1.58 to 1.78) for isolated systolic hypertension, 1.59 (1.43 to 1.76) and 1.45 (1.27 to 1.65) for isolated diastolic hypertension, 2.01 (1.64 to 2.48) and 1.61 (1.28 to 2.03) for treated hypertension with SBP <140 and DBP <90 mm Hg, and 3.37 (3.07 to 3.69) and 2.88 (2.60 to 3.19) for treated hypertension with SBP ≥140 and/or DBP ≥90 mm Hg, respectively, after adjustment for important covariables.

Conclusions—

Our results indicate that all hypertension subtypes are associated with significantly increased risk of cardiovascular disease in Chinese adults. Primary prevention of hypertension should be a public health priority in the Chinese population.
Clinical Outcome After Surgical Correction of Mitral Regurgitation Due to Papillary Muscle Rupture
Authors: Russo Antonio , Suri Rakesh M. , Grigioni Francesco , Roger Véronique L. , Oh Jae K. , Mahoney Douglas W. , Schaff Hartzell V. , Enriquez-Sarano Maurice
Published: September 2008

Background—

Papillary muscle rupture (PMR) is an infrequent but catastrophic complication of acute myocardial infarction (MI). Although always considered, surgical treatment is often denied because of high operative mortality. Moreover, the effects of surgery for PMR on long-term outcome, particularly compared with expected outcome after MI, are undefined.

Methods and Results—

Fifty-four consecutive patients (age, 70±8 years; 74% male) underwent mitral surgery for post-MI PMR from January 1980 through December 2000. Severe presentation (cardiogenic shock, pulmonary edema, or cardiac arrest) was noted in 91% preoperatively. Performance of coronary artery bypass graft was associated with lower operative mortality (odds ratio, 0.18; 95% CI, 0.04 to 0.83;
P
=0.011), whereas there was a trend for lower mortality after surgery after 1990 (odds ratio, 0.28; 95% CI, 0.06 to 1.3). Thus, operative mortality (overall, 18.5%) decreased from 67% up to 1990 without coronary artery bypass graft to 8.7% after 1990 with coronary artery bypass graft. Overall 5-year survival was 65±7%, and survival free of congestive heart failure was 52±7%. Five-year survival of 30-day operative survivors was 79±4%, identical (
P
=0.24) to that of matched controls with MI (similar age, sex, ejection fraction, MI location, and MI year). Survival free of congestive heart failure was similar in PMR cases and MI controls (10-year survival, 28±8% versus 36±6%;
P
=0.46).

Conclusions—

Surgery for post-MI PMR involves a notable operative mortality, but there are recent trends for lower operative risk, particularly with associated coronary artery bypass graft. Long term after surgery, outcome is restored to that of similar MI without PMR. These encouraging observations emphasize the importance of prompt diagnosis and aggressive therapeutic approach for patients incurring PMR after MI.
Conditional
Dicer
Gene Deletion in the Postnatal Myocardium Provokes Spontaneous Cardiac Remodeling
Authors: da Costa Martins Paula A. , Bourajjaj Meriem , Gladka Monika , Kortland Mara , van Oort Ralph J. , Pinto Yigal M. , Molkentin Jeffery D. , De Windt Leon J.
Published: September 2008

Background—

Dicer
, an RNAse III endonuclease critical for processing of pre-microRNAs (miRNAs) into mature 22-nucleotide miRNAs, has proven a useful target to dissect the significance of miRNAs biogenesis in mammalian biology.

Methods and Results—

To circumvent the embryonic lethality associated with germline null mutations for
Dicer
, we triggered conditional
Dicer
loss through the use of a tamoxifen-inducible Cre recombinase in the postnatal murine myocardium. Targeted
Dicer
deletion in 3-week-old mice provoked premature death within 1 week accompanied by mild ventricular remodeling and dramatic atrial enlargement. In the adult myocardium, loss of
Dicer
induced rapid and dramatic biventricular enlargement, accompanied by myocyte hypertrophy, myofiber disarray, ventricular fibrosis, and strong induction of fetal gene transcripts. Comparative miRNA profiling revealed a set of miRNAs that imply causality between miRNA depletion and spontaneous cardiac remodeling.

Conclusions—

Overall, these results indicate that modifications in miRNA biogenesis affect both juvenile and adult myocardial morphology and function.
Incidence and Risk Factors for Stroke in American Indians
Authors: Zhang Ying , Galloway James M. , Welty Thomas K. , Wiebers David O. , Whisnant Jack P. , Devereux Richard B. , Kizer Jorge R. , Howard Barbara V. , Cowan Linda D. , Yeh Jeunliang , Howard W. James , Wang Wenyu , Best Lyle , Lee Elisa T.
Published: September 2008

Background—

There are few published data on the incidence of fatal and nonfatal stroke in American Indians. The aims of this observational study were to determine the incidence of stroke and to elucidate stroke risk factors among American Indians.

Methods and Results—

This report is based on 4549 participants aged 45 to 74 years at enrollment in the Strong Heart Study, the largest longitudinal, population-based study of cardiovascular disease and its risk factors in a diverse group of American Indians. At baseline examination in 1989 to 1992, 42 participants (age- and sex-adjusted prevalence proportion 1132/100 000, adjusted to the age and sex distribution of the US adult population in 1990) had prevalent stroke. Through December 2004, 306 (6.8%) of 4507 participants without prior stroke suffered a first stroke at a mean age of 66.5 years. The age- and sex-adjusted incidence was 679/100 000 person-years. Nonhemorrhagic cerebral infarction occurred in 86% of participants with incident strokes; 14% had hemorrhagic stroke. The overall age-adjusted 30-day case-fatality rate from first stroke was 18%, with a 1-year case-fatality rate of 32%. Age, diastolic blood pressure, fasting glucose, hemoglobin A
1c,
smoking, albuminuria, hypertension, prehypertension, and diabetes mellitus were risk factors for incident stroke.

Conclusions—

Compared with US white and black populations, American Indians have a higher incidence of stroke. The case-fatality rate for first stroke is also higher in American Indians than in the US white or black population in the same age range. Our findings suggest that blood pressure and glucose control and smoking avoidance may be important avenues for stroke prevention in this population.